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EK-BA11A-TM-002

December 1981

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Document:	BA11-A Mounting Box and Power System Technical Manual
Order Number:	EK-BA11A-TM
Revision:	002
Pages:	98
Original Filename:

OCR Text

EK-BA11A-TM-002

BA11-A Mounting Box and Power System
Technical Manual

digital equipment corporation - maynard, massachusetts

1st Edition, December 1979
2nd Edition, March 1981

The material in this manual is for informational purposes and is
subject to change without notice.
Digital Equipment Corporation assumes no responsibility for any
errors which may appear in this manual.

Printed in U.S.A.

The following are trademarks of Digital Equipment Corporation,
Maynard, Massachusetts:
DIGITAL

DECsystem-10

MASSBUS

DEC

DECSYSTEM-20

OMNIBUS

PDP

DIBOL

0S/8

DECUS

EDUSYSTEM

RSTS

UNIBUS

VAX

RSX

VMS

IAS

9/81-15

CONTENTS

GENERAL ...ttt
et sttt et e s st esrm e e e e
PHYSICAL DESCRIPTION......cooiiiiiie
ettt ettt
H7140 POWER SUPPLY ...ttt
s
H7750 BATTERY BACKUP UNIT (OPTIONAL).....ccctieiieieeieeeeeie et
RELATED DOCUMENTS ...ttt
sttt s
es

(U I~

TS I S

INTRODUCTION

CHAPTER 1
ok

Page

1-1
1-1
1-2
1-2

1-2

CHAPTER 2

INSTALLATION

2.1

2.4

UNPACKING AND INSPECTION.....cccoiiieiitieeieeeee
et eeteeieeeeeeeseene
2-1
BA11-A Mounting Box Removal...........cccciiiiiiiiiiiii
e,
2-1
BA11-A MOUNTING BOX INSTALLATION ......ooiviiiiiiieiriieereeereeeenes 2-1
Power Connections (AQC) ... ieieciiiiieceeecrrrree
s
eeeenearae e s s s neees
2-1
AC Power Control Cabling.............oooviieiiiiiiiiiiiiee
e 2-4
120 Vac to 240 Vac Power Supply Conversion.........ccccceeeeeveeeenereeiienicieeeenennn. 2-5
OPTIONAL UNIT INSTALLATION ......ooiciitieteeceeere
e eeeee e sree
2-8
872-D, -E Power Controller Installation ..........cccoouviiiuirereiiiiieiiieeeeeeeeeeeneeene 2-8
H7750 Battery Backup Unit Installation........ccccccceeeeiieiniiiinniieceecceen. 2-8
OPTIONAL BACKPLANE MODULE ASSIGNMENTS .......ccccciviiiiiirernne 2-13

CHAPTER 3

FUNCTIONAL OPERATION

2.1.1

2.2
2.2.1
2.2.2
223
2.3
2.3.1
2.3.2

H7140 POWER SUPPLY FUNCTIONS ...ttt 3-1
Signals and VOoItages.......ccoceeeiiiiiiieiciiiiine ettt e et
3-1
Internal Signals and Voltages........ccccceeviieiecerinennnnen. eerereeerrreeanaraaans 3-1
External Voltages and Signals..........cccoeovviiiieiiiiiinieccie
e 3-2
POWER SUPPLY OPERATIONS.. ...ttt ettt 3-3
INput ASSEMDBLY ....coiiiiiiiiiiiie
et
3-8
Bias and Interface CirCuitS......cccoeiioiiiieiiiiiieiieeeeetee e 3-8
Bias VOltage. ...coooiiiiiiieeeeee ettt e
ee s
3-8
DC Voltage MONItOTING.......ccoievitirerieierierereeeeeeeeiteniteeeee
eeeseeees 3-8
INOIMAl OPETALION .....eeereeiieeiierieeeeeeeeceeeitteeesreeeesseeeessnaneeesssennsaraesnns
3-8
Standby Operation .........cccceiiiiir it 3-12
TeMPErature SENSINE....ccocuviiriirrieetieeirreieereterreesreteeesteeessenneeeessanreesesnss 3-12
Line Time Clock (LTC) Signal .......ccocooiiiieeiieeieeevieeeeeeee
e 3-12
MemOTy VOIAZE ..ocoeineeereiiieeeeeeee
ettt e e
ee e s e 3-12
35 VAC ittt
ettt s 3-12
Memory Voltage Regulators...........coooveeiiiiiiiiineieceteee
eaeeen 3-15
45 B Regulator CirCuit .....ccoeeeiioeeniiee e
e e e e e 3-15
412 B Regulator CirCUit ......ceeieeceeeiieieieeciieeeeee
e e eecree e e e e 3-15
— 12 B Regulator CirCUit ......ceoeceeiiiiiieciccieie
et eeretreeeeee e s e 3-18

iii

CONTENTS (Cont)
Page
3.2.5

Logic Voltage Generation.........c..oueeiieueriieeeeieeeecceeee

et 3-18

3.2.5.1

45V at 120 A LogIiC POWET......coiiiiiiieiieeeee e 3-21

3.2.5.2

— 15 VLOZIC POWET .....oooiiiiieii

3.25.3

F ISV POWET .. 3-23

3.2.6

e 3-21

Fan Voltage Generation..........cccceeeeeeieiriieiiiiiicecee
e
e 3-23

3.3

872-D, -E POWER CONTROLLER FUNCTIONS .....ccooiiiiiieeeeeeeeeeee 3-23

3.4

H7750 BATTERY BACKUP FUNCTIONS .......coooiie
e 3-23
Signals and Voltages.............. ett
ettt e r e et et e e e et tr e eennbee e erabaseaeeesanes 3-27

3.4.1

Battery Backup Operation.........ccooecieereeiiiieiinicieeiee

e 3-27

SERVICE
POWER CHECKS ...ttt
e
AC Power DiStribution ........cococciivieiiiieieiie
et

4-1
4-1

Initial AC Power CheCKS....ccccoevuiiiiirieciieceeeeieeeeeee
e
DC Power Distribution .........cccccevevieriieiieeiceiiccceeeeee
e
e

4-1
4-2

e
W R =

O RO
—_

CHAPTER 4
:[; e
ket ks
N [N N T NS T N I S e e e

34.2

4.2.2.1
4.2.2.2

4.2.2.3
4.2.3

4.2.4
4.24.1
4.2.4.2
4.2.5

4.2.5.1
4.2.5.2
4.3

4.3.1

4.3.2
4.3.2.1

4.3.2.2
4.3.3

4.3.3.1

4.3.3.2
4.3.4
4.3.4.1

4.3.4.2
4.3.5
4.3.6

Initial DC Power ChecksS.......ccoviveriiiiiiieeeeeeeee
e
REMOVAL AND REPLACEMENT PROCEDURES.............. e et e

4-2
4-2
BA11-A Mounting Box in PDP-11/X44 or Similar Cabinet.......................... 4-2
Mounting Box Removal...........cccooiieeiiiiiiiiccce
e 4-2
Interface Bracket Removal/Installation..........ccccoooiiiniiniiiieninnen, 4-11
Mounting Box Replacement.............ccccoeioiiiiiiiiniiiniece e 4-1%
BA11-A Mounting Box on SHdes.......ccccooeeeiiiiiiiiieeeeeeee e 4-13
BA11-A Slide Mounting Unit Removal ............cccoviivviiiiiiiiiieiecie, 4-13
Index Plate Installation .........ccccoevieeiiiiiiiciieiccee
e 4-17
BA11-A Slide Mounting Unit, Replacement ............cccccoovvvvnvieeeeiennenn.. 4-18
Fan Assembly Removal and Replacement ...........ccccoeeeuiiiieciiiieenninececc, 4-18
H7140 Power Supply Unit......cccoeiiiiiiiiiiiiieeeeeeeeee e 4-20
Power Supply Unit Removal .......c.cccccovviiiiiiiiiiicieceeeeeeee 4-20
Power Supply Unit Replacement ............ccccoeeeieiieiiiiiiiiiiiieceiee
e 4-24
CPU Backplane Assembly.......cccouviiiieiiiiiiiiiiecceceeee
e, 4-25
Backplane Assembly Removal ..........ccccovviviiieiiiiiiiiccec
e, 4-25
Backplane Assembly Replacement ............coceovviimecieiiciiieiiiciieeeeeee 4-26
POWER SUPPLY UNIT, COMPONENT LOCATIONS........cooviiieeeeecee, 4-29
INPUL ASSEMIDLY ..cooniiiiiiiiiie
e
e e 4-29
Bias and Interface Components............cccovvvieeiiiieeeiiiieeceeececeee 4-29
Bias and Interface Module.........ccccooeriiiiiiiiiieeeeceeee
e 4-30
Mother Module..........coccoiiiiiiiiiiece
e 4-30
Memory Voltage ASSEmDbIY ........ooevviiiiiiiiiiiiiececeee
e 4-30
Memory Inverter Module..........c.oovviiieiiiiiiiiiicee e 4-30
Memory Regulator Module........cccocveiiiiiniiiiieeeeeceeeee
e, 4-30
Logic Voltage AsSembly ........cccooeoiiiiiiiiiiiiice
e 4-31
Logic Inverter Control Module ............coooeiiiiiiie, 4-31
Logic Inverter Module ..........ccoveeiiiiiiiieee
e 4-31
Output ASSEMDBLY ...cooiiiiiiiiiiiiieee
e e 4-31
Power Distribution Module ............cooveioiiiiiiiiiiiiee
e 4-31

FIGURES
Figure No.

Title

Ahhhhhwwtpwwwuwuuuwu
RV
A YL LU
SO SR I NS
RN\

BATT-A DIMENSIONS. ....ceittiiiieieiiiiiieieetee
it e ee et aeiiieeeeaateeeteteeaereessbnsetaeeaeseesessssnens
Mounting Box in HI961 Cabinet.........ccceoviiieeiiiiiiiieeeeee
e

4-7
4-8
4-9
4-10
4-11

4-12
4-13

4-14
4-15

4-16
4-17

4-18
4-19
4-20

4-21

Page
1-1
1-2

Mounting Box in System Cabinet ..........cc.ccooeeeiiiiiiiiiiiiieie
e
1-3
BAI11-A Mounting Box Packaging.........cceeeeiiiiieiiieciiiieiieecee
e 2-2
Mounting Box, Rear Panel Components............cocccveriiciiienieiiiie e, 2-3
BA11-AA, AB AC Connector Specifications ............ccccveeeieeeivirieeeeiiiieeeecieee
e 2-4
872-D, -E Power Controller Unit AC Connector Specifications............................. 2-5
Typical Power Control Cabling..........coccueveeiieiiiiiiieiiieeieeee e 2-6
H7140 Unit, AC Power Cord Assembly Removal............ccccoviiiiiiiiniiiiiene, 2-7
872-D, -E Power Controller Front Panel Locations .............oooovviiimineeiiceeeeeeeeeenn 2-9
H7750 Unit, Cable CONNECHIONS .....coiiiiiiiiiieieeee
et
ee et e e eteeeae e e e eenanenes 2-10
H7140 Unit, 4300 VdAC TesSt LOCAtION ....uvueeeeiieeeeeeeeeeeeee et 2-11
Optional Backplane Connector ASSigNMments............ccceeeiieiieieeeiieerinieeieeeeeeeeervenns 2-13
Power Supply, External Signals and Voltages .........cccooovvviiiiiiiiiiiiiicceececeeen, 3-2
H7140-AA, -AB Power Supply Interconnection............ccuevveveieiieeeciiiieeeeee
e, 3-4
Power Supply Functional Block Diagram............ccccccoiiiiiiiiiiiiiin
e 3-7
Bias and Interface Circuits, Block Diagram..........cccoviviiiiiiiiiiiieec, 3-9
Memory Voltage Generation Functional Block Diagram ..........ccccocovveeivnieeenne... 3-13

+ 5 B Voltage Regulator, Circuit Block Diagram..............cccocvveriiiiieiicciiieeene, 3-16
+ 12 B Voltage Regulator, Block Diagram............ccocovviiiiiiiiiiiiiiiiiie e, 3-17
— 12 B Regulator, Block Diagrami.........ccccccueiiiirieeeieeeeiieieeeeee
e 3-19

Logic Module Voltage Generation, Functional Diagram ............cccceoeeeiiiiierernnnnnn. 3-21
— 15 V Power, Functional Diagram.........cccocoeoiiiiiiiiiiiieiieeiieeecn
e 3-22
+15 V Power, Functional Diagram ..............ccoooiiiiiiiiiiiiiiiiiceeec
e 3-24
Fan Voltage Generation, Functional Diagram............cccocoivviiiiiiiiiiiciiiniinieeeineeeen. 3-25
872-D, -E Unit, Simplified Diagram..........cccccoviiiiiiiiriiiiiieiieeiecnieree
e eeiiineeeee 3-25
H7750 Unit, Simplified Diagram ........ccocccoeiiiiiiiiiiiiiiie
et 3-26
Backplane Assembly, Pin Designations .........ccccccierriereiieeiieneeier
e, 4-3
Cabinet Type IdentifiCation......c.ccceiieriiiiiiiiiiiiiieecce
e 4-4
Mounting Box Release Lever, System Cabinet ..........cccccoeeeiiiiiiiiiiiiiee
e, 4-5
Top Cover Mounting (TYPE A) .eeeeeeeeiieeeiie et e e et eeae e 4-5
Top Cover Mounting (TYPe B)...oooeeeeeiieieee
et 4-6
BA11-A Unit Cable Clamps .......coceuveeeeiiieeeiree
et et 4-7
BA11-A Type B Box Slide Latch Locations .......ccccceevcviieeinieiiciniiiieieer
e 4-8
System Cabinet Safety Lever . ..ot 4-9
System Cabinet, Mounting Box Hardware .............cccoooeiiiiiiiiiiiiiiie
e, 4-10
Interface Bracket MOUNUING ......coooieiiiiiiiieecie
et
ee e e aee 4-11
Mounting Box Release Lever Slide Mounted Unit.........cccoeevieiiiiiriiiiciiiiiinienee, 4-14
Slide HOIA LeVETS......ouuiiiiiiiieiee
ettt e e e ee e rre e e e e e senbneae s 4-15
Slide to Index Plate MoOunting ..........ccooiiiiiiiiiiiiiciieie
e e e 4-16
Index Plate MOUNTING .......oooiiiiiiiiiiiiiiiee et
eeee s e e ee e s e eseenee 4-17
Fan Assembly Removal .........ooooiiiiiiiiiiiiii
e 4-19
Power Supply Unit, Rear Mounting SCrews .........ccccoevuieeiriiieeerinieeeee
e eeereeenn 4-21
Power Supply Unit Removal.........coccoiiiiiiiiee
e 4-21
Mounting Box, Power Cable Connections.............ccccvvveiiieeeeeeeeeeceecceeeveeeeee 4-22
Power Distribution Panel Connectors and Cable Assembly .........ccceeeviviiiinnieeennn. 4-23
CPU Backplane Assembly MoOUNting .......ccccceeiviiriiiciinicieiiiniiiee e 4-27
Backplane Assembly AIIgNment ...........ccooiiiiiiiir
et
e e 4-28

FIGURES (Cont)
Figure No.
4-22
4-23

4-24
4-25

4-26
4-27

4-28

4-29
4-30

4-31
4-32
4-33
4-34

4-35
4-36

4-37
4-38
4-39
4-40

Title

Page

H7140 Unit Module and Assembly Locations..........cccceecvveereieeercieeeciieecreecreeee, 4-29
Input Assembly, Component LoCations..........ccccevveeerreiereccieeiieeieeeeeee
e, 4-30
Bias and Interface Module, Interface and Control Components............ccceeeuvn...... 4-31
Bias and Interface Module, Bias Voltage Components.............cccceeeuieeciieceecreennne. 4-33

Bias and Interface Module, Fan Voltage Components ............ccccceveveeeiveecnrreeennene. 4-33
Mother Module COMPONENLES ........ouiiieriiiiiieiiiiieeiie
e eeeere e reeerre e e evae e eaee e 4-34
Memory Voltage Assembly Components..........ccceevevueniiereeiiireciiieeeereeeeeree
e 4-34
Memory Inverter Module Components............cceeveeerieuieeeniieennieesenieeeneesrieeesiee
e, 4-35
Memory Regulator Module, +5 B Components ............cccceeeeeeeecieeeieeccreecneeenee 4-35
Memory Regulator Module, + 12 B Component Locations ..........cccceeeceveeeeiannnenene. 4-37
Memory Regulator Module, —12 B Components .........cccccceevevereeerccveeecnneeeennnnee. 4-37
Logic Inverter Assembly COMPONENtS.........coovvumiuiiiiiiiiiiieeiiiieeeee
e, 4-38
Logic Inverter Control Module, Voltage Reference and
Sensing COMPONENLS.........ceiireieiriiieiiiientieienieeeeereteeesereeeereesnreeessressreserensess 4-39
Logic Inverter Control Module, —15 V ana 415 V Components ......................... 4-40
Logic Inverter Module Components ...........coceeveeveeeeiiiiiereciiieeeeeiiece e 4-41
Output Assembly COMPONENLS ........ceereiiiiriiiiiireecieee
e 4-42
Snubber Module COMPONENLS........ccceeuveiiiiiiiiieiie
e
ee
e e eeree e e e 4-42
Power Distribution Module Components............cceeeeeeeivieeeeiieeeeeeieie
e eeeveee e 4-43
Power Distribution Cable Assembly WIring............ooeeeveiiiiiiiiieiccciiieeee
e 4-43

TABLES

—

)

et e

Awwlfat\)»-w—u—

Table No.

Title

Page

H7140-AA, -AB Power Supply Specifications ..........ccccccevevviieereciieeencieeecieveee,
H7140 Output Specifications ............. eeeeeeteteerretteeeearabeeeiaraeeeanretaeeanrreeearresennnrees

1-4
1-6

Related PubliCations ............cccceieiriiiiiiciccie ettt
Input Power Cable ASSembIY........coooiiiiiiiiiiiii
e
e
Control Panel Signals.........cooooviiiiiiiiiiii
e
Backplane Signals .........cooovoiiiiiiiiiiii
e
Power Controller Signals.........coceeiviiiiiieeeiiii
e
CPU Backplane Connector P1, Signals and Voltages..........ccccceeeeeeeeiiiirieeennneennn.

1-7
2-5
3-1
3-3
3-3
4-3

CHAPTER 1
INTRODUCTION

1.1

GENERAL

This manual describes the BA11-A mounting box, its power system and the optional battery backup
unit. The BA11-A is used to house the PDP-11/44 and other PDP-11 processors.
1.2 PHYSICAL DESCRIPTION
The BA11-A mounting box is shown in (Figure 1-1). It contains the H7140 power supply, the specified

systems backplane (the PDP-11/44 backplane), and three cooling fans for the mounting space and power supply. The BA11-A also has space for mounting optional backplanes such as the DD11-CK and
DD11-DK. The BA11-A may be mounted in a slide mount installation (Figure 1-2) or a cabinet system
(Figure 1-3).

66.01 CM

(25.99 IN)

26.34 CM
(10.37 IN)

46.99 CM

(18.5 IN)

TK-3479

Figure 1-1

BAI11-A Dimensions

1-1

l
\

eoefieeeooeoeeboiooeeoeoaeoeooooeeoooeo

&
S5
58
00
60
56
O
6
O
0D

UED

LTHTTTEETETRII
T
|l|lllIlI|III|IIII
IIIlIII
UL

NOTE:

SLIDE AND SLIDE INDEX PLATE
ARE USED WITH RACK MOUNTED VERSION.
TK-4183

Figure 1-2

1.3

Mounting Box in H961 Cabinet

H7140 POWER SUPPLY

The H7140 power supply is used in the BA11-A. Table 1-1 lists the H7140 input specifications. Table
1-2 lists the H7140 output specifications.

1.4 H7750 BATTERY BACKUP UNIT (OPTIONAL)
The H7750 battery backup unit provides dc refresh power to MOS memory and keeps the cooling fans
operating in the event of an ac power failure.

The unit contains three sealed, 12 Vdc, lead acid batteries that supply 36 Vdc to the memory regulators
in the H7140 and the cooling fans.

1.5

RELATED DOCUMENTS

Table 1-3 lists manuals and publications that contain information related to the installation and operation of the BA11-A mounting box.

WU, .,

Wi,
L[
WU, .,
W,

TK-3631

Figure 1-3

Mounting Box in System Cabinet

1-3

Table 1-1

Characteristics

H7140-AA, -AB Power Supply Specifications

Description

H7140-AA Power Supply
Line voltage

90 Vrms — 128 Vrms, single phase, two wire and ground (120 Vrms nomi-

nal)
Frequency

Current (ac)

47-63 Hz

15 A rms max. at 120 Vac

55 A peak max. at 120 Vac
Power factor
Inrush current

Greater than 0.60 at full output load and low input voltage (90 V)
65 A peak at 128 Vrms for one-half cycle, followed by repetitive peaks of
decreasing amplitude for an additional 8 cycles of the input voltage

Power

1350 W with maximum load applied at nominal voltage output

Overvoltage
condition

Can withstand input overvoltage of 150 Vrms for one second

Noise transient
(Maximum acceptable)
Low energy

transients

300 V peak voltage spike* containing not more than 0.2 watt-seconds of
energy per spike

High energy

transients

1 KV peak voltage spike* containing not more than 2.5 watt-seconds of
energy per spike

Conducted noise

CW-10 KHz to 30 MHz, 3 Vrms

Radiated noise

RF field strength — 10 KHz to 30 MHz, 1 V/M 30 MHz to 1 GHz: 10
V/M

H7140-AB Power Supply

Line voltage

180 Vrms — 256 Vrms, single phase, two wire and ground (240 Vrms nominal)

Frequency

47-63 Hz

Table 1-1

Characteristics

H7140-AA, -AB Power Supply Specifications (Cont)

Description

Current (ac)

9.0 A rms max. at 240 Vac
33 A peak max. at 240 Vac

Power factor

Greater than 0.60 at full output load and low input voltage (180 V)

Inrush current

130 A peak at 256 Vrms for one-half cycle, followed by repetitive peaks
of decreasing amplitude for an additional 8 cycles of the input voltage

Power

1350 W with maximum load applied at nominal voltage output

Overvoltage

condition

Input overvoltage of 300 Vrms for one second (maximum)

Noise transient

(Maximum acceptable)
Low energy
transients

300 V (peak voltage spike* containing a maximum of 0.2 watt-seconds of
energy per spike)

High energy
transients .

1 KV (peak voltage spike* containing a maximum of 2.5 watt-seconds of
energy per spike)

Conducted noise

CW-10 KHz to 300 MHz, 3 Vrms

Radiated noise

RF field strength — 10 KHz to 30
MHz, 1 V/M 30 MHz to 1 GHz: 10 V/M

* A spike is a voltage transient of either polarity and of either common or differential mode, with a rise time (10% to 90%) of
0.1 us or less, and a fall time (to 10%) of 10 us or more. The average power of spikes should not exceed 0.5 W.

1-5

Table 1-2

H7140 Output Specifications

Nominal Qutput Voltages

Logic Voltages

Parameter

Memory Voltages

+5.1V

+15.0V

-15.0V

+12.0V

-12.0V

+5.1V

Maximum

6.0 A
120.0 A

0.0 A
3.0A

0.0A
30A

0.0A
5.0A

0.0 A
1.0 A

0.0A
10.0 A

Static Load/Line

+0.10V

+0.30 V

0.30 V

+0.24 V

+0.10 V

Ripple Voltage
Noise Voltage

100 MV, P-P

£300 MV,P-P

#300 MV,P-P

51 MV, P-P

240 MV,P-P

150 MV,P-P

240 MV,P-P

150 MV,P-P

100 MV, P-P

Dynamic Regulation

£120MV,P-P

t18 A

£120MV,P-P

0.5 A

£51 MV, P-P

Over/Undershoot

0.5 A

100 MV

1.0 A

300 MV

2.0 A

Current Limit

300 MV

$0.25 A

125 to 140 A

240 MV

3.2t04.0 A

240 MV

3.2t04.0 A

100 MV

5.5t06.5 A

1.8t03.0 A

10.5to 13.5 A

+6.5V

180V

18.0V

+15.0V

-15.0V

+6.5V

+7.0V

+21.0V

+16.0V

-16.0V

+7.0V

Output Current
Minimum

Regulation

Initiation Point

Overvoltage Limit
Maximum Trip Point

Maximum Voltage

Table 1-3

Related Publications

Title

Document Number

PDP-11/44 System Technical Manual

EK-KD11Z-TM

PDP-11 Peripherals Handbook

EB-07667-20/78

PDP-11 Processor Handbook

EB-17716-18/79

BA11-A Box Assembly Field
Maintenance Print Set

MP-00832

11/44 System Field Maintenance
Print Set

MP-00809

872 Power Controller Field
Maintenance Print Set

MP-00865

BA11-A Unit Assembly (IPB*)

EK-BA11A-IP

H7140 Power Supply (IPB¥)

EK-H7140-1P

*[1lustrated Parts Breakdown

1-7

CHAPTER 2
INSTALLATION

2.1

UNPACKING AND INSPECTION

The BA11-A mounting box is packaged and shipped in reinforced cartons and protected internally by
foam inserts and a polyethelene bag. Before unpacking any carton, remove the packing list from the
container.
NOTE

Retain the packing material and shipping containers
in the event reshipping is required.

2.1.1

BA11-A Mounting Box Removal

The BA11-A mounting box is packaged in reinforced cartons and protected by foam inserts and a
polyethelene bag as shown in Figure 2-1. To remove the unit from the container, perform the following
procedure.
CAUTION

The BA11-A unit weighs approximately 34 kg (75
Ibs). Use care when lifting the unit from the carton.

NNk
w =

Open the leaves of the outer carton by cutting the tapes at the seams.
Remove the inner carton from the foam protector.

2.2

Open the leaves of the inner carton by cutting the tape at the seams.
Remove the side and rear protectors.
Remove the unit from the polyethelene bag.

Remove the bezel protector.
Inspect the unit for visible damage and ensure that the contents are complete.

BA11-A MOUNTING BOX INSTALLATION

The BA11-A mounting box may be installed in a system cabinet like the one used in the PDP-11X44,
or the mounting box may be mounted on slides in a 48.26 cm (19 in) cabinet. For instructions on the
installation of the BA11-A mounting box refer to Paragraph 4.2 of this manual.

2.2.1

Power Connections (AC)

The BA11-AA, -AB mounting boxes are supplied with a 2.74 m (9 ft) line cord attached to the rear of
the unit. Figure 2-2 shows the ac line cord, circuit breaker, and connectors. The line cord plug may be
connected to an 872-D, -E power controller unit (or equivalent) or directly to the ac power receptacle at
the site.

2-1

SIDE PROTECTOR

REAR PROTECTOR

45
BA11-A UNIT

\POLY BAG

BEZEL PROTECTOR

FOAM PROTECTOR

TK-3529

Figure 2-1

BAI11-A Mounting Box Packaging

2-2

[

- =

AT I

~7r
o~

| B

O 0

eIkl

FUEUES R UGN

§ R

A [ | '
r T
I |N
EnEn i
il

]

QIF
o=

AC POWER /

==
©
©

@®

/o ©

120/240

SWITCH

TERMINAL COVER

]

VAC

CIRCUIT
BREAKER

i8lto

LINE CORD

TK-4389

Figure 2-2

Mounting Box, Rear Panel Components

2-3

The 872-D, -E power controller, used in systems such as the PDP-11X44, allows the key switch on the
control panel to apply and remove ac power from all units connected to the switched outputs of the
power controller. In addition, the power control bus, used to control the ac power internally, can be

routed externally to switch ac power from any other power control unit.

Figure 2-3 shows the type of connector plugs and receptacles used, and the DIGITAL part numbers
for the connectors. The color of the cable wires connected to the plug is also indicated. The NEMA 520 P plug is attached to the BA11-AA cable. The NEMA 5-20 R and 6-15 R are dual-receptacle outlets
that can be installed within a wall outlet box or a power distribution unit.

PIN SIDE

NEUTRAL

PIN SIDE

NEUTRAL

PHASE

prasg (BLUE)

(BLUE)
125V 20A

(BRN)

240V, 15A

MALE PLUG

PDP—11/44—CA

PDP—11/44—CB

NEMA *

DESIGNATION

5-20P
5-20 R
6—-15P

6-15R

POWER

(BRN)

RATING

DIGITAL PART NO.

125V 20A
T

12-15183-00
12-12265-00 * *

240V, 15A

90-—08853—00

12-11204-01 * *

* P = PLUG
R =

RECEPTACLE

DUAL RECEPTACLE OUTLET
TK-4390

Figure 2-3

BA11-AA, -AB AC Connector Specifications

The 872-D, -E power controller is supplied with a 4.57 m (15 ft) cord and plug that connects to a
receptacle at the site. Figure 2-4 shows the cord connector configurations and the DIGITAL part
numbers for the plugs and receptacles.

2.2.2

AC Power Control Cabling
Figure 2-5 shows a typical cabling configuration that enables control of the ac power from the control
panel keyswitch on the BA11-A CPU unit. The power control bus cabling also contains an overtemperature line which will remove the ac power from the units connected to the switched receptacles
of the 872-D, -E unit when the internal temperature of a unit exceeds a specified level.

2-4

RECEPTACLE (FEMALE)
PHASE

PLUG (MALE)

NEUTRAL

(NEUTRAL

X
GREEN
CARTH

_{?

PREFERRED)

GROUND

WHITE

PHASE OR

NEUTRAL

NEMA L6-20R

NEMA L6 -20P

230 V USED WITH THE 872—E

RECEPTACLE (FEMALE)

GREEN G

EARTH

PLUG (MALE)

NEUTRAL

PHASE

GROUND \0/

NEMA L5-30R

NEMA L5-30P

115 V USED WITH THE 872-D

CONNECTOR SPECIFICATIONS

MODEL

PLUG

RECEPTACLE (SUPPLIED BY CUSTOMER)

NUMBER

POWER

RATING

NEMA CODE

DEC PART NO.

872—D

115 v

30 A

L5-30P

L5-30R

12-11194

872—E

230 V

20 A

L6-20P

L6-20R

12-11191

TK-4391

Figure 2-4

872-D, -E Power Controller Unit AC Connector
Specifications

2.2.3
120 Vac to 240 Vac Power Supply Conversion
The H7140 power supply can be converted to operate with either 120 Vac input power or with 240 Vac
input power. The conversion requires the replacement of the input power cable assembly. This assem-

bly consists of the line cord, connector cover, and plastic bezel. Table 2-1 lists the DIGITAL part
number for each assembly.

Table 2-1
Part No.

Input Power Cable Assembly

Input Power

Power Supply Designation

7016478-00

120 Vac

H7140-AA

7016478-01

240 Vac

H7140-AB

PDP-i1X44 CABINET OR PDP-li/44
RACK

CABINET
BA11-AA, -AB MOUNTING BOX

POWER

CONTROL

AC POWER

|,/ CORD ASSEMBLY

;r}\m
A, %

NN 2
/A

872-D, -E POWER CONTROLLER

%
2

NONSWITCHED

POWER

——

CONTROL

TO WALL

AR,

SWITCHED

RECEPTACLE

RECEPTACLES

= Q POWER CORD

RECEPTACLES

CABLE NO.
7008288

POWER CONTROL

BUS TO OTHER
SYSTEM UNITS

H7750-AA, BATTERY BACKUP

-AB, -AC, -AD

;

POWER

CONTROL

CABLE NO.

|~ 7008288
/

N P2

A9,

J11

TK-5637

Figure 2-5

Typical Power Control Cabling

2-6

To convert the power supply from one voltage to another, perform the following procedure.

Remove the ac power cord connector of the power supply from the power controller recep-

tacle or wall receptacle.

Remove the cable clamps or fasteners used to secure the power cord to the cabinet frame.
Remove and retain the 8-32 (1) screw in the connector cover and the two 8-32 screws and
washers (2) and (3) shown on Figure 2-6.

Slide the cable assembly away from the supply so that the three 10-32 nuts that secure the
line cord leads to the filter assembly are accessible.

Remove the nuts using a 3/8 inch nut driver and remove the line cord assembly.

Change the position of the 120 V/240 V slide switch S1 to the posmon that corresponds to
the Voltage of the replacement line cord assembly. When the switchis in the up position, 120
Vacis selected, and whenin the down position, 240 Vacis selected.
Secure the replacement line cord assembly to the cabinet frame using the hardware removed
in steps 3 and 5.

NOTE
The plastic bezel holds switch S1 in the position corresponding to the voltage of the mounted line cord
assembly.

ode P
®

.l«%\fij«

BLUE

)

@ | [T

ain

/ \1 N
GRN/YEL

SLIDE SWITCH

LINE CORD
TK-3658

Figure 2-6

H7140 Unit, AC Power Cord Assembly Removal

2-7

2.3

OPTIONAL UNIT INSTALLATION

2.3.1
872-D, -E Power Controller Installation
The 872-D, -E power controller may be used with the BA11-A mounting box. To install a unit into a

standard cabinet or rack, perform the following procedures.
1.

Mount the 872-D, -E unit onto the cabinet rails using the hardware supplied with the unit.
NOTE
The power controller can be mounted at the front or

rear of the cabinet.
Connect the ac line cords from the units within the cabinet to the appropriate ac power
receptacles (switched or unswitched) on the power controller. The BA11-A CPU (PDP11/44) must be connected to an unswitched receptacle in the power controller unit.
Route the ac power cords away from the signal cables and secure the cords with cable
clamps or tie wraps.

Attach connector P1 of cable assembly (DIGITAL no. 7008288) to connector J3 or J4 located at the rear of the H7140 power supply (Figure 2-2).
Attach connector P2 of the cable assembly to connector J11 or J12 of the power controller
unit (Figure 2-7).

Set the LOCAL/OFF/REMOTE switch of the power controller unit to the REMOTE position.

Connect the ac power cord of the 872-D, -E power controller to the main power receptacle
at the site.
Set the circuit breaker of the power controller to the ON position (up).

2.3.2 H7750 Battery Backup Unit Installation
The H7750 battery backup unit may be installed in a system cabinet or in any standard 48.2 cm (19 in)
mounting rack. For example, in the PDP-11X44 system cabinet, the H7750 unit is mounted on the
vertical cabinet rails at the lower front of the cabinet. The battery backup cable assembly (DIGITAL
No. 1700177) connects from the rear of the H7750 to the H7140 power supply in the mounting box. To
connect the unit, perform the following procedures.
1.

In a PDP-11X44 system cabinet or similar installation, perform steps 1, 2, and 5 through 11
of Paragraph 4.2.1.1.

In installing the H7750 into a 48.2 cm (19 in) cabinet where the mounting box is attached to
slides, perform steps 1, 2, and 5 through 9 of Paragraph 4.2.2.1.
Mount the H7750 unit to the cabinet rails using the hardware supplied with the unit. Make
certain the toggle switch on the front panel of the H7750 unit is in the OFF position.

:O?_-—-’_\——/-/\————D
©

o e

e ®

N>
b

]

CIRCIUIT

DEZSD 0ETED @ q’
.

872-D,-E
| POWER

CONTROLLER
J1 412 e [|
&

O
sje

BREAKER

TK-5011

LOCAL/OFF/REMOTE
SWITCH
AC

INDICATOR

Figure 2-7

872-D, -E Power Controller Front Panel Locations

At the rear of the H7750 unit, attach connector P3 of the cable assembly 1700177-0) to J9
and connector P2 to J8 (Figure 2-8).

Connect the ac power cord plug of the H7750 unit to an unswitched receptacle of the power
controller.

Route the cable assembly through the rear of the cabinet and up to the rear of the mounting

box. Allow enough cable slack to prevent tension on the cable or cable connectors.
CAUTION

The H7140 power supply contains dangerous voltage
and high current capabilities. Allow five minutes after the ac power is removed from the supply to ensure
proper discharge of the power supply currents.

Remove and retain the three (8-32) screws that secure the top cover of the H7140 power
supply. These screws are located in the depressions on the top cover (Figure 2-8).

Loosen the two (8-32) screws that secure the end of the top cover to the power supply. Do
not remove the screws.

Slide the cover assembly away from the screws loosened in step 8.
10.

11.

Using a multimeter set to the 300 Vdc range, measure the voltage across pins 1 and 2 of TB1
as shown on Figure 2-9. The voltage should be less than 20 V after the 5 minute interval.
Remove the bias and interface module (Figure 2-8) by sliding the module up.

a/l
T T

TOP COVER
SCREWS
(8-32)
2 PLACES

SCREWS
{8-32}
3 PLACES

—

>‘_’

BIAS AND

INTERFACE

T
70000

MODULE

MOTHER

y
<

MODULE

\’/

H7140
POWER

¥ SUPPLY UNIT

J3
4

CABLE ASSEMBLY

NO. 1700177-0

872.D, -E
POWER

CONTROLLER
UNIT

g \\
%

47750 BATTERY

BACKUP UNIT

—

= \\\\\

CABLE ASSEMBLY
NO. 7008288

\“\
\~

5) 872-D-E POWER — §\\
CONTROLLER
UNIT
P2

s‘»

V2
—

~p3

TM~

TK-5009

Figure 2-8

H7750 Unit, Cable Connections

2-10

AY
..

‘s

TOP VIEW

REAR

+RED LEAD

TK-5010

Figure 2-9

12.

H7140 Unit, +300 Vdc Test Location

Attach connector P1 of the cable assembly to J9 on the mother module of the power supply.
The black leads of the cable assembly should be positioned toward the front of the mounting
box. The notches in the connectors will interlock when the connectors are properly positioned.
NOTE

When attaching P1 to J9, make sure all the pins of
J9 are inserted into P1. If all the pins of J9 are not
inserted into P1, the battery backup unit and power

supply will be damaged.
13.

14.

Dress the cable up and over the depression in the rear panel of the power supply.

Replace the bias and interface module that was removed in step 11. Ensure that the connector on the bottom of the module mates correctly with the pins that project upward from
the surface of the mother module.

15.

Replace the top cover of the power supply that was removed in steps 7 through 9.
NOTE
Several leads of the power suppply are routed close
to the top cover. When replacing the cover, ensure
that none of the leads will be punched or pierced
when the cover is mounted.

16.

In the PDP-11X44 or similar cabinet, perform steps 16 through 20 of Paragraph 4.2.1.3 to
replace the top cover assembly.

17.

If an overtemperature control of the output of the H7750 is desired, install the cable assembly (DIGITAL No. 7008288). Connect P1 of the cable assembly to connector J3 or J4 at the
rear of the H7140 power supply. Connect P2 of the cable assembly to connector J10 or J11
of the H7750 battery backup unit (Figure 2-8).

18.

Position the cables previously installed away from sharp objects and insure that no cable
strain exists when the mounting box is extended to its maintenance position.

19.

Secure the cables to the cabinet rails, or sections, using the existing cable clamps or other
cable fasteners.

20.

Apply ac power to the 872-D, -E power controller unit by setting the circuit breaker to the
ON (1) position (Figure 2-7).

21.

Ensure that the ac circuit breaker at the rear of the BA11-A mounting box is in the ON (1)
position.

22,

Set the toggle switch on the front of the H7750 battery backup unit to the ON (1) position.

23.

Ensure that the rotary key switch on the control panel is in the LOC, LOC DSBL or STD

BY position.
24,

Ensure that the DC ON and BATT indicators of the control panel are lighted. The BATT
indicator is on continuously if the batteries are fully charged, or the indicator flashes slowly
if the batteries are charging (less than 90 percent of full charge).

25.

Verify that the battery backup unit is functioning by performing the following steps.

Deposit a BRANCH SELF instruction (777g) at location 200g.

Load address 2003 and start the CPU.

Disconnect the BA11-A ac power cord from the receptacle. The BATT indicator light
will blink fast.
NOTE
The keyswitch should not be turned to the DC OFF
postion when performing this test. This would remove
all power from memory and destroy its contents.

Reconnect the BA11-A ac power cord to the receptacle.

2-12

Examine location 200g. Its contents should be 777g, the BRANCH SELF instruction, if
the battery backup unit is functioning properly.

2.4 OPTIONAL BACKPLANE MODULE ASSIGNMENTS
The BA11-A mounting box may contain optional backplane assemblies in addition to the basic CPU
backplane (PDP 11/44) installed in the unit.
The slot locations of the optional backplanes are divided into three categories: standard UNIBUS,
modified UNIBUS, and small peripheral control (SPC). Particular areas of the backplane are reserved
for the different types of modules as shown in Figure 2-10.
The DD11-CK and DDI11-DK are general purpose backplanes. The standard UNIBUS locations

contain all the UNIBUS connections. Rows A and B of slot 1 are the beginning of the UNIBUS in the

DDI11-CK backplanes and DD11-DK, and should be occupied by the BC11-A UNIBUS cable or a
M9202 UNIBUS connector. Sections A and B of slot 9 in the DD11-DK backplane, or of slot 4 in the
DDI11-CK backplane, are the end of the UNIBUS on the backplane. These sections should be occu-

pied by the BC11-A UNIBUS cable, M9202 UNIBUS connector, or an M9203 terminator module.
Other dedicated backplanes, such as the RH11, DH11, RK22, or RK6/711, are available as options.
The UNIBUS inputs and outputs and terminator usage are the same as described for the general
purpose backplanes, however, the module types and their locations are dedicated in these backplanes.

DD11-CK BACKPLANE

ROW

QUAD

MODULE

OR HEX
HEIGHT

QUAD
F—HEIGHT
MODULE

QUAD HEIGHT
MODULE

[ VS

QUAD OR HEX-HEIGHT
MODULES

N
W
©

SLOT NO

DD11-DK BACKPLANE

MODULE

pOW

SLOT NO.

QUAD

F—HEIGHT

J
— QUAD HEIGHT MODULE
MODULE SIDE

STANDARD UNIBUS

SLOTS

V8 4VA

MODIFIED UNIBUS

SMALL PERIPHERAL

SLOTS FOR MODIFIED

CONTROLLER (SPC) SLOTS

UNIBUS DEVICES (MUD)

Figure 2-10

Optional Backplane Connector Assignments

2-13

CHAPTER 3

FUNCTIONAL OPERATION

This chapter describes the functional operation of the H7140 power supply, the 872 power controller
unit, and the H7750 battery backup unit. Refer to the appropriate manuals listed in Table 1-2. The
field maintenance print sets, also listed in Table 1-2, contain the assembly drawing related to these units
and the ciruit schematics (CS) referenced in this chapter.
3.1

H7140 POWER SUPPLY FUNCTIONS

The H7140-AA (120 Vac) and the H7140-AB (240 Vac) units are high-frequency-switching power supplies that provide the dc voltages for the logic modules and memory modules installed in the BA11-A
mounting box. The power supply also generates the square wave voltage used to power the fans within
the fan assembly. Therefore, it is not necessary to change fans when converting from 120 Vac to 240
Vac operation.
3.1.1

Signals and Voltages

Figure 3-1 shows the signals and voltages that are transferred between the power supply and the assemblies and units within the BA11-A mounting box and between the power supply and external units. The
872-D, -E power controller unit is included with the PDP-11/X44 or similar system. The H7750 battery
backup unit is optional with the PDP-11/44 or other PDP-11 systems mounted in the BA11-A mounting
box.

3.1.1.1

Internal Signals and Voltages — Three signals are transferred between the control panel and

the power supply. Table 3-1 lists the signals and their functions.

Table 3-1

Control Panel Signals

Signal

Function

DC ON (L)

From the control panel keyswitch S1-B. Set to ground when the positions LOCAL and LOC DSBL are selected. Enables all the dc voltage outputs of the
power supply.

STANDBY (L)

BATT MON

From the central panel keyswitch S1-B. Set to ground when position STDBY is

selected and disables the logic module dc voltage outputs (+5V, +15V, —15
V). Fan and memory voltage outputs (+5 B, +12 B, —12 B) remain enabled.

From the power supply. Controls the BATT indicator on the control panel when

the H7750-AA, -AB battery backup unit is included in the system.

3-1

BAIliI-AA,-AB MOUNTING BOX
H7140 -AA, -AB

DC ON (L)

CONTROL
PANEL

STD BY (L)

POWER

SUPPLY

BATT MON

AC LO
DC LO
LTC

POWER REQUEST

CPU
AND

BOOT ENABLE *

EXPANDER
BACKPLANES
+5.1V @120A

INPUT

POWER

120/240V |cONTROLLER

POWER REQUEST

SWITCHED AC _

POWER 50"‘"/60
Lz |872-D.E

)
UNSWITCHED AC

LOGIC

VOLTAGES

SHUTDOWN (L)

120vE5

MEMORY

VOLTAGES

-15.0V @ 3A

+12.0V

DC ON (L)

+15.0V @ 3A

_120vV@ 1A

+5.1V @10A

BATTERY

BACK-UP

+BATT

H7750.AA,

| CHG MODE

UNIT

-AB, -AC,
-AD

MONIT ENAB
BATT MON
_ MEMDC LO

35V
FAN BUS

FAN
ASSEMBLY

M
N

+bVB

NOT SUPPLIED
TO EXPANDER BACKPLANE
TK-3493

Figure 3-1

Power Supply, External Signals and Voltages

In addition to the output voltages from the power supply, several signals are transferred between the
power supply and the CPU and expander backplanes. Table 3-2 lists the signals and their functions.
3.1.1.2 [External Voltages and Signals - The 872-D, -E power controller distributes and controls the ac
input voltage to the power supply and other units. The power controller contains a circuit breaker that
can remove all power from the switched and unswitched power receptacles. Control signals from the
power supply can also remove the ac power from the switched receptacles. Table 3-3 lists the control
signals and their functions.

3.2

POWER SUPPLY OPERATIONS

Figure 3-2 show the interconnections of the circuits and modules within the H7140-AA, -AB power
supply. The input voltage is selected by switch S1 which is located at the rear of the power supply. The
ac voltage is received by the input assembly which performs the function of a voltage doubler when the
120 Vac input is selected, and of a full wave rectifier when the 240 Vac input is selected. The dc outputs of the input assembly provide the voltage to the memory inverter module, to the logic inverter
module, and to the bias and interface module via the mother module. The bias and interface module
generates the bias voltages required by the regulators, the voltage generator circuits, and the fans. Figure 3-3 is a functional block diagram of the power supply.

Table 3-2

Signal

ACLO

Backplane Signals

Function

From the power supply. Asserted to indicate to the processor and bootstrap device logic that the ac power, as measured by the 300 Vdc bus to the power supply, is not within required limits.

DC LO

From the power supply. Asserted to indicate to the processor, memory, and device interfaces that the dc power from the power supply is not within required
limits.

LTC

Line Time Clock. From the power supply. Asserted every cycle of the line power to indicate real time to the processor.

BOOT ENAB

From the power supply. Asserted to enable the bootstrap loader program to occur when power is applied to the system. If the content of main memory has
been maintained by the battery backup unit after a power failure, a power
failed restart sequence can be initiated instead of the power-up reboot.

Table 3-3

Signal

POWR REQUEST'
SHUTDOWN

Power Controller Signals

Function

From the LOCAL or LOC DSBL position of the keyswitch on the CPU control

panel. Set to ground to enable the ac power at the switched receptacles.

From the overtemperature sensor in the H7140-AA, -AB power supply. Set to

ground during an overtemperature condition to remove the ac power from the
switched receptacles.

3-3

INPUT ASSEMBLY (7016476)

LINE FILTER
FL1

INPUT

POWER
—

CABLE

CB1

L o~

—

AC HOT

AN\~

L_‘ }__l

5 o

300 vDC

{

230V 115V
[

o—

AT~

p-€

)

PWR REQUEST

RTN

160 vDC

Cg_____

SHUT

DOWN

T
300V

___ J

D
(D
D | G

YD ST

RTN

L ______J

OOOO

)
TK-4926

FIG. 3-2 (SH2)

Figure 3-2

H7140-AA, -AB Power Supply Interconnection Diagram
(Sheet 1 of 3)

FIG. 3-2 {SH1)

FIG. 3-2 (SH3)

q)q)<p<;><;><;><;><;><;> ©
=R
R

_S)?
%DCP@ GP
J
. |
e

1]Ja

RIN—I 7

150V — 5

2 F—BATT MON

4 —sTDBY

ASSEMBLY

{ NO. 7016487 )

I—& 2 ———I
N

MEMORY

br—+5v

G-¢

(54]3605)J

s10} —
J1

Z 0o

}Hl

LOGIC INVERTER CONTROL MODULE

A ®

HEAT

]susz

INTERFACE

229
B8vd,_,

£58e

=S g Z >

MEMORY

| +35 BUS

REGULATOR

RTN

MODULE
(5413607)

H7750-BA,-BB
BATTER BACKUP UNIT

)

J11

J11
-

¢———J

TO J1 ON CPU
BACKPLANE

00O

]

;

1 J1

TO
P1OF CABLE
ASSEMBLY NO. 7016887

49 J10 J11

a @

J2
L
H |oi

[2 34 56 7 8 91011213 [t 23456 6 7 8 9101112131415] |

ggugi%ngNJl\?E%NI’g;L‘Jz

n4l3

a <

ore
M

POWER DISTRIBUTION MODULE (5413832)
3

|3
I

78 9101112131415}
~

EEEEEEEEEEEREN
R

[+ 23745 6

(5413601)

SYNC

ASSEMBLY | 3

MODULE

RECT

jaus1

BIAS &

LOGIC INVERTER MODULE (5413599)

(5413603)

TB2

INVERTER

MODULE

—

TB1

7:]_GND

L 10]—

300V

AC—] 1

5 —bcon

CIM CABLE

300V
— 3

3 |—KEY
10 P1

TB1

300V RTN

|, MOTHER MODULE (5413615) 5 P

([T} —sooT enas

DIO

@ u

J3**

| |

Jax

DD1 1-CK,—DI?BACKPLANE
TK-4925

Figure 3-2

H7140-AA, -AB Power Supply Interconnection Diagram

(Sheet 2 of 3)

)

rBUTPUT ASSEMBLY (7016054)

-I

ala

=l
3

+5V BUS BAR

oz1fil
1|‘L |

c
-/

..—NW\—l.r-

= 5413663

?mfi

—¥g

._J
|
J

_F&L_ _

| 41 3663-'

7171k

TK-4924

Figure 3-2

H7140-AA, -AB Power Supply Interconnection Diagram

(Sheet 3 of 3)

BATTERY BACKUP

—~

DC ON (L)
GND BUS 3

THERMAL

BCON (L)
FROM
CONSOLE
§ <« BATT MON

-_E

SHUTDOWN
>

S RFACE

CONTROL

POWER

CONTROL

THERMAL SHUTDOWN
BOOT ENABLE

BUS1,2
0

LINE TIMING CLOC } PLANE
K

BACK-

MEM DC LOW

+5 VB

STDBY (L)
L

BATTERY

SQ?TK UP

DC LOW

AC LOW

LOGIC INVERTER ON L

* LOGIC

—15V

FROM

BATTERY
BACK-UP

L-¢

UNIT

CHG MODE

+300V

| MONITOR ENABLE

VOLTAGE

BIAS

RELAY

INPUT

DRIVE

ASSEMBLY

+300V

VOLTAGE

| GENERATION|

GENERATION

V BIAS (+12V)

PRIMARY
POWER
SOURCE

115/230 VAC, 60 HZ, 1&

VOLTAGE
|gyn
C,
GENERATION

+300V
MEM INV ON L
MEM PWR OK (L)

BATTERY

+15V @ 3A

—15V@ 3A
5V @10A
+5VB

12V @1A

+12V @5A
MEM

+,-- BATT

BATT IN

UNIT

BACK.

PLANE

+5V @120
A

MEM DC ON (L)
FROM

REMOTE SENSE

MEMORY

]

SENSE

+5V RETURN

<
+150V

FROM

+5V REMOTE

MEM DC ON (L)
DC LO®THERMAL SHUTDOWN (L)

> f/gT_TAGE
FAN
GENERATION | BUST.2

FAN

ASSY

TK-3606

Figure 3-3

Power Supply Functional Block Diagram

3.2.1
Input Assembly
Figure 3-4 is a simplified diagram of the circuit schematic (CS7016476). The ac input from the cable
assembly is connected to the EMI line filter FL1. The output of the filter connects to circuit breaker

CBI1 and to the in-rush current limiting circuit consisting of resistor R1 and relay K1. When ac power is
applied, relay K1 is deenergized and resistor R1 limits the input current. When the dc output voltage of
the input assembly becomes 230 V, the relay is energized, the relay contacts close, and resistor R1 is
bypassed. When switch S1 is in the 120 V position the input circuit operates as a voltage doubler. When
the N terminal of the FL1 is more positive than the L terminal, current flows through CBI1, the relay
contacts, R1, and diode CR1-B to charge capacitor C1. The current return is through S1, CBI, and to
the L input of FL1.
On the next half cycle of the ac voltage, the L terminal of FL1 is more positive than the N terminal.
Current flows through CB1 and switch S1 to charge capacitor C2. The return current is from C2
through diode CR1-A, the relay contacts, R1, CB1 and to the N terminal. Once relay K1 is energized,
the charge across C1 and C2 is approximately twice the peak value of the input ac voltage.
When the switch S1 is set to the 230 V position, the circuit provides full wave rectification of the input
ac. With terminal N more positive than L, current flows through CBI1, the relay contacts or resistor R1,
diode CR1-B, and charges capacitors C1 and C2. The return current is through CR1-D, CB1, and the L
terminal.
On the next half of the ac cycle terminal L is more positive than terminal N. Current flows through
CBl, diode CR1-C, and again charges capacitors C1 and C2. The return current flows through CRI1-A,
or the relay contacts, or R1, CB1, and terminal N.
3.2.2 Bias and Interface Circuits
Figure 3-4 shows the functions associated with the bias and interface module. The signals and voltages
developed by this module are transferred through the mother module to the other circuits in the power

supply. The bias and interface module monitors the voltages and signals and controls the power supply
operation.

3.2.2.1 Bias Voltage — Two bias voltages are developed and distributed to the modules in the power
supply. Sheet 1 of Figure 3-4 shows the circuits used to generate the +12 V and —15 V bias. The
+300 V from the input assembly is switched at a 20-kHz rate at transformer T1, mounted on the
mother module. The switching circuit is located on the bias and interface module. The output of transformer T1 is rectified and filtered to produce the two bias voltages +12 Vand —15 V. The +12 V bias
voltage is applied to relay K1 of the input assembly. When the RELAY DRIVE signal from the bias
and interface module is asserted, the relay is activated and the relay contacts bypass the series limiting
resistor in the ac line.
3.2.2.2 DC Voltage Monitoring — Sheet 2 of Figure 3-4 shows the circuit used to monitor the dc voltages developed by the input assembly circuits. The +300 Vdc is applied as an input to the +300 V
monitor circuit. When ac power is initially applied to the power supply, relay K1 on the input assembly
(Figure 3-2) is deenergized and allows the input ac current to flow through the current limiting resistor
R1. When the dc voltage to the 300 V monitor circuit becomes 230 V or greater, the output of the relay
drive current energizes relay K1 and the relay contacts bypass resistor R1.
3.2.2.3 Normal Operation — When the keyswitch on the front panel is set to the LOCAL or LOC
DSBL position, the DC ON (L) signal to the bias and interface module (Figure 3-4, sheet 3) will be
low. This signal is applied to the turn-on control logic to produce a low LOGIC INV ON L signal. The
LOGIC INV ON L signal is used to enable the +5 V, 415 V, and —15 Vdc outputs of the logic

inverter control module. The DC ON (L) signal is also used to enable the MEM DC ON L and the
MEM INV ON L signals which generate the +5 V, +12 V and —12 V memory voltages.

3-8

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MOTHER
MODULE

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TK-3510

Figure 3-4

Bias and Interface Circuits, Block Diagram
(Sheet1 of 4)

MOTHER

MODULE

(5413615)

17 AA
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BIAS & INTERFACE MODULE (5413605)
ook
<'N

GEN

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SH1

|
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(FIG. 3-2, SH1)¢

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300V OK

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N
7

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ét—. BACK-

TO CPU

22 él—u
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TK-3507

Figure 3-4

Bias and Interface Circuits, Block Diagram
(Sheet 2 of 4)

872-D,-E
PO WER

CONTROLLER— 5
_% 5

MOTHER MODULE

BIAS & INTERFACE MODULE (5413605)

(5413615)

>_
Ja

MEMORY REGULATOR

MODULE (5413607)

nc——> | A

J10

DC LO
THERMAL

MEMORY INVERTER

MODULE (5413603) nc—

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ODULE

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|
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OL

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Wl | MOTHER MobpuLE
(FIG.313)
(5413615)

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24 [ 070

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MEM INV
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LI{ MEM PWR OK

TO LOGIC VOLTAGES

GENERATION

MEMORY VOLTAGES

GENERATION

4 | > 5413607)

CONTROLLER

<51

Figure 3-4

MOTHER MODULE

Bias and Interface Circuits, Block Diagram
(Sheet 3 of 4)

BIAS 8 INTERFACE MODULE (5413605)

(5413615)

MOTHER

MODULE

(5413615)

MEMORY
POWER

MONITOR
MEM'

FROM OK
o| (L) J6
(Fi6.37) 228
"

BATTERY{% <
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|

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'

—|

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TM 02, 07
{FIG.36)

GENERATION—2| v é
(FIG.3-7)

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SH2
E17

FROM

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(FIG.3-45H1) ——|

C12,C20

R79

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MEM

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BATT MON

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UNIT

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FAN V

GEN

(F1G. 3-13)

Figure 3-4

DCLO

TK-3498

Bias and Interface Circuits, Block Diagram
(Sheet 4 of 4)

3-11

3.2.2.4 Standby Operation - When the keyswitch on the front panel is set to the STDBY position, the
STDBY (L) signal to the bias and interface module becomes low. This signal is transferred through the
mother module to the turn on control logic. The MEM DC ON L and MEM INV ON L outputs generated during normal H7140 operation remain asserted and thus enable continued operation of the memory voltages and fan voltage generation circuits. The LOGIC INV ON L output however becomes unasserted during standby operation. This inhibits operation of the logic voltages generation circuit.
3.2.2.5 Temperature Sensing — The temperature sensor (S1), mounted on the output assembly heat
sink, has normally open contacts that close during an overtemperature condition. When the contacts

close, a grounded input is applied to a temperature monitor circuit in the bias and interface control
module. The THERMAL SHUTDOWN (L) signal inhibits the generation of MEM DC ON L, LOGIC INV ON L and MEM INV ON L.
3.2.2.6

Line Time Clock (LTC) Signal — The LTC signal is generated by monitoring the ac line fre-

quency from the input assembly. The LTC output is a square-wave pulse synchronized with the frequency of the input ac (47 to 63 Hz) and isolated via photo transistor E14. The LTC signal is distributed through the mother module to the CPU and expander backplanes.
3.2.3 Memory Voltage
The memory inverter module and the memory regulator module generate and distribute three memory

voltages (45 B, +12 Vand —12 V) to the CPU backplane. The memory inverter module converts the
300 Vdc supplied by the input assembly into +35 Vdc. The memory regulator module converts the
+35 Vdc into +12 V, —12 V and +5 B. Figure 3-5 is a simplified diagram of the memory voltage
generation circuits.

3.2.3.1
+35 Vdc - The +35 Vdc is produced by a dc-to-ac inverter circuit on the memory inverter
module shown in sheet 2 of Figure 3-5. The inverter receives +300 Vdc from the input assembly and is
switched at a 30-kHz rate by the output of the driver circuit.
The 3524 pulse-width modulator (sheet 1) contains a 60-kHz oscillator which provides the basic switching frequency. The 60 kHz is divided by two and the output is used to control the conduction time of
the driver transistor.
The output of the rectifier filter is monitored by the pulse-width modulator and by the overvoltage monitor on the output sense voltages line. An error amplifier in the modulator compares the +35 Vdc with
the voltage developed by the reference generator. When a difference is sensed between the two voltages, the output of the error amplifier varies the width of the 30-kHz pulse, thereby controlling the
conduction interval of the transistor in the driver circuit.
The overvoltage monitor circuit disables the generation of the +35 Vdc in the event the +35 Vdc is
increased to +48 V or greater. The output of the monitor controls the turn-off enable circuit. The out-

put of the turn-off enable circuit is applied to the inhibit logic which generates the output inhibit signal.
This signal will disable the dc-to-ac inverter when the + 35 V increases to the level previously specified.
The over current monitor circuit senses the current through a transformer in the dc-to-ac inverter. The
+ and — pulse current sense input to the monitor develops a voltage to a comparator. This voltage is
compared with a reference voltage and the output of the comparator controls the operation of a oneshot pulse generator. When the pulse current sense voltage increases due to an overcurrent condition in
the dc-to-ac inverter, an output of the one-shot pulse is produced. The 1.5-ms turn-off signal to the inhibit logic disables the dc-to-ac inverter in a similar manner as the overvoltage condition. The overcurrent monitor continues to generate the inhibit pulses until the overcurrent condition is removed.

3-12

Y
)

MEMORY INVERTER MODULE (5413603)
+12V BIAS

FROM
{FIG. 34, SH1)

+—PULSE CURRENT SENSE

OVER

CURRENT
MONITOR

{200 MS

3524 REGULATING PULSE WIDTH MODULATOR

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l__< : )
e

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V

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(NOMINAL)

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(FIG. 3-4)

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ENABLE

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SH1
at

Q10,

SYNC ENABLE

SH1

SYNC OUT

Q79

i
TK-3500

Figure 3-5

Memory Voltage Generation Functional Block Diagram
(Sheet 1 of 2)

|
]

MEMORY

+,—PULSE

CURRENT

SENSE

INVERTER MODULE (5413603)

MEMORY REGULATOR MODULE (5413607)
+12V

FROM

e
o (L)
DC ON

(FIG.34SH3) TM
—

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158
REGULATOR

(FIG. 3-6)

R&L%’?SR

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FILTER

TRANSFORMER

(SH 2)

+5VB

SH2

BATTERY

* BACK-UP

T3
UNIT

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H7750
+35V

+300V

-3

+5V @ 10A

+12V SHUTDOWN

OUTPUT SENSE VOLTAGE

BLANKING

MEM PWR OK (L)

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cLock

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+12v @5a (FIG. 3-4,SH4)

V REF|

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+35V
t

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5 !

Figure 3-5

TO
BIAS AND

» |INTERFACE
To

(FIG.3-7)

BACKPLANE
+12v

SHUTDOWN

V REF

—12B
REGULATOR

(FIG. 3-8)

CLOCK

_12V @1A
)

BLANKING
+35V

TK-3501

Memory Voltage Generation Functional Block Diagram
(Sheet 2 of 2)

3.2.4 Memory Voltage Regulators
The memory regulator module, shown in sheet 2 of Figure 3-5, supplies the three memory voltages to
the backplane. The 435 Vdc is supplied to each of the voltage generators and the memory output voltages are controlled by the conduction times of the three independent switching regulator circuits.

If the H7750 battery backup unit is installed when the ac power fails, the 435 V is supplied by the
H7750 unit. This ensures that the memory regulator module continues to generate the +5 B, +12 V,
and —12 V to memory and that the bias and interface module continues to generate power for the fans.
3.2.4.1
+5 B Regulator Circuit — Figure 3-6 is a block diagram of the +5 B regulator circuit. The +5
B is generated from the + 35 V by the series switch circuit consisting of transistors Q5 and Q6, and the
charging circuit consisting of diode D4, choke L1, and C4. When QS5 and Q6 are off, the stored energy
in L1 provides the current to the load.
The switching circuit is controlled by transistor Q11 which is switched on by the output of the pulsewidth modulator E7. The pulse-width modulator is driven by the clock-pulse generator E9 which triggers the one-shot pulse generator ESB. The pulsed output of ESB provides the basic timing of the power
supply.
The +5 B output current is monitored by the overcurrent comparator El. If excessive current occurs
on the +5 B output, comparator E1 turns off the series switching circuit to open and prevent an overload condition on the +5 B power supply.

The overvoltage circuit, consisting of thyristors Q3 and Q4, monitors the voltage at the 45 B output.
When the voltage exceeds a specified level, Q3 and Q4 are switched on and short the output to be
grounded. The overvoltage circuit also causes the series switch to open, preventing the high current
caused by the grounded output from damaging the circuits.

The +5 B output is normally controlled by the pulse-width modulator E7. This modulator provides
pulses of variable duration to the switch control Q11. The pulse widths can vary from 0-13 us at the 30
kHz switching frequency. The +5 B sense comparator monitors the +5-B output and compares the
voltage with V REF developed by the reference voltage circuit consisting of transistor Q9, regulator
E3, and amplifier E6.

The output of the sense comparator E6 varies the dc input to the control input of the pulse-width mod-

ulator. When the + 5 B voltage is lower than the V REF voltage, the sense comparator output causes
the width of the pulses from the modulator E7 to be increased. The series switching circuit is then
allowed to conduct for a longer duration and the +5 B output voltage is increased.

When the output voltage is greater than the V REF voltage, the sense comparator output causes the
width of the pulses from modulator E7 to decrease. This results in a lower +5 B output voltage.

3.2.4.2

+12 B Regulator Circuit — Figure 3-7 is a block diagram of the circuits that develop the +12

B voltage for the memory modules. These circuits operate in a similar manner to the circuits described
for the +5 B. The +35 V is converted to + 12 B by the switching transistors Q7 and QS8, the flyback
and averaging circuit D6, L2, and C11. The overcurrent circuit E9 and the overvoltage circuit Q2, Q26
and diode D36 provide the overload protection for the +12 B power supply circuits. The pulse-width
modulator E10 is triggered at a 30-kHz rate by the clock-pulses from the +5 B output (Figure 3-6).
The blanking pulse prevents switch control Q10 from conducting until 10 us after the leading edge of
the pulse from the pulse-width modulator has occurred. This allows the pulse width to be reduced to
zero when required.

3-15

BIAS & INTERFACE

MOTHER
MODULE

'MODULE (5413605)

13,

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MEM
BATT

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.

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I Jo

RETURN SENSE

GND =

[

N
-5

(H7750)

823
UAR
S

RTNSENSE - 1O
+12V GENERATION

(FIG. 34, 5H3)

(FiG. 3-7)

LOGIC INVERTER

CONTROL
_Qa 12N, {———*
SYNC

RTN SENSE___

_12v GENERATION
(FIG. 3-8)

TK-3508

Figure 3-6

+35 B Voltage Regulator, Circuit Block Diagram

‘

POWER

MOTHER

MEMORY REGULATOR MODULE (5413607)

MODULE (5413615)

DISTRIBUTION
MODULE

(5413632)

SERIES

+35V

SWITCHING

({FIG. 3-6)

XISTORS

+12V @ 5A

|=*

C11, R36
.

TURN-ON

FROM
F1G. 3-7,3-8

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DRIVE

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a7, 08

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CURRENT|

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SENSE SH2

Lol SENSE

SH2

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+2v

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:

—

11-16

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_]GND l' > 1823 !

INHIBIT
1 roaic

s
TURN
opp

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:

CROWBAR

VOLTAGE

Q25, Q26

INHIBIT

+128
SHUTDOWN

rSiehAL

BASE

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LS 1 25

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|
CLOCK

FROM

(FIG. 3-6)

SH2
E10
024

RESET

L1-¢

TIMER CONTROL

TIMER

CONTROL

]
V REF

sfio

E2, E6

R109

D14, D16

MEM

PWROKI(L)

TO BIAS AND

i
|

INTERFACE
L» \ MODULE

>__’

3-4, SH4)
(FIG.

AAA-

TK-3504

Figure 3-7

+12 B Voltage Regulator, Block Diagram

The +12.B SHUTDOWN level from the + 5 B regulator circuit disables the generation of the +12 B
“voltage when the +5 B is not within the preset levels, and provides the power generation sequence
required by certain devices.

The 412 V voltage comparator E6 monitors the + 12 B output voltage and compares it with the V
REF level generated on the +35 B regulator (Figure 3-6). The comparator output controls modulator
E10 in a similar manner to modulator E7 in the 4+ 5 B regulator. The 412 B comparator E2 generates
the MEM POWER OK (L) signal to enable the controlling signals in the bias and interface module.
3.2.4.3 —12 B Regulator Circuit — Figure 3-8 is the block diagram of the —12 B regulator circuit.
These circuits operate in a similar manner to the circuits described for the +5 V regulator. The +35V
is converted to the — 12 B voltage by the operation of the switching circuit consisting of transistors Q13
and Q14, and by the charging circuit consisting of diode D3 and choke L3. The negative voltage is
developed by L3 which is connected to ground instead of being in series with the output. The overcurrent circuit E6 and the overvoltage circuit consisting of Q6, Q12, and D18 prevent damage when the
output voltage or current exceeds the preset levels.

The pulse-width modulator timer ES8 is also triggered at a 30-kHz rate by the clock pulses from the +35
B regulator circuit. The blanking pulses perform the same function as the +12 B regulator circuit.

The duration of the pulses from pulse-width modulator ES is controlled by the output of sense amplifier
E6. The +12 B SHUTDOWN level will also disable the generation of the +12 B voltage when the
— 12 B regulator voltage is not within specified levels.
3.2.5 Logic Voltage Generation
The logic inverter module, the logic inverter control module, and the output assembly generate the voltages used by the CPU modules in the system. The output voltages are +5.0 V at 120 A*, +15V at 3
A, and —15 V at 3 A and are distributed to the CPU backplane and to any additional backplanes.
Figure 3-9 is a functional diagram of the circuits used to develop the logic module voltages. The logic
inverter module receives + 300 V (nominal) from the input assembly. This input is pulsed by a variablewidth pulse generated in the logic inverter control module. The logic inverter module output is 30 kHz
power that is converted to three logic voltages. The main output is +5.1 V at 120 A. Two regulators on
the logic inverter control module convert the 30 kHz power to 415 V and —15 V logic voltages.
The logic inverter control module receives a +5 V REMOTE SENSE signal from the +5 V at the
CPU backplane. This signal is applied to the input of sense amplifier E2, the output of whichis +2.5V
(nominal). Within the 3524 pulse-width amplifier, the +2.5 V and a reference voltage are applied to an
error amplifier. A comparator in the 3524 produces a pulse, the width of which is proportional to the
error amplifier output. The comparator output is gated at 30 kHz and applied through drivers to a
switching transistor in the logic inverter module.

The switching transistors Q2 —5 are configured in an H-forward converter circuit that converts + 300
V (nominal) to three logic voltage outputs.

*The 5 V, 120 A output must be derated according to the following formula if the =15 V current exceeds 1 A:

I=120A — S0 —1) + (I —1)]

(+15) (—15)

Example: If the +15 V and —15 V are fully loaded to 3 A each, the 5 V output would be derated to 100 A.
I=120A — [3=1)+ 3—1)] = 100
A

3-18

MEMORY REGULATOR MODULE (5413607)
,

2 AMP

SERIES

N\
e

XISTOR

SWITCHING

TURN-ON 33?55
PULSE

AMPL

BLANKING

ROM

SIGNAL

|—————

{FIG. 36) §

SH3

ais

MOTHER

RECT.

IFIER

—_12V e 1A

[=ef EILTER

D3
L3

ons
Q13,14

CROWBAR

]

INHIBIT
|

SH3

RESET

Q20

VoLt
SENSEAGE|OVERV
SH3

TURN

Qg,
D18 12

OFF

OVER

TURN

TIMER

CLOCK

POWER

MODULE

DISTRIBUTION

(5413615)

17,

-MC()5D‘%J113532)

i |$<0

o J8

—12vB

J1
INHIBIT

17
8

—12v

é»BACK-

PLANE

OVER|

CURRENT | OFF
> 25';‘55

SH3

BIAS

Q15,19

INTERFACE
MODULE

{5413605)

R33

—12B SENSE

-l

TIMER

61-t

Sl -

[

|
32

+12V

conTRoL | SHUTSHUT

SH3

V REF

E";.gfi

R77
Ve

\RTN SENSE

L
s (FIG37)

+12V GENERATION

TK-3509

Figure 3-8

-12 B Regulator, Block Diagram

ONOC

LOGIC INVERTER CONTROL MODULE (5413601)

+12V BIAS

FROM

FIG. 34 (SH 1)
CROWBAR

GEN

CROWBAR GATE

SH1

D 35,08

+, — PULSE CURRENT SENSE

CURRENT
MONITOR

sH1

€4

D29, D30 | SIGNAL

SH1

D43, D50

Q14,018,021

SH1

+5Y BUS/-

BACKPLANE

REMOTE

SENSE

16|

FREQ COMPENSATIO
-

NSATION

SENSE

+2.5V (NOMINAL

AMPL

2;”

SH1

an.a22

COMPARATOR

)

REF V GEN

| o

v GEN [NY 12
REF

;Se\fino
SENSETE
"]

oriver

13,15

+5V

Q1,09

RTN

3524 PULSE WIDTH AMPLIFIER SH1, E3

INHIBIT

TURN-OFF

OFF
TURN
ENABLE

FROM

OUTPUT INHIBIT

ERROR

VOLTAGE N

AMPL

DRIVER

14 JKHZ

OVER-

L1111

0c-t

=
FROM

30 KHZ

DIVIDE-BY-

SYNC

R57

AMPL
EXT

SYNC

COUNTER

SH1
Q13

REGULA.
TORS

SH1

Q4,010

+15V ENABLE

ENABLE
SH1
Q2,03

15V ENABLE

FRO
(FIG. 3-4, SH3)

TURN-ON
CONTROL

LOGIC
INV

ON L

(FIG. 3.2)

Figure 3-9

Logic Module Voltage Generation, Functional Diagram
(Sheet 1 of 2)

{FIG.36)

SYNC (IN)

FROM

INPUT ASSEMBLY
=1

L‘“’ é bobbTd

c15

i
+—PULSE

CURRENT

SENSE

LOGIC INVERTER MODULE (5413599)

OUTPUT ASSEMBLY

(7016054)

CROWBAR GATE
PULSE

CURRENT

DC-TO-AC
CONVERSION

SENSE
XFMR

SH1

T1, E4
TURN OFF

{SH1)

XISTOR

T2.74

COLL, BASE

( )

SWITCHING

XISTOR

Q2-05
D12-D19

(F1G. 3-10)

RESET

30 KHZ

> +5Y

GEN

DIODES

+300V

+5V @ 120A

c1.c2

+5V @ 120A

(SH1)

120v

b7.D8

30 KHZ

rLOGlC INVERTER CONTROL MODULE (5413601)

8155,\}/

V RAMP

+15V ENABLE

BUS

0
15Ve LBAcK-

PLANE

o (F1G.312)

O
( )

SYNC ENABLE

|
FROM

-]
>

—15V

GEN

(FIG. 3-11)

~15V

+12V BIAS

TK-3503

Figure 3-9

Logic Module Voltage Generation, Functional Diagram
(Sheet 2 of 2)

3.25.1
435V at 120 A Logic Power — The output assembly, shown in Figure 3-2 (sheet 3), provides
the transformer coupling, LC filtering, and rectification for the main +5 V at 120 A output. In addi-

tion, it consists of a snubber module and crowbar circuit. The input transformer also provides 120 V, 30
kHz to the +15 V and —15 V generation power supply circuits.
3.25.2
—15V Logic Power - The —15 V power for the logic modules is generated by the circuits
shown in Figure 3-10. The logic inverter module generates a — 15 V output by a series switching transistor that is controlled via a pulse-width modulated negative feedback loop.
The 30 kHz, 120 V from the main inverter module is applied to series switching transistors Q7, Q8.

These transistors are controlled by a voltage sense network, error amplifier, pulse-width control, and
drive control. The voltage sense network, consisting of R47, R89, R92, and R93, is connected to the
—15 V input and the filter choke output. One input to the error amplifier is from the voltage sense
network. The other input is a voltage reference. The error amplifier output modulates one input of the
pulse-width control consisting of comparator E1, R48, and R90. The other input is a ramp voltage (V
RAMP). The comparator produces an output that is proportional to the input error signal, which causes
the base drive transistor to turn the series switching transistor on for the required time to maintain the
output voltage at —15 V.

3-21

LOGIC INVERTER CONTROL MODULE (5413601)

LOGIC INVERTER
MODULE (5413599
TB2

D6
34

—18VINPUT
CURRENT

{HIGH)

SWITCHING

SENSE
s

QUTPUT
ASSEMBLY

(FIG.3-2,SH 3)

—15V INPUT
{LOW)

LOGIC

"
RTN
.

VOLTAGE

ERROR
AMPL

i
>

SH2
>

Vv REFI
+12V BIAS

Rs2

—»] CONTROL |

SH2

V RAMP
SYNC

SH2

BASE
DRIVE

E?S'C

RESISTOR

a9
INVERTER

ENABLE

—*

sH2
Qi7

SYNC ENABLE
_ TO

CROWBAR

GEN

-t

(FIG. 3-12)

—15V ENABLE

(SH2)

—15Vv
25 n<__TO

> '3;3:'3;?,
—

C5,C6

SENSE
SH2

POWER
DISTRIBUTION
MODULE

—15V ENABLE

E1, C27,

R49
FILTER

Lai

J1
—15V

CHOKE
SH2

BACK-

PLANE

CURRENT

25,

(5413632)
—-16V

TK-3499

Figure 3-10

-15 V Power, Functional Diagram

The —15 V regulator contains overcurrent and overvoltage circuits. They function similar to those in
the memory regulator module.

3.2.5.3 +15V Power — The logic inverter module generates a + 15 V output, which is similar to the
operation of the —15 V circuit. The major functional difference is the location of the filter choke in
both circuits. Figure 3-11 is the functional diagram for the 415 V power.
3.2.6

Fan Voltage Generation

The bias and interface module shown on Figure 3-12 contains a fan voltage generation circuit that generates a 35 V, square-wave power for the fan assembly. The circuit consists of an oscillator, a divide-bytwo counter, output control, and output drivers. It functions during normal and standby operation of the
power supply and also when the power supply receives power from the battery backup unit.

During normal and standby operation of the power supply, the fan voltage circuit receives a +35 Vdc
input from the memory inverter module. During battery power backup mode, it receives a +35 Vdc
input (MEM BATT IN) from the battery backup unit (H7750).

The 435 V input is applied to a free-running oscillator (E12) via an R-C network (R34, R32, R40) that
establishes the oscillator nominal frequency at 150 Hz (for a nominal 435 V input). The oscillator
output is applied to a divide-by-two counter (E8). The 75-Hz signal output of E8 is then applied to the
output control and drivers. The square-wave output of the drivers is applied to the fan assembly.
3.3

872-D, -E POWER CONTROLLER FUNCTIONS

The 872-D, -E power controller unit controls and distributes the AC power to the units within the cabinet. Figure 3-13 is a simplified diagram of the components and circuits within the unit. The 872-D, -E
provides three dual switched receptacles that can be remotely controlled, and one dual receptacle that
is controlled by the circuit breaker on the 872-D, -E.

The unit includes a line filter FL1, a LOCAL/REMOTE control switch S1, and an ac indicator L1.
A power control bus connects the 872-D, -E unit to the BA11-A mounting box and to other units in the
system. Under normal operation, the LOCAL/REMOTE switch S1 is set to the REMOTE position.
Application of ac power to the units connected to the switched receptacles is controlled by the keyswitch on the control panel of the BA11-A. When the switch is in the DC OFF position, the ac power is
removed by the POWER-REQUEST signal to the ac control board Al. In all other positions of the
keyswitch, the ac power will be applied. When an overtemperature condition exists in a unit connected
to the power control bus, the SHUTDOWN signal to the ac control board Al will also runover the ac
power from the switched receptacles of the 872-D, -E unit.

When switch S1 is in the LOCAL position, the external power controller bus signals are disabled and
the ac power at all receptacles on the 872-D, -E is controlled only by circuit breaker CB1. Circuit schematic (C5) 872-0-2 shows the complete internal wiring of the power controller unit.
3.4 H7750 BATTERY BACKUP FUNCTIONS
The H7750 battery backup units are optional and available in the following voltage configurations.
Model

Voltage

H7750-AA
H7750-AB
H7750-AC
H7750-AD

115 Vac/60 Hz
230 Vac/60 HZ
115 Vac/50 Hz
230 Vac/50 Hz

3-23

LOGIC INVERTER

LOGIC INVERTER CONTROL MODULE (5413601)

MODULE (5413599)

182

+15v

;t'g%

Hor———> I8

FROM

+5V

NTY

LOGIC

+15V INPUT (LOW)

SERIES

SWITCHING [TM]

XISTORS

@ 120A

GEN

+15

v | HiGH)
T°
M

SYNC ENABLE

INPUT

310)

MOTHER

(hga[])gé—]%)

VOLTAGE

ERROR

SENSE

AMPL

SH2

R51,R53

R70,R75

»|

CHOKE

SENSE

CONTROL
| |

BASE

DRIVE

CONTROL

Q5.6

2?:
O

Wik

SH?2

SH2

RTN

RESISTOR

SH2

WIDTH

CURRENT

R27

SH2

SH2
V REF

PULSE

FILTER

(E:fs ‘ R72

R6S, RE7

SH2

Q15

+12V BIAS

(%3

V RAMP

+15V ENABLE
CURRENT
SENSE
V REF

ALY

CROWBAR

SE,EN
)gf} CONTROL

CIRCUIT

SH2
Q16

SH2
D6, D9-D12
15V
E ENABLE
+15V

R18-R20
s

ey TO
B3k
26,

SH2

28 H PLANE

E1,C29
R64, R65

POWER

+15v

I
N

|34

413

c.D

26,

csl

DISTRIBUTION
MODULE (5413632)

+15V

|c7
TK-3512

Figure 3-11

+15 V Power, Functional Diagram

BIAS & INTERFACE MODULE (5413605)
o

__{outrut

DRIVERS

DIVIDE.

MOTHER MODULE
+35V

anD
+BAT

—

RUNNING [ty B8

osC

LCLd it
'

MODULE
IR §5|4 1 36]5)>

!
35V, 75H

E12

L 16 BATT IN

R31, R34

13,341\

MOTHER

SH2

J2 MEM

SIRLLAN

150HZ| COUNTER |75 1z CONTROL

FREE-

w5y

OUTPUT

C6, C7

2,22

AR
[0

1BUS 2

FAN

ASSEMBLY
RED

AA, 23

BUST

FANS
>WHT

|
>-l—

MEM DC ON(L)

FROM

(FIG. 34, SH3){

Figure 3-12

DCLO

THERMAL

SHUTDOWN (L)

Fan Voltage Generation, Functional Diagram

872-D, -E POWER CONTROLLER UNIT

LOCAL/REMOTE

SWITCH
o1

BOARD

INDICATOR

AC POWER

LINE

FILTER

CIRCUIT

EREAKER

SHUTDOWN

B NTROL
-

POWER REQUEST

POWER

CONTROL
BUS

RELAY

ONE DUAL
NONSWITCHED
AC RECEPTACLE

THREE DUAL
SWITCHED
"RECEPTACLES

TK-5640

Figure 3-13

872-D, -E Unit, Simplified Diagram

3-25

These units can be installed in the cabinet to provide dc refresh power to the MOS memory in the CPU,
and to provide power to operate the fans in the event of an ac power failure to the CPU cabinet. The
units contain three sealed, 12 Vdc, lead acid batteries connected in series to provide +36 Vdc. The
minimum discharge rates are as follows.
Discharge Time

Watts

5 minutes

360

7 minutes

265

10 minutes

175

20 minutes

The recharge time is 14 to 16 hours. Terminals on the front of the unit allow external batteries to be
connected to increase the operating time.
The + 36 Vdc is supplied to the memory regulator module and to the bias and interface module in the
H7140-AA, -AB power supply. Figure 3-14 is a simplified diagram of the H7750 unit. It consists of a

rectifier circuit, battery charger, voltage regulator, and an output control circuit. An automatic shutoff
circuit disconnects the +36 Vdc output in the event of excessive current drain. The condition of the
battery is monitored by the CPU on the CHG MODE line and MON ENAB indicates when the battery
backup unit is supplying power.

SHUTDOWN
J11

H7750 BATTERY

THERMAL

__J_11 J2,0R J3
, | Roc

SHUT
DOWN

\
VOLTAGE
REGULATOR |

BACKUP

AND J10

, | Gno

r
115/230

vae

1TM F$SE —’I?ANSFORMER

RECTIFIER

CHARGE

RATE

> >OUT::TL

CONTRO

SWITCH

f——— ———

—

3t sear

P CHG MODE

|
MODE
CHG

L s

V REF

+5 VB

MON EN

o—+ RELAY
—»t

J;—3-12v

caste

701452005

-IBATTERIES

-R

TK-5703

Figure 3-14

H7750 Unit, Simplified Diagram

The charging circuit controls the battery charging rate. There are two charging rates: the fast rate is
approximately 500 MA and the trickle rate is approximately 15 MA. The fast charge rate is initiated
during H7750 turn-on and continues until battery voltage increases to +44 V. At +44 V, the fast

charging stops and trickie charging starts.

3-26

3.4.1

Signals and Voltages

The output control circuit monitors four fault conditions.
AC low
thermal shutdown
no regulator output present
battery voltage low

If the 4+35 V from the memory inverter module becomes less than 20 V, the battery backup unit

switches the batteries on.

3.4.2

Battery Backup Operation

The rectifier and regulator supply the charging current and a relay connects the batteries to the
charger. The output control circuit connects the batteries to the memory regulator in the H7140 power
supply. The rectifier operates from the ac input and supplies a full charging current until the battery
voltage reaches approximately 90 percent of its full charge rating. After this level, the charge rate
switch supplies a trickle charge to maintain the charge on the batteries. The rate of charging is sensed
to develop the charge mode signal to the H7140.

The memory regulator produces +12 V, —12 V, and + 5 outputs until the batteries discharge below 27
V. A voltage reference is used by a relay in the H7750 to disconnect the batteries from the regulator
and to prevent the batteries from discharging completely. The batteries will also be disconnected by the
output control if the + 35 B signal from the H7140 memory regulator goes to zero volts or if any thermal
switch signals an overtemperature condition.

3-27

CHAPTER 4
SERVICE

This chapter provides the information required to evaluate the performance of the BA11-A mounting
box, to isolate malfunctions in the power supply and associated devices, and to remove and replace
defective units and assemblies.
4.1

POWER CHECKS

The system contains several indicators that can be used to check the ac and dc power to the system.
The 872-D, -E power controller unit contains an ac indicator that is lighted when ac power is applied.
The control panel of the BA11-A also contains a DC ON indicator that displays the status of the dc
voltage from the power supply.
AC Power Distribution

4.1.1

The ac power in the BA11-A system cabinet is distributed from the 872-D, -E power controller, or a
similar power controller unit. The 872-D, -E unit contains three dual switched ac receptacles and one
dual unswitched receptacle. The ac power to the switched receptacles is controlled by the LOCAL/OFF/REMOTE switch on the control panel of the 872-D, -E unit, or, if the LOCAL/OFF/REMOTE switch is in the REMOTE position, by the keyswitch on the front panel of the
mounting box.

4.1.1.1

Initial AC Power Checks — To check the ac power in the system, perform the following checks.

Ensure that the keyswitch on the control panel of the mounting box is in the LOCAL or

Check that the ac indicator on the control panel of the 872-D, -E unit is lighted.

LOC DSBL position.

If the indicator is not lighted, check the main ac power outlet to ensure the ac voltage is
present.

If the indicator is lighted, check that the circuit breaker on the 872-D,-E power controller

unit is in the ON (1) position.

Check that the LOCAL-ON/OFF/REMOTE-ON switch on the power controller is in the

If in the REMOTE-ON position, set the switch to the LOCAL-ON position.

7.
8.

LOCAL-ON or REMOTE-ON position.

If ac power is not applied, remove connector P1 or P2 from the dc power control bus on the

power control unit.

If pin 1 of P1 is open to ground, check the continuity of the power control cable between

connector P1 and P2.

Remove connector P1 from J3 on the rear of the BA11-A mounting box.

10.

If pin 1 of J3 is open to ground, the mounting box wiring is defective.

11.

If pin 2 of P1 in step 7 is grounded, an overtemperature condition exists in a unit within
the
system cabinet or peripheral cabinet.

4.1.2

DC Power Distribution
The dc voltages from the power supply are distributed to the CPU backplane and to any optional
backplanes in the mounting box. The DC ON indicator on the control panel of the mounting box
monitors the dc voltages and provides a visual indication of power failures.

4.1.2.1

Initial DC Power Checks - If a dc power failure is indicated, perform the following checks.

Perform steps 1 through 5 of Paragraph 4.1.1.1.

Measure the +5 V CPU backplane voltage at the connector end of the flexprint cable shown
on Figure 4-1.
CAUTION
When measuring the +5 V bus voltage, do not short
the +5 V bus and ground bus together.

4.2

Measure the remaining backplane voltages at connector Pl of the power flexprint cable
shown on Figure 4-1. Table 4-1 indicates the voltage and signal connections on PI.

If a dc voltage failure is evident, remove and replace the H7140-AA, -AB power supply as
described in Paragraph 4.2.4.

REMOVAL AND REPLACEMENT PROCEDURES

This section describes the procedures for removing and replacing the main units and
assemblies within
the BA11-A mounting box.
4.2.1

BA11-A Mounting Box in PDP-11X44 or Similar Cabinet
In the PDP-11X44 or similar system cabinet, the BA11-AA, -AB mounting box is located

at the top of
the system cabinet. To remove or replace the unit, perform the procedures described in subsequent

paragraphs.

Two types of release mechanisms are in use to allow the BA11-A mounting box

to be raised to the
servicing position. The type mechanism the cabinet contains can be identified by the top cover
configuration as shown in Figure 4-2. The cabinet with the type A release has filler strips
located at the
rear of the unit. The cabinet with the type B release has a one-piece top cover.

4.2.1.1

Mounting Box Removal - To remove the BA11-A mounting box from the PDP-11X44 or
similar system cabinet, perform the following procedures.

Open the rear door of the cabinet. Use a 4.0 mm (5/32 in) hex wrench to release the door
fastener.

Remove the ac power from the power controller by setting the circuit breaker in the OFF (0)
position (Figure 2-7).

4-2

PIN SIDE

SYSTEM BACKPLANE

I
| D——I———V

PIN SIDE

' 0

SLOT

I 0

op--u

10—p——7

IS
|t
I

ot
S

jo—4——n

0 |

l]—lL——M

tp--K

14--c

I
| O=t==F
++—€
01
|
| o In——i—-—o

ROW

| u—il——a

Fol i
h

—1 -

1
>

o —t—e

|—e
-

w—t—e

—t—
N

—_

ROW (A—F)

SLOT
(1-14)

SIDE OF

PIN ROW (1 OR 2)

PIN DESIGNATION
A-V

FLEXPRINT CABLE

{G,1,0,QW,X,Y,Z,OMITTED)

GND
FLEXPRINT CABLE

POWER
FLEXPRINT

CABLE
TK-4381

Figure 4-1

Table 4-1

Backplane Assembly, Pin Designations

CPU Backplane Connector P1, Signals and Voltages
Pin

Function

1-10
11-16
17,18
19
20
21
22
23
24
25,27
26,28

+5B
+12 VB
-12 VB
LTC
BUSACLOL
BOOT ENABL
BUSdcLOL
GND SENSE
+5 SENSE
-15
+15

TYPE A

TYPE B
ONE PIECE CABINET
TOP COVER

FILLER STRIPS

CABINET
TOP COVER

CABINET

REAR

Figure 4-2

Cabinet Type Identification

Remove the BA11-A power cord plug from the unswitched receptacle at the rear of the

power controller.

Cut or release any fasteners that secure the power cord to the cabinet frame.

If the release mechanism is type A (see Paragraph 4.2.1), insert the blade of a small screwdriver into the hole behind the slot which is located at the top right side of the front bezel
(Figure 4-3).
5a.

Release the latch which holds the mounting box by sliding the screwdriver in the direction
shown in Figure 4-3.

5b.

Raise the front of the mounting box until the unit is at an angle of approximately 45° with
the top of the cabinet.

5c.

Loosen the four (10-32) screws that hold the cover brackets to the left and right sides of the
mounting box (Figure 4-4). Do not remove the screws.

5d.

Remove the top cover assembly.

Se.

Lower the front of the mounting box until it is in the normal position and the latch engages.

If the release mechanism is type B, remove the screw (10-32) that secures the top cover
ground lead to the rear cabinet frame (Figure 4-5).
6a.

6b.

Use a slot head screwdriver to release the two captive screws that secure the rear of the top
cover to the cabinet.

Raise the rear of the top cover to release the pins from the spring latch at the front of the
cover.

4-4

JCJL
J L

] L

JC
L

DIRECTION

—
)
JbL
e

]
JJ0L

JL_JL___Jl

)

J
) [

J——JL

J [

1 JC
JJL

| | c—
) C

RELEASE

TK-3458

Figure 4-3

Mounting Box Release Lever, System Cabinet

LEFT COVER

BRACKET

RIGHT

COVER BRACKET

SCREWS

(10-32)

2 PLACES

(EACH SIDE)

TK-4396

Figure 4-4

Top Cover Mounting (Type A)

4-5

CABINET

TOP
COVER

FRONT

CABINET

TOP COVER
..

./.

]

SPRING
LATCH

| |l{ —GROUND
LEAD

REAR

DOOR

COVER

CAPTIVE

SCREWS

#—_ SCREW
(10-32)

TK-5639

Figure 4-5

6¢.

Top Cover Mounting (Type B)

Remove the top cover.
Disconnect the UNIBUS and the I/O cable connectors attached to the modules within the
unit.

At the rear of the BA11-A box, remove and retain the two 1/4 inch nuts that secure the cable
clamp bar to the power supply (Figure 4-6).
Remove the cables from the cable trough in the BA11-A box and feed the cables toward the
rear of the cabinet and away from the mounting box.
10.

If the release mechanism is type A, release the latch and raise the front of the mounting box.

11.

If the release mechanism is type B, locate the left and right slide latches on the angle brackets
attached to each side of the BA11-A unit (Figure 4-7).

11a.

Slide the latches in the direction shown to release the latch from the holding pin.

0000000000000 00O0@®

‘OOOOOOOOOOOO0.0....OOOOOOOOOO{@

® ) @o.ooo{l

CABLE CLAMP

TK-5728

Figure 4-6

12.

BAI11-A Unit Cable Clamps

Raise the front of the mounting box to the maintenance position and raise the safety lever to
hold the mounting box (Figure 4-8).
WARNING

When the gas springs are removed, the safety lever
can not support the weight of the BA11-A mounting
box. The box should be supported by a field service
person while servicing is continued.
13.

Remove the retaining clip from the piston ball connectors of the gas spring on the left and
right interface bracket (Figure 4-9). Use needle-nose pliers to facilitate the clip removal.

14.

Remove the retaining clip from the body ball connector of the gas spring on the right side of
the cabinet.

15.

Support the mounting box.

16.

Remove the ball connectors from the studs on the right side of the cabinet by inserting a
screwdriver blade between the ball connector and the ball stud mounting surface.

17.

Remove the ball connectors from the studs on the left side of the cabinet using the procedure
described in step 15.

18.

At the rear of the cabinet, remove the four (10-32) screws and washers that secure the pivot
bracket to the cabinet frame on the left and right side of the cabinet (Figure 4-9). These
screws can not be reached once the box is lowered.

4-7

LEFT

SLIDE LATCH

HOLDING
PIN

BA11-A UNIT

( RIGHT

SLIDE LATCH

TK-5638

Figure 4-7

BA11-A Type B Box Slide Latch Locations

4-8

BA11-AA, —AB

MOUNTING BOX
RIGHT GAS

SPRING

> Bt

\ N
\

SAFETY
LEVER

TK-4397

Figure 4-8

19.

System Cabinet Safety Lever

At the front of the cabinet, while supporting the weight of the box, release the safety lever
and lower the mounting box to its normal position (Figure 4-8).
CAUTION

When the gas springs have been removed, the mounting box is not properly supported.

20.

At the rear of the cabinet, remove and retain the two (10-32) screws and washers on the left

21.

Grasp the bottom of the mounting box at the front and rear and gently slide the box toward
the front of the cabinet. Lift the back of the mounting box and slide the box forward and

and right side of the cabinet that secure the pivot bracket to the mounting box (Figure 4-9).

away from the cabinet frame.

CAUTION

Removal of the mounting box requires two people
due to its weight, one person lifting from the left side
and one person lifting from the right side of the cabinet.

4-9

SCREWS

BA11—-AA, ' —AB

-—

(10-32)

MOUNTING BOX

2 PLACES

(EACH SIDE)
MOUNTING

BRACKET

SCREWS

LEFT

(10—32)

—"

2 PLACES

INTERFACE

BRACKET

(EACH SIDE) /

LEFT

L GAS
SPRING

RIGHT
PIVOT
BRACKET
PISTON

BALL

CONNECTOR

PISTON

ROD

RETAINER

CLIP
BODY BALL

CONNECTOR

(NOT SHOWN)\

}
TK-3469

Figure 4-9

System Cabinet, Mounting Box Hardware

4-10

ng box to be installed does not have the
42.1.2 Interface Bracket Removal/Installation — If the mounti
interface and pivot bracket mounted on each side, remove the brackets from the box to be replaced
and install, using the following procedures.

the two (5/16 - 24) bolts and
Using a 1/2-inch open or box-end wrench, remove and retain the
left and right side of the
at
s
bracket
the (5/16 - 24) ball stud located on the interface
mounting box (Figure 4-10).

Remove the two bracket assemblies and, using the hardware previously removed, install on

the left and right side of the replacement mounting box. Do not tighten bolts.

Align the top of the interface brackets to be parallel with the top of the mounting box and at

Tighten the two (5/16 - 24) bolts and the ball studs at each interface bracket.

the dimension shown in Figure 4-10.

PIVOT

BRAC{ET

INTERFACE

11.18 CM

/ CKET

(-44|N)‘l

BRACKE

BOLTS

(5/16--24)

//2PLACES

O/ ,
BALL (5/16 — 24)
STUD

BA11-AA, —AB
MOUNTING BOX

(LEFT SIDE)

Figure 4-10

TK-4398

Interface Bracket Mounting

4.2.1.3 Mounting Box Replacement — To install the BA11-A mounting box into the PDP-11X44, or
similar system cabinet, perform the following procedures.

Grasp the bottom of the mounting box at the front and rear and position the box on the
support rails with the front of the unit extending away from the front of the system cabinet.
CAUTION

Installation of the mounting box requires two people
due to its weight, one person lifting from the left side
and one person lifting from the right side of the cabinet.

4-11

Slide the mounting box toward the rear of the unit while lifting the rear of the box to clear
the ball stud.

At the rear of the cabinet, install the two (10-32) screws and washers removed in step 20 of
Paragraph 4.2.1.1 in the angle part of the left and right pivot bracket (Figure 4-9). Do not

tighten the screws.

WARNING
When the gas springs are removed, the safety lever
can not support the weight of the BA11-A mounting

box. The box should be supported by a field service

person while servicing is continued.

Raise the front of the mounting box to the position shown in F igure 4-8 and raise the safety
lever to hold the mounting box in position.
Replace the two (10-32) pivot bracket screws and washers, removed in step 18 of Paragraph
4.2.1.1 into the left and right cabinet frame (Figure 4-9).

NOTE
It may be necessary to shift the position of the
mounting box in a direction that will cause the holes

of the interface bracket to be properly aligned with
cabinet frame holes.
Tighten the screws installed in step 5.

Replace both gas springs removed in Paragraph 4.2.1.1 by snapping the lower ball connectors on first and then the upper ball connectors.
Install the four retaining clips removed in Paragraph 4.2.1.1.
Release the safety lever and lower the mounting box to its normal operating position.
10.

If the release mechanism is type A (see Paragraph 4.2.1), the latch will engage when the front
of the unit is in the normal operating position.

11.

If the release mechanism is type B, press down on the front of the unit and push the slide
latches, released in step 11b of Paragraph 4.2.1.1, forward to engage the holding pins.

12.

Route the cables removed in step 9 of Paragraph 4.2.1.1 through the cable trough.

13.

Insert the cable connectors removed in step 11 of Paragraph 4.2.1.1. into the modules.

14.

Install the cable clamp removed in step 18 of Paragraph 4.2.1.1.

4-12

15.

If the release mechanism is type A, perform steps 5 through 5b of Paragraph 4.2.1.1.

15a.

Install the top cover assembly onto the mounting box and tighten the screws that were

15b.

Lower the front of the unit to its normal operating position until the latch engages.

16.

16a.

loosened in step 5d of Paragraph 4.2.1.1.

Replace the top cover of the cabinet, with the type B mechanism, by inserting the pins

located at the front of the top cover into the spring latches (Figure 4-5).

Lower the rear of the top cover and fasten the captive screws released in step 6b of Para-

graph 4.2.1.1.
16b.
17.

Attach the ground lead removed in step 6a of Paragraph 4.2.1.1.

Replace the BA11-A power cord plug into the unswitched receptacle of the power controller
unit.

18.

Set the circuit breaker of the power controller unit to the ON (1) position.

19.

Close the rear door of the cabinet and set the door fastener, using a 3.9 mm (5/32 in)

wrench, so the door is locked.

BA11-A Mounting Box on Slides

4.2.2

When replacing a BA11-A mounting box that is installed on slides, the index plates attached to the side
of the box may be removed and installed onto the replacement unit.

4.2.2.1

BA11-A Slide Mounting Unit Removal - To remove the mounting box, perform the following

procedures.

1.
2.

Remove the ac power from the power controller by setting the ac circuit breaker to the OFF

(0) position (Figure 2-7).

Remove the BA11-A ac power cord plug from the unswitched receptacle of the power con-

troller.

Cut or release the fasteners or clamps used to secure the ac power cord to the cabinet frame.

At the rear of the BA11-A mounting box, remove the cable clamp bars that secure the
external cables to the unit. Each clamp is held by two 1/4 inch nuts (Figure 4-6).

Insert a small screwdriver blade into the slot in the top right side of the front bezel (Figure 411).

4-13

Release the latch that holds the mounting box by sliding the screwdriver to the left (Figure 411).
Pull the front of the mounting box until it is fully extended and the slide hold levers are
engaged (Figure 4-12).
Remove and retain the four (6-32) screws that secure the top cover to the mounting box.
Remove the top cover.
10.

Remove the UNIBUS cable connector from the backplane, the I/O cables attached to the
console interface module (M7090), and all other cable connectors in the modules.

11.

Route the cables away from the mounting box.

12.

Remove and retain the three (8-32) screws that attach the left and right index plate to the
slide assembly (Figure 4-13).

13.

Remove the mounting box from the slides by lifting the unit until the alignment tabs on the
index plates are free from the slide mounting bracket.
CAUTION
Removal of the mounting box requires two people
due to its weight, one person lifting from the left side
and one person lifting from the right side of the cabi-

—/

DIRECTION

I
J
J L

] C
) [

J
JI

] L

)

]

J |

To—

net.

TK-3458

Figure 4-11

Mounting Box Release Lever Slide Mounted Unit

4-14

CABINET‘RAIL\\\‘

/f—BAH—AA,—ABUNW

PAWL RETRACTOR

]

SLIDE
J//
HOLD

SINGLE

_J/

LEVER

CHANNEL
SLIDE

/- BA1T1-AA,—-AB UNIT

CABINET RAIL

4
PAWL RETRACTOR

/I
«
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4
J

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mJDEHOLDJ/
LEVER

[ ]
DOUBLECHANNEL“j

SLIDE

TK-4393

Figure 4-12

Slide Hold Levers

4-15

8—32 SCREWS

(3 PLACES)

PLATE
SLIDE

MOUNTING

ALIGNMENT

TAB

BRACKET

TK-3486

Figure 4-13

Slide to Index Plate Mounting -

4-16

4.2.2.2

Index Plate Installation - If the mounting box to be installed does not contain a left and right

index plate, the index plates must be removed and replaced.
1.

Remove and retain the pivot screws that secure the left and right index plate to the side of

the mounting box (Figure 4-14).

Remove the index plates.

Position the right index plate on the pawl. The index plate tab will protrude away from the
mounting box.

Insert the pivot screw and tighten.

Perform steps 3 and 4, using the left index plate.

Ensure that the index plate rotates freely when the pawl retractor is released.
RIGHT INDEX

[ PLATE

PAWL—\

_~ PIVOT SCREW

‘
o

1
C———

RETRACTOR

BA11—-AA, —AB MOUNTING BOX
®

RIGHT SIDE VIEW

PIVOT SCREW
LEFT INDEX

PLATE —

I PAWL

—1
O

PAWL

°
BA11—AA, —AB MOUNTING BOX
®

RETRACTOR

LEFT SIDE VIEW
TK-4392

Figure 4-14

Index Plate Mounting

4-17

4.2.2.3 BA11-A Slide Mounting Unit, Replacement — To install the mounting box to the slides, perform the following procedures.
1.

Extend the left and right slide channel to their maximum position at the front of the cabinet.
When fully extended, the slide hold lever will be engaged (Figure 4-12).

Carefully lift the mounting box over and above the extended slides and set the index plate
over the slide mounting bracket on each side of the box (Figure 4-13). The index plate
alignment tabs will engage the sides of the slide mounting bracket.
NOTE
When the slides are fully extended, it may be necessary to force the ends of the slides in toward the sides

of the mounting box during installation.
Insert three (8-32) screws through the left index plate tab and into the threaded holes of the
slide mounting bracket. Tighten the screws.

Perform step 3 for the right index plate.
Replace the cables that were removed in step 10 of Paragraph 4.2.2.1.
Replace the top cover that was removed in step 9, using the hardware removed in step 8 of
Paragraph 4.2.2.1.
Replace the cable clamp bars that were removed in step 4 of Paragraph 4.2.2.1.
Replace the fasteners or clamps that were removed in step 3 of Paragraph 4.2.2.1.

Install the power cord plug that was removed in step 2 of Paragraph 4.2.2.1.
10.

Set the ac circuit breaker on the power controller to the ON (1) position.

11.

Release the slide hold levers on each slide channel and push the mounting box into the
cabinet until the latch engages (Figure 4-12).

4.2.3

Fan Assembly Removal and Replacement
The fan assembly is installed on the right side of the BA11-AA, -AB mounting box and can easily be
removed for servicing. The assembly contains three fans that can be individually removed and replaced. To remove and replace the assembly, perform the following procedures.
1.

In a system cabinet perform steps 1 and 2 of Paragraph 4.2.1.1.

If the release mechanism is type A (see Paragraph 4.2.1), perform steps 5a, 5b, and 12 of
Paragraph 4.2.1.1.

2a.

If the release mechanism is type B, perform steps 6a through 6c, 11a, 11b and 12 of Paragraph 4.2.1.1.
If the BA11-A is slide mounted, perform steps 1 and 5 through 7 of Paragraph 4.2.2.1.

3a.

Release the pawl retractor on each side of the mounting box (Figure 4-14) and tilt the box
90° to the maintenance position (Figure 4-15).

4-18

FRONT

a’

RAIL

CABINET

BA11 MOUNTING BOX *

SCREWS

(6-32)

2PLACES
POWER

CONNECTOR
P1/31

* SLIDE MOUNTED UNIT SHOWN.
FAN ASSEMBLY MOUNTED IN A
SIMILAR MANNER IN THE
PDP-11/X44 SYSTEM CABINET.

Figure 4-15

"\
TK-4399

Fan Assembly Removal

Remove the two (6-32) screws that secure the fan assembly into the side of the box.
Slide the fan assembly away from the side of the box approximately 5 cm (2 in) and disconnect connector P1 from J1.
Continue to slide the assembly away from the box.
NOTE
Any of the three fans can be replaced by disconnecting the power plug on the fan and removing
the four (6-32) mounting screws that secure the fans
to the slide. Use only the specified replacement fan
and mount the new fan to the assembly, using the
hardware removed.

4-19

To replace the fan assembly, slide this assembly into the side of the mounting box, replace
the plug removed in step 4 and the screws removed in step 3.
In a system cabinet with a type A release mechanism, perform steps 12 and 13 of Paragraph
4.2.1.3.

8a.

In a system cabinet with a type B release mechanism, perform steps 12, 14, 19a and 19b of
Paragraph 4.2.1.3.

8b.

Perforr

Ifthe BA11-A is slide mounted, release the pawl retractor (Figure 4-14) and tilt the box to its
normal operating position.

9a.

Perform steps 11 and 10 of Paragraph 4.2.2.3.

teps 22 and 21 of paragraph 4.2.1.3.

4.2.4

H7140 Power Supply Unit
The H7140 power supply unit is located at the rear of the BA11-A mounting box. To remove and
replace the unit, perform the procedures in the following paragraphs.

4.2.4.1 Power Supply Unit Removal - To remove the power supply,‘ perform the following procedures.
1.

In the system cabinet, perform steps 2 through 4 and 8 of Paragraph 4.2.1.1.

la.

If the release mechanism is type A (see Paragraph 4.2.1), perform steps 5a through 5f of
Paragraph 4.2.1.1.

1b.

If the release mechanism is type B, perform steps 6a through 6d, 11a and 11b of Paragraph
4.2.1.1.

If the BA11-A is slide mounted, perform steps 1 through 9 of Paragraph 4.2.2.1.

Remove the I/O and bus cables from the cable trough at the left side of the power supply
and route the cables over the top of the power supply.

Remove and retain the two (8-32) screws located in each of the two chassis angles at the rear
of the mounting box (Figure 4-16).

If the BA11-A is slide mounted, release the pawl retractor (Figure 4-14) on each side of the
box and tilt the box 90° to the maintenance position (Figure 4-15).

In the system cabinet, raise the front of the mounting box to the position shown in Figure 48 and raise the safety lever to hold the mounting box in position.

Remove and retain the four (6-32) screws that secure the bottom cover to the mounting box
(Figure 4-17). Remove the cover.

Remove and retain the four (6-32) screws that secure the cover plate to the bottom of the
power supply assembly. Remove the cover.

Remove and retain the (10-32) screw that secures the ground lead to the ground bus (Figure
4-18).

4-20

TIOONS

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2 PLACES

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TK-4400

Power Supply Unit, Rear Mounting Screws

Figure 4-16

BA11-A

/ MOUNTING BOX *
FRONT

CABINET

ceoold000fcocooca

RAIL

BOTTOM COVER

SCREWS (6-32)
4 PLACES

SCREWS

H7140 AA—-AB

(6-32)

POWER SUPPLY

2 PLACES
(EACH SIDE)

COVER PLATE

SCREW (6-32)
4 PLACES

—

NOTE:

SLIDE MOUNTED VERSION OF THE
BA11-A BOX IS SHOWN. THE
PDP-11/X44 SYSTEM CABINET
VERSION IS SIMILAR.

Figure 4-17

Power Supply Unit Removal
4-21

TK-4401

BEZEL PC BOARD

(

i
oM

CABLE

= an
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[

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- g f=

FRONT

pANEL\ TU5\8

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faal

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- [ cm

(M9070)

CONSOLE

ASSY

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TERM

BACKPLANE

ggxé\:sv

| /—POWER FLEXPRINT CABLE

CABLE

' /‘GROUND FLEXPRINT CABLE

(J2ANDJ3

I‘lfl\\
=

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b f

=
oo
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LEAD

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sT e

—

|~—SCREW
(10-32)

J2
CABLE

CONNECTOR

GND

9.5 MM (3/8 IN)
2 PLACES

P1/J11
TK-3641

Figure 4-18

Mounting Box, Power Cable Cofinections

10.

Loosen the two 3/8 in nuts on the clamp that holds the ground Flexprint cable to the ground
bus bar.

11.

Loosen the two 3/8 in nuts on the clamp that holds the +5 V Flexprint cable to the +5V bus
bar.

12.

Slide the ground and +5 V Flexprint cables away from the clamps and bend up toward the
backplane.

13.

Remove the power Flexprint connector P1 from the power supply connector J11 and bend
up toward the backplane.

4-22

14.

Remove connector P3 of the CIM cable assembly from connector J1 of the power supply.
Move the tabs on each side of J1 outward, to release P3 (Figure 4-18).

15.

Remove the 3/8 in nut that secures the ground lead of connector P3 to the chassis ground
stud (Figure 4-19).
H7140-AA, -AB POWER SUPPLY UNIT

—

NUT

TK-4405

9.5 MM

(3/8 IN)

Figure 4-19

16.

17.

Power Distribution Panel Connectors
and Cable Assembly

If one or more additional backplanes are mounted in the box, remove the connectors attached to J2, J3 and J4 of the power distribution board. Remove the backplane connectors
from P2, P3, and P4 of the power distribution harness.

In a slide mounted installation, remove and retain the (8-32) screw located on each side of
the mounting box, toward the rear (Figure 4-17).

18.

In a system cabinet installation, remove the side panels of the cabinet.

18a.

Release the safety lever and lower the mounting box so that the (8-32) screws located on
each side of the mounting box toward the rear are accessible (Figure 4-17).

18b.

Remove and retain the two (8-32) screws described in step 18a.
CAUTION
The H7140 power supply assembly will tend to slide
forward when the screws in step 18 are removed.

4-23

19.

Slide the power supply assembly forward approximately 5.0 cm (2.0 in) and disconnect the
fan assembly power cable shown in Figure 4-18 from connectors J2 and J3 (not shown) on
the power supply PC board.

20.

Slide the power supply assembly from the mounting box and away from the cabinet.

4.2.4.2

Power Supply Unit Replacement

With the mounting box in the maintenance position, ensure that the /O and bus cables will
not interfere with the power supply installation.
Slide the power supply into the mounting box chassis until it is approximately 5.0 cm (2.0 in)
from being completely in position (Figure 4-17).

Connect the fan assembly power cable terminals removed in step 19 of Paragraph 4.2.4.1.
In the system cabinet, replace the screws (8-32) removed in step 18a and 18b of Paragraph
4.24.1.
4a.

Raise the mounting box to the maintenance position and raise the safety lever (Figure 4-8).

4b.

Replace the side panels removed in step 18 of Paragraph 4.2.4.1.
If the BA11-A is slide mounted, replace the screws (8-32) removed in step 17.

Replace the backplane connectors removed in step 16 of Paragraph 4.2.4.1.
Replace the ground lead removed in step 15 of Paragraph 4.2.4.1.

Replace connector P3 removed in step 14 of Paragraph 4.2.4.1.
Replace the power Flexprint cable connector removed in step 13 of Paragraph 4.2.4.1.
10.

Replace the +5 V and ground Flexprint cables removed in steps 10 through 12 of Paragraph
4.2.4.1.

Replace the ground lead removed in step 9 of Paragraph 4.2.4.1.

12.

Replace the cover plate removed in step 8 of Paragraph 4.2.4.1.

13.

Replace the bottom cover removed in step 7 of Paragraph 4.2.4.1.

14.

In the system cabinet, release the safety lever and lower the mounting box to the normal
operating position.

14a.

If the release mechanism is type A (see Paragraph 4.2.1), the latch will engage when the front
of the unit is pressed down.

14b.

If the release mechanism is type B, press down on the front of the box and push the slide
latches forward to engage with the holding pins on the left and right side of the mounting
box (Figure 4-5).

4-24

15.

If the mounting box is installed on slides, release the pawl retractor and tilt the box to its
normal operating position (Figure 4-12).

16.

Replace the screws removed in step 4 of Paragraph 4.2.4.1.

17.

Replace the 1/O and bus cables removed in step 3 of Paragraph 4.2.4.1.

18.

If the mounting box is installed on slides, install the top cover removed in steps 8 and 9 of
Paragraph 4.2.2.1.

18a.

Release the slide hold lever on each slide rail and push the mounting box into the cabinet
until the front latch engages (Figure 4-12).

19.

Replace the cable clamp bar removed in step 8 of Paragraph 4.2.1.1.

20.

In the system cabinet, if the release mechanism is type A (see Paragraph 4.2.1), replace the
top cover as described in steps 15a through 15c of Paragraph 4.2.1.3.

21.

In the system cabinet, if the release mechanism is type B, replace the top cover as described
in steps 16a through 16c of Paragraph 4.2.1.3.

22.

In the system cabinet, connect the ac power as described in steps 17 through 19 of Paragraph
4.2.1.3.

23.

4.2.5

If the BA11-A unit is slide mounted, perform steps 9 and 10 of Paragraph 4.2.2.3.

CPU Backplane Assembly

The CPU backplane is mounted on the right side of the BA11-A mounting box. Perform the following
procedures to remove and replace the assembly.

4.2.5.1
1.

Backplane Assembly Removal - Perform the following procedures to remove the backplane.
In the system cabinet, perform steps 1 through 3 of Paragraph 4.2.1.1 to remove the ac
power from the unit.

la.

If the release mechanism is type A (see Paragraph 4.2.1), perform steps 5a through 5f of
Paragraph 4.2.1.1 to remove the top cover of the cabinet.

1b.

If the release mechanism is type B, perform steps 6a through 6d of Paragraph 4.2.1.1 to
remove the top cover of the cabinet.

If the mounting box is installed on slides, perform steps 1 and 2 of Paragraph 4.2.2.1 to
remove the ac power.
2a.

Perform steps 5 through 9 of Paragraph 4.2.2.1 to remove the top cover of the mounting
box.

Remove the I/O and bus cables from the modules in the CPU backplane.
Remove the modules from the CPU backplane.

4-25

NOTE

Observe the module locations so that they can be replaced into the CPU backplane in the same positions.
5.

In the system cabinet, if the release mechanism is type A, press the release lever and raise the
front of the mounting box.

In the system cabinet, if the release mechanism is type B, locate the left and right slide
latches on the angle brackets attached to each side of the BA11-A (Figure 4-7).

6a.

Slide the latches toward the rear of the unit to release the holding pins.

In the system cabinet, raise the front of the mounting box to the maintenance position and
raise the safety lever to hold the box in position.

If the mounting box is installed on slides, perform steps 5 through 7 of Paragraph 4.2.2.1.

8a.

Release the pawl retractor on each side of the mounting box and tilt the box to 90° to the
maintenance position.

Perform steps 7 through 13 of Paragraph 4.2.4.1.

10.

Remove and retain four (8-32) screws used to secure the CPU backplane onto the mounting
rails (Figure 4-20).

11.

Remove the CPU backplane assembly.

4.2.5.2

Backplane Assembly Replacement — Perform the following procedures to install the backplane
assembly.
1.

Install the CPU backplane using the four (8-32) screws removed in step 10 of Paragraph
4.2.5.1. Do not tighten the screws.

In the system cabinet, release the safety lever and lower the front of the mounting box.

2a.

If the release mechanism is type A (see Paragraph 4.2.1), the latch will engage when the box
is in the normal operating position.

2b.

If the release mechanism is type B, press down on the front of the unit and slide the left and
right latches toward the front to engage the holding pins (Figure 4-7).

If the mounting box is installed
on slides, release the pawl retractors on each side and rotate
the box to the normal operating position (Figure 4-12).

Insert a hex-height module into the card guides that are aligned with the first and last slots at
each side of the backplane (Figure 4-21).

NOTE
The backplane assembly can be shifted in position to
enable the module connectors to be pronerly aligned
with the module slots.

4-26

14 SLOT-COLUMN
CPU BACKPLANE

+5 FLEXPRINT

/CABLE

GROUND FLEXPRINT
CABLE

9.5 MM (3/8 IN.

—

NUT

2 PLACES

NUT

9.5 MM (3/8 IN.)
2 PLACES

TK-5018

Figure 4-20

CPU Backplane Assembly Mounting

Raise the mounting box to the maintenance position as described in steps 5 or 6 and step 7 of

Paragraph 4.2.5.1.

Tighten the screws (8-32) installed in step 1.

Replace the Flexprint cables and ground lead that was removed in steps 6 and 7.
Replace the cover plate and bottom cover of the mounting box that was removed in steps 8
and 7 of Paragraph 4.2.4.1.

Lower the mounting box to its normal operating position as described in steps 2, 2a, 2b or 3.
10.

Remove the hex-height modules used to align the backplane.

Replace the modules that were removed in step 4 of Paragraph 4.5.4.1.

4-27

[N
[N [NN
>I

HEX MODULE

COMPONENT SIDE
FRONT
GUIDE

(RED)

REAR GUIDE

{BLACK)

9SLOT
SYSTEM UNIT

TK-4404

Figure 4-21

Backplane Assembly Alignment

12.

Replace the I/O and bus cables that were removed in step 3 of Paragraph 4.2.4.1.

13.

In the system cabinet, perform steps 21 or 23 of Paragraph 4.2.4.2 to replace the top cover of
the cabinet.

14.

If the mounting box is installed on slides, replace the top cover that was removed in step 2a.

15.

Restore the ac power to the unit that was removed in steps 1 and 2 of Paragraph 4.2.1.1.

4-28

4.3 POWER SUPPLY UNIT, COMPONENT LOCATIONS

assemblies,
The H7140-AA, -AB power supply contains an input assembly, three removable module
module
mother
a
contains
also
supply
power
The
4-22.
Figure
on
and an output assembly as shown
es
assembli
module
the
between
ed
distribut
are
voltages
and
Signals
and a power distribution module.
the
to
by the mother module. The power distribution module distributes the signals and voltages
backplanes.

TOP COVER

MEMORY

REGULATOR
MODULE

BIASAND

INTERFACE

MEMORY

INVERTER
MODULE

[T~

MODULE

| LOGIC

inverTer

MODULE

|- LOGIC
INVERTER

INPUT

ASSEMBLY

CONTROL
MODULE

—OUTPUT
ASSEMBLY

TK-5013

Figure 4-22 H7140 Unit Module and Assembly Locations
4.3.1

Input Assembly

Figure 4-23 shows the components associated with the input assembly. This assembly is not removable
as a unit.

4.3.2

Bias and Interface Components

The inter'face and control circuits, the bias circuits, and the fan square-wave voltage circuits are located
on the bias and interface module and on the mother module.
4-29

”

I I

B =—

o--qr—-”—“:r—“:{——l
!

]

A |

Foien N

g;(REAR)

|R
m

O
B

T mebs I el

e
e
e

ER
EEE
T
|

TR L
'

]

__J%__IL_.__JI___!I__J
-

—!I

—”—
Ll

—H_ 1|

CR1

—-

;

~~p4
TK-5014

Figure 4-23

Input Assembly, Component Locations

4.3.2.1
Bias and Interface Module - The main components associated with the interface and control
logic are shown in Figure 4-24. The +12 V and -15 V bias voltages are developed by circuit com-

ponents shown in Figure 4-25 and by components located on the mother module. The fan voltage
components are shown in Figure 4-26.

4.3.2.2 Mother Module - The mother module contains the PC wiring and connectors to electrically
connect the modules and assemblies of the power supply. The module also contains components used
in developing the +12 V and -15 V bias voltages and the +15V and -15 V for the logic modules. These
components are shown in Figure 4-27.
4.3.3 Memory Voltage Assembly
The memory voltage assembly, shown in Figure 4-28, develops the voltages required by the system
memory modules. The assembly consists of the memory inverter module and the memory regulator
module, which are connected together by a mounting bracket.

4.3.3.1

Memory Inverter Module - Figure 4-29 shows the main components associated with the functions on the memory inverter module. This module develops the +35 V used as the source for the
memory voltages generated on the memory regulator module. Transformer T3, which connects to the
memory inverter module, is mounted on the bracket shown in Figure 4-28.

4.3.3.2 Memory Regulator Module - The memory regulator module contains the +5 B regulator, the
+12 B regulator and the -12 B regulator. Figure 4-30 shows the location of the main components on
the module used to produce the +5 B voltage. Figure 4-31 shows the main components used to generate the +12 B voltage. Figure 4-32 shows the main components associated with the generation of the

-12 B voltage.

4-30

4.3.4 Logic Voltage Assembly
The logic voltage assembly produces the voltage required by the logic modules in the backplane. The

assembly shown on Figure 4-33 consists of the logic inverter control module and the logic inverter
module. These modules operate with the components of the output assembly to develop the +5V, +15
Vand -15 V.
4.3.4.1 Logic Inverter Control Module - Figure 4-34 shows the components associated with the reference voltage generation and the voltage sensing.

Figure 4-35 shows the components used to develop the +15 V and the -15 V on the logic inverter
control module.

4.3.4.2

Logic Inverter Module - Figure 4-36 shows the component locations on the logic inverter

module.

4.3.5 Output Assembly
The output assembly contains the high voltage transformer T1 and the rectifier components that

generate the +5 V output. Figure 4-37 shows the location of the components. The snubber module is
located below the transformer T1 and choke L1 and contains the components shown in Figure 4-38.
4.3.6 Power Distribution Module
Figure 4-39 shows the components and connectors on the power distribution module. Connector P1 of
the power distribution cable assembly (DIGITAL No. 7016887) attaches connector J1 on this module.
Figure 4-40 shows the cable assembly wiring.

52\
oOL4| Qs
e \mg::j) €53
i
CONTl_R
E::] flflm

I \% =

L PRy

@m DUJDHU i o

kOfl\E—\—}i%g% OQ::E:]E%
D10 —

s =
L

—
W
i

TEMPERATUR
E | o1
012/(5‘[E=
%[[:/'/ =]J Em Q @:
MONITOR
UJ Dm
T
TT 7

TK-3475

Figure 4-24

Bias and Interface Module, Interface and Control

Components (Sheet 1 of 3)

4-31

MEMORY
POWER

AC/DC
POWER

MONITOR

MONITOR
)

E10

BATTERY {E1""'
BACK-UP
UNIT

/E” }RELAY

os
LT
BOOT

E11

ENABLE ] Q5|

E10

MONITOR

E9-

DRIVE

Q6|

(434

—E14

>CLOCK
GENERATOR

Q24 J

o |
.

E16

C12 D34 C20 E17

R79 D35

+5V POWER SUPPLY

+300V

MONITOR

Figure 4-24

Bias and Interface Module,

Interface and Control

Figure 4-24

Bias and Interface Module, Interface and Control
Components (Sheet 2 of 3)

Components (Sheet 3 of 3)

E13

FREQ

A /
/

DRIVER

o@UIU

~
‘
I E:::] flm
/Rsfl

Q EUF:J m U [Jm E:J E‘:"T'Dfifi[’(_)l’/j;: }OSCILLATOR

TRIGGER

Q15 conTROL

=
=

0 p

R34

o°

TIMER

E15 (555)

[

o 57

15 5t 4

CONTROL

O g:jjgj:jg:j[] Q:J:]UEED‘H:%

RAMP
/014 GEN

~...

OUTPUT

CHOPPER

Pret

(Q16 //@U] B
OUTPUT |

J |
Qg———=

C1Q

Q20—
Figure 4-25

Bias and Interface Module,

Bias Voltage Components

Figure 4-26

Bias and Interface Module, Fan Voltage Components

—-15V

RECTIFIER

D —1—>» ]

—

—3

(:]]
— O3 3

R5\ —1

T1 XFMR

MEMORY INVERTER

MEMORY REGULATOR
MODULE

c28

R 4 \s

‘

+12V

D6 —

//E]l

RECTIFIER | g

)

o}l

TB2 (TB1 REAR NOT
SHOWN)

{
|

L
1

—

]!
|

[

0]
|

|
|

17451%

|
|
|
|

FILTER

1| I

\‘:\@ @1
.

O] il

\/[:

C5{ ¢ TER
-

CAPACITOR

CAPACITORS \ c6

TK-5015

Figure 4-28

TK-3495

Figure 4-27

Mother Module Components

Memory Voltage Assembly Components

CLOCK

GENERATOR

TB1

ey N

(

oo 2~ Uflflfl 100
1
2 —
| S

PWM

ENABLE/

ales

£5C37 cag|
021 E9|/
7028y,N\

3 21

::HCD[:JC:J

—

\/,_I\J

(000EEDU(EDD%IU
D= “Q}flflfi/
fi] T
UO/O“‘ ' INVERTER
S

TURN

St-v

ON/OFF ] 08~

CONTROL | q7

eh€iin
'

===

PN ) I:|

\\\

[—

—

[j\

qunne

~OIeo

/T \ [n:nfit][m \ )

PWM
A U UU
(3524) E1

=
3

[

[T~

=0
B

- _Dis

alo
SYNC
AMPL

218 a5,
N Q12 Q13
SWITCHING
XISTORS

TK-3466

TK-3492

Figure 4-29

Memory Inverter Module Components

Figure 4-30

Memory Regulator Module,
+5 B Components
(Sheet 1 of 2)

TIMER

T
E7

Q17 D16

=] = JE— ey
TURN-ON
PULSE

AMPLIFIER

\
——E6
D17
g3 | REFERENCE

/029 > VOLTAGE
-

GENERATOR

jos

XISTOR {st

SERIES

SWITCHING

OVER

CURRENT

SENSE

*$OPPOSITE
SIDE

*L1D4 C5
RECTIFIER
FILTER
TK-3462

Figure 4-30

Memory Regulator Module, +5 B Components

(Sheet 2 Of 2)

4-36

TIMER

CONIROL
—

D14 Dl15

E’6

TURN-ON
Q18

PULSE

AMPLIFIER

OVER

> VOLTAGE
SENSE

OVER
CURRENT

SENSE

TURN-ON

|F4 FUSE

Q10 PULSE
LEV

AMPLIFIER

Q7 08,

*OPPOSITE

gpe

SIDE

SERIES
SWITCHING

FILTER
TK-3484

Memory Regulator Module,

+12 B Component Locations

RECTIFIER

XISTORS

Figure 4-31

*13
D3
CI10
—_————————

TK-3472

Figure 4-32

Memory Regulator Module, —-12 B Components
(Sheet 1 of 2)

%20

Q19

=1=2

XISTOR

Q13—

el
TURN-ON

> PULSE
AMPLIFIER

Q12

8¢

—Q6

TK-3491

Figure 4-32

LOGIC INVERTER
MODULE

mbflflfil pparps K

Q15

LOGIC INVERTER
CONTROL MODULE

(555)

Memory Regulator Module, -12 B Components
(Sheet 2 of 2)

Figure 4-33

&
|

TIMER

)—

INHIBIT
CONTROL

TK-5016

Logic Inverter Assembly Components

PWM

(555)

/m 012 | REFERENCE

VOLTAGE
U
_C21 | GENERATION
m
/ms
W,

TURN-

OFF
<
CONTROL

C2 D5

OVER-VOLTZTGE SENSING

TK-3460

Figure 4-34

Logic Inverter Control Module, Voltage Reference
and Sensing Components

4-39

BASE
CONTROL
Q19 \

TURN-

OFF

Q16

CONTROL

CURRENT
SENSE
E1

\ mflm

mm:m

Dflm

BASE

CONTROL \\@]
DRIVE

Q15

SERIES

SWITCHING{QG\
XISTORS

Q7 | SERIES
SWITCHING
://08 XISTORS

\Q@5—__
]

—

FILTER
C40 —_

D10—_|

OVER

sz\

SENSE

VOLTAGE{ p14

———C41

L1} FILTER

_ D6

TK-3465

Figure 4-35

Logic Inverter Control Module, -15 V and +15 V

Components

4-40

<P\
oerone! o @@@fi i -\ fi
D16
THRU
D19

]

fDFo

]

LLL1LL
LLL
LN
g8 76 b 4 3 2
2

- _J
TB1

D6
F2

[

L T2\~ ] i

AFCDSF/ _/‘1_ _J
Ol

T4
T3

—

D12

THRU D15

XISTOR

K—-

\\——————\ P
T1

TB2

PULSE

CURRENT
SENSING
TK-3481

Figure 4-36

Logic Inverter Module Components

4-41

CROWBAR
Q1

‘

(]

FILTER ¢

(O)

o) | © >

.’

(¢

55
@

MODULE

éL// D4

C’ |

SNUBBER

Mol

RECTIFIER

T
-

D2 |

TK-3461

Figure 4-37

Output Assembly Components

fIpa

[ID3

(B[::m (Bl:::w
+ C4 +

+C3 +

[|%

L (B:m
C2 +

TK-3464

Figure 4-38

Snubber Module Components

4-42

(AT REAR)

) i|o S
TK-5012

Figure 4-39

Power Distribution Module Components

12345678910 111213]P1

1234lpa

czxah

123 4a]p3

G185

|123 4]r

Pl &)

6285

CABLE ASSEMBLY NO 7016887
TK-5008

Figure 4-40

Power Distribution Cable Assembly Wiring

4-43

3A11-A Mounting Box and

Reader’s Comments

‘ower System Technical Manual

'—BAI 1A-TM-002

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