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Document:	861-A,B,C,D,E,F Power Controller Maintenance Manual
Order Number:	EK-861AB-MM
Revision:	002
Pages:	40
Original Filename:

OCR Text

861 A B,C D E,F

power controller

maintenance manual

digital equipment corporation - maynard. massachusetts

——

861-A.,B,C,D,E,F

power controller
maintenance manual

EK-861AB-MM-002

digital equipment corporation - maynard, massachusetts

TIEEE TR

1st Edition, February 1973
2nd Edition, August 1975

The material in this manual is for informational
purposes and is subject to change without notice.
Digital Equipment Corporation assumes no respon-

sibility for any errors which may appear in this
manual.

Printed in U.S.A.

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

PDP

FLIP CHIP

FOCAL

DIGITAL

COMPUTER LAB

UNIBUS

MASSBUS

ArNEIE

CONTENTS
Page

CHAPTER 1

INTRODUCTION

1.1

1.2.2

GENERAL DESCRIPTION
. . . . . o i e e e e
SPECIFICATIONS . . . o
i
e
e e e e e e e e e e
Mechanical And Environmental
. . . . . . . ..
Electrical . . . . . . v v o e e e e e e e e e e e e

CHAPTER 2

INSTALLATION

2.1

2.4

SITE CONSIDERATIONS . . . . . o it e e e
e e e e e e e e e e
e
CABLES . . . .
e
Input Power . . . . . . . .
Remote Switching Control . . . . . . . .. .
Output Power
. . . . . . o o
e
GROUNDING . . . it it e e e e e e e e e e e
INITIAL OPERATION
. . . . o o it e e e e

CHAPTER 3

OPERATION

3.1

3.1.6

CONTROLS AND INDICATORS . . . . . o it
e e e e e e e e e e
Pilot Lamps
.. .. .. ... ........ e
e e e e e e e e e
Circuit Breaker . . . . . . . . o i o i i e
e e e e e e e e e e e
LOCAL/OFF/REMOTE Switch . ... ... ..e e e e e e e e e
Remote Switching Control Bus Connectors
. . . . . . ... ...
Power Outlets
. . . . v v v i et e e e e e e e e e e e e e e e e
Overtemperature Switch . . . . . . . . . . . o v
o
e

CHAPTER 4

THEORY OF OPERATION

4.1

4.8

GENERAL . . . . . .ttt
e e e e e e e e e e e e
TYPE 861-A CIRCUIT DESCRIPTION . . . . . . . .
TYPE 861-B CIRCUIT DESCRIPTION
. . . . . . . .
TYPE 861-C CIRCUIT DESCRIPTION
. . . . . . . .
TYPE 861-D CIRCUIT DESCRIPTION
. . . . . . . .
TYPE 861-E CIRCUIT DESCRIPTION
. . . . . . . .
TYPE 861-F CIRCUIT DESCRIPTION
. . . . . . . .
PILOT CONTROL BOARD CIRCUIT DESCRIPTION

CHAPTER 5§

MAINTENANCE

5.1

GENERAL . . .
e
e
e
PREVENTIVE MAINTENANCE
. . . . . . .
No Output (Circuit Breaker Tripped)
. .
No Output (Circuit Breaker Not Tripped)
NO Control . . . . i e i e
e e e e e e

1.2

1.2.1

2.2

2.2.1
2.2.2
2.2.3

2.3

3.1.1
3.1.2
3.1.3

3.1.4
3.1.5

4.2
4.3
4.4
4.5

4.6
4.7

5.2

5.2.1
5.2.2

5.2.3

e e
. .
..
. .
e e

e e e
e et
...
e e e

e et e i
e e et e e oo
s e it e e e e
e e e
oo
e e e e e e
e e e e e

1-1
1-1
1-3
1-3

e e e e e e e e e e e e e e e e e o
e e
e e e e e e e e e e e e e
e e e e e e e e e e e e e
e
. v v i i v i
e
e
e e e
e e e e e e e e e
e et e e et e e e e e e e e e e

2-1
2-1
2-1
2-4

e e e e e e e e

e e

2-4

e e e e
e e e
e e e e
e e e e
... ..
e e
e

3-1
3-1
3-1
3-1
3-1
34
34

e e e e e e e e e e e e e e
. .
i i
i
it e e e
.
.
ittt i i e e
o
. .
it e it e i et o
. . . o it et et i
e e
. . .
i it i
et e
e
.
i i it
i
it e e e
. . . .. .. .. .. ... ...

4-1
4-1
4-1
4-2
4-3
4-5
4-6
4-8

e e e e e e e e e e e
e e e e
i e e e s
e e e e e e s
.. .. . . .
v v v
.. .. .. ... . . oo
e e e e e e e e e e e e e e e e e e
e

5-1
5-1
5-1
5-1
5-1

e e e e e e e

e e e e
e e e e e
e e e
e
e e e e e
.. ...
e e e e e
e

2-4
2-4

ILLUSTRATIONS

Figure No.

Title

1-1

Simplified Block Diagram — 861-A-B,-C-F

1-2

Simplified Block Diagram — 861-D,-E

2-1

Connector Wiring

Page
. ... .. ... ... ... ...

. . . . . ... . ... .. ...

.....

1-2

e e e e e e

2-3

. . . . . . . . . . .
i
e
e e e e
e
e
. . . . .. . .. ... ... ... ...,

3-2

. . ... ... ..... e

2-2

Signal Bus Connector

3-1

Type 861-A,-B,-C Power Controller Panels

e e e e e e e e e e e e

2-4

3-2

Type 861-D,-E Power Controller Panels

3-3

Type 861-F Power Controller Panel

. . . . . ... ... ... .. ... .. ......

3-3

. . . .. ... .. .. ... ... . ... ...

4-1

861-A Simplified Circuit Schematic Diagram

4-2

861-B Simplified Circuit Schematic Diagram

...

4-3

4-3
4-4

861-C Simplified Circuit Schematic Diagram . . . . . .. ... ... ... ... ... ...
861-D Simplified Circuit Schematic Diagram
. . ... .. ... ... ... ... .....

4-5

861-E Simplified Circuit Schematic Diagram

. . . . ... ... .. .. ... .. ... ...

4-6

861-F Simplified Circuit Schematic Diagram

. .. .. ... .. ... .. ..........

4-7

5-1

861-A,-B,-C,-F Power Controller Component Identification

5-2

861-D Power Controller Component Identification

. . . . . ... ... ... ... .......

. . . .. ... ... ... ...

...

. .. ... ... .. ... ...

. . ... ... .. e

e e e e e e

4-2

4-4

5-2

. . . . . .. .. .. ... ... .....

5-3

Troubleshooting Flow Diagram — 861-A,-B,-C-F

5-4

Troubleshooting Flow Diagram — 861-D

. . . .. . ... ... ... ... .........

5-4

5-5

Troubleshooting Flow Diagram —861-E

. . . . . . . .. . . ... ... ... .......

5-5

TABLES

Table No.

Title

2-1

Input Power Cables

2-2

Input Power Cable Connectors

. . . . . . . . .

Page
e

. . . . . . . . .

\Y%

e e e e e e e e e

i i i i i i i e

e e e e

2-2

e e e e e e e e e

2-2

ATTETEEGER

861-A,-B,-C,-D,-E,-F POWER CONTROLLER

6496-5

861-A.,-B,-C,-F Power Controller

7570-1

-861-D,-E Power Controller

B B Qi

CHAPTER 1

INTRODUCTION

Figures 1-1 and 1-2 are simplified block diagrams
of the 861 Power Controllers. Four basic functions

This manual provides information for installing, operating, and maintaining the 861-A, 861-B, 861-C,
861-D, 861-E, and 861-F Power Controllers, designed and manufactured by Digital Equipment
-

are performed:

Corporation.

1.1

GENERAL DESCRIPTION

The 861 Power Controllers provide a means for controlling and distributing power to data processing

All versions are contained on panels intended for
mounting in racks or cabinets that accept standard
19-inch panels. Each power controller requires 53/16 inches of vertical mounting space. The 861-A,- B,-C,-F extends 8-1/4 inches into the mounting
rack or cabinet and the 861-D,-E extends 11 inches

Filtering of primary power to controlled

1.2

Automatic removal of primary power
from controlled devices in case of overload or overtemperature conditions.

SPECIFICATIONS

The following specifications are included here for
reference purposes only and are subject to change

The following versions are available to provide for
a variety of input power configurations:

without notice.

Hertz

Phase

861-A | 90-135 | 47-63

Two (120° or 180° displaced)

180-270 | 47-63

Single

| 90-135

| 47-63

Single

861-D

| 90-132

| 47-63

Three (120° displaced)

861-E

180-264 | 47-63

Three (120° displaced)

861-B

861-C

861-F

90-135

of primary

devices.

into the mounting rack or cabinet.

Voltage

Convenient distribution
power to controlled devices.

equipment.

Version

Control of large amounts of power by
control signals of small power content.

47-63

Single

1-1

TITE

UN
SWITCHED
OUTLETS

INPUT

LINE

PILOT

CIRCUIT

BREAKER

LAMPS

FILTER

SPIKE

SUPPRESSION
CIRCUIT

RELAY
REMOTE
OFF
LOCAL
SWITCH

«—— POWER

SWITCHED
OUTLETS

REQUEST

PILOT

CONTROLlke— EMERGENCY SHUTDOWN
CIRCUIT

«—— COMMON

THERMAL

SWITCH

CP-0354

Figure 1-1

Simplified Block Diagram - 861-A,-B,-C,-F

PILOT

LIGHTS

15'SJT

CSRD*

INPUT

TWIST, PLUG

FOUR

LINE

FILTER

SWLIJ1NC-HED
OUTLETS

CIRCUIT

BREAKER

CEMOTE

CONTACTOR

OFF
LOCAL
SWITCH

SPIKE

SUPPRESSION
CIRCUIT

l«— POWER

TEN

Sgfilfigfig

REQUEST

PILOT

CONTROLle— EMERGENCY SHUTDOWN
CIRCUIT

le— COMMON

THERMAL

SWITCH

*NOTE
Not supplied
with 861-E

CP-I735

Figure 1-2

Simplified Block Diagram - 861-D,-E

LT I
T

1.2.1

Frequency

Mechanical And Environmental

47 Hz - 63 Hz

Dimensions

861-A,-B,-C,-F: 5 in. h x 19-1/8 in. w x 8 1n.
d (12.7 cm h x 48.5 cm w x 20.3 cm d)

Current

861-A: 16A per pole; 861-B: 16A per
pole; 861-C: 24A per pole; 861-D: 24A
per pole; 861-E: 15A per pole; 861-F:

861-D,-E,: 5 in. h x 19-1/8 in. w x 11 in. d
(12.7cm h x 48.5cm w x 27.9 cm d)

[2A per pole.
Power Requirements

Weight

Full Load

861-A,-B,-C,-F: 10 Ib (4.54 kg) (approx)

861-A: 3830 VA; 861-B: 3830 VA; 861C: 2870 VA; 861-D: 8640 VA; 861-E:

861-D,-E: 27 1b (12.26 kg) (approx)

10,800 VA; 861-F: 1435 VA

Cooling Method

Convection

No Load

861-A,-B,-C,-D,-E,-F: 10 VA

Mounting

Rack (standard 19 in.)

Inrush Current Capability
240 A peak, 1 cycle

Ambient Temperature

Leakage Current

Operating

861-D: 1.75 mA max. 861-E: 3.5 mA makx.

861-A,-B,-C,-F: 0° to +60° C

Input Overvoltage Transient

861-D,-E: 0° to +70° C

180/360 V, 1 sec (power controller alone)

Storage

Activate Time

-40° to 71° C

20 ms (from switch closing to power out)

Relative Humidity

Deactivate Time

95% max (no condensation)

10 ms (from switch opening to power out)

Altitude

Input Breaker

861-A,-B,-C,-F: 10,000 ft (max)

861-A.,-B,-C: 20 A delayed action, manual re-

861-D,-E: 8000 ft (max)
1.2.2

set, magnetic

861-D: 30 A delayed action, manual reset,

Electrical

magnetic

861-E:

Input Power

15 A delayed action, manual reset,

magnetic

Voltage

861-F:

861-A.,-C,-F: 90 Vac - 135 Vac; 861-B:
180 Vac - 270 Vac; 861-D: 90 Vac - 132

10 A delayed action, manual reset,

magnetic

Vac; 861-E: 180 Vac - 264 Vac
Thermoswitch

Phase

861-A: Two (120° or 180° displaced);
861-B,-C,-F: Single; 861-D,-E: Three

Opens at 160°F, automatically resets at 120°
F, 49° C (exposed to ambient air external to

(120° displaced)

controller)

1-3

R
TR

Capacitance

Input Power Connector

861-A: 4-prong twist plug, NEMA* L14-20P;
861-B: 3-prong twist plug NEMA L6-20P;
861-C: 3-prong twist plug NEMA L5-30P;
861-D: 5-prong twist plug, NEMA L21-30P;
861-E: pressure fit terminal block;
861-F: 3-prong standard plug NEMA L5-15P.

200 pF (max)

Output (861-A,-B,-C,-F)
Outlets (power)

Twelve (8 switched, 4 unswitched)
Outlet Current Ratings

861-A: 12 A per outlet, 16 A per branch

Hipot

2.1

kVdc for 60 sec (input and output to

circuit, 32 A total; 861-B: 12 A per outlet, 16 A total; 861-C: 12 A per outlet,

chassis).

16 A per branch circuit, 24 A total; 8618 A per branch cir-

F: 6 A per outlet,

Remote Switching Control Connectors

3 each: Female, AMP 1-480304-0 (DEC-12
09350-03) with AMP 61117-4 (DEC-12-09379)
pins or equivalent that mate with AMP 1480305-0 (DEC-12-09351) with AMP 61118-4
(DEC-12-09378) pins or equivalent

cuit, 12 A total.

Outlet Inrush Current
861-A: 240 A peak per branch circuit (1
cycle), 480 A peak total (1 cycle); 861-B:
240 A peak total (1 cycle); 861-C: 240 A

peak per branch circuit (1 cycle), 360 A

Input Signal Current Levels

861-A,-B,-C,-F: 0.5 mA (min), 10 mA (max);
861-D,-E:
0.5 mA (min), 40 mA (max) load
worst case to each bus signal line when con-

peak total (1 cycle); 861-F: 120 A peak
per branch circuit (1 cycle), 180 A peak
total (1 cycle).

nected to pin 3.
Output (861-D,-E)
Outlets (power)

Input Signal Voltage Levels

861-A,-B,-C,-F: 3.0 V max = low; +35 V min

Fourteen (10 switched, 4 unswitched)

= high (open circuit = high); 861-D,-E: +3.0
V max = low; +32 V min = high. Worst case

Outlet Current Ratings

861-D: 15 A per outlet, 24 A per phase,

to each bus signal line in relation to pin 3.

72 A total; 861-E: 12 A per outlet, 15 A
per phase, 45 A total.
Bus Signal Line Overload Capability
125 Vac rms @ 60 Hz, 13 kQ impedance in relation

for

two

seconds

with

Outlet Inrush Current

240 A peak per branch circuit (1 cycle)

damage

All provisions of Underwriters Laboratories Specification UL-478 have been met in the design and
Power Control Impedance

Inductive (diode suppressed)

*National Electrical Manufacturer’s Association

manufacture of the 861-A,

861-B,

861-E and 861-F Power Controllers.

861-C,

861-D,

CHAPTER 2
INSTALLATION

These cable assemblies are described in the follow-

2.1 SITE CONSIDERATIONS
The dimensions of the 861-A,-B,-C, and -F Power

ing paragraphs.

Controllers are identical. Each is contained on a
19-inch panel intended for mounting on a rack or
in a cabinet that accepts standard 19-inch panels.
Each power controller requires 5-1/4 inches of vertical mounting space and extends approximately 3

2.2.1

inches into the mounting rack or cabinet. For convenience, the power controller should be mounted

as close as feasible to the units it controls.

EMI/RFI protection.)

The dimensions of the 861-D and -E Power Controllers are identical. Each is contained on a 19inch panel intended for mounting on a rack or in a
cabinet that accepts standard 19-inch panels. Each

The power cable connector types provided also
differ depending upon which 861 version is being installed. Table 2-2 lists the plug and receptacle types

power controller requires 5-1/4 inches of vertical

mounting space and extends approximately 11
inches into the mounting rack or cabinet. For convenience, the power controller should be mounted
as close as feasible to the units it controls.

with NEMA and DEC designations. Figure 2-1
shows the power connector outlines and provides
color coding information.

Ambient temperature at the installation site should
not exceed +60°C: for the 861-A,-B,-C,-F or +70°
C for the 861-D,-E; relative humidity should remain below 95 percent, with no condensation. For
other environmental particulars, refer to Paragraph

The input power cable connects to the 4-terminal
block at the side of the line filter. In 861-A installations, the following connections must be made:
a.

1.2.

2.2

Input Power

The type of input power cable depends on which
version of the power controller is being installed.
Table 2-1 describes the input power cables. Cables
supplied are 15 feet in length and are composed of
insulated stranded conductors. (Cables with a
grounded shield braid are recommended for

Green — N (Earth Ground)
Black — C (Phase 2)
White - B (Neutral)

CABLES

Red - A (Phase I)

Each power controller requires the following cables:
a.

Input Power (provided with 861-A,-B,-

C,-D,-F only)

Remote Switching Control, DEC No.
70-08288, 70-10695, or equivalent (not

a.
Qe
o

provided)

861-B

installations the following connections

must be made:

Output Power (provided with controlled
units)

2-1

Green — N (Earth Ground)
White — B (Phase or Neutral)
Black — C (Phase or Neutral)
No Connection - A

i
4
R

Table 2-1
Input Power Cables

Controller

Conductors

Size

Coding

861-A
861-B
861-C

4
3
3

#12 AWG | Green, black, white, red
#14 AWG | Green, black, white
#12 AWG | Green, black, white

861-D
861-E

5
5

#10 AWG | Green/yellow, black, white, red, orange
#14 AWG | Green/Yellow, black, black, brown, blue (not provided)
(Shielded)

861-F

#14 AWG | Green, black, white

Table 2-2
Input Power Cable Connectors

861-A

4-Prong Twist Plug
4-Prong Twist Receptacle

861-B

861-C

861-D

3-Prong Twist Plug

NEMA No.

DEC No.

L14-20P
L14-20R

12-11046

12-11045

L6-20P

12-11192

3-Prong Twist Receptacle

L6-20R

12-11191

3-Prong Twist Plug

L5-30P

12-11193

3-Prong Twist Receptacle

L5-30R

12-11194

5-Prong Twist Plug

L21-30P

12-12314

5-Prong Twist Receptacle

L21-30R

12-12315

861-E

(Not provided)

- 861-F

3-Prong Plug

L5-15P

90-08938

3-Prong Receptacle

L5-15R

12-05351

ATHEE

RECEPTACLE

PLUG

PHASE 1

GREEN

RED

()

EARTH
GROUND

WHITE

]

PHASE 2

WHITE

GREEN

NEUTRAL

\\\ NEMA L14 - 20R
U/W 861-A

BLACK

NEMA L14-20P
U/wW 861-A

PHASE OR
NEUTRAL

GREEN

_{E

EARTH

(NEUTRAL
PREFERRED)

WHITE

PHASE OR

BLACK

GREEN

NEUTRAL

GROUND

\ NEMA L6-20R

NEMA L6-20P

U/wW 861-8B

GREEN

EARTH

GROUND

Uu/w 861-8B

WHITE

'(5 %

PHASE

BLACK

C§

NEUTRAL

EARTH
GROUND

GREEN

NEMA L5-30R

NEMA L5-30P

U/W 861-C

U/w 861-C

BLACK

GREEN/YELLOW

NEUTRAL

WHITE
$3

NEMA L21-30R
U/W 861-D

GREEN

BLACK

ORANGE

NEMA L21-30F
U/W 861-D

GREEN

WHITE

NEMA L5-15R
U/W

861-F

WHITE

;

BLACK

\\\—/<< NEMA L5-15P
U/W 861-F

11-3202

Figure 2-1

Connector Wiring

In 861-C.-F installations, the following connections
must be made:

Green — N (Earth Ground)

White - A (Neutral)

Black — B (Phase)

POWER REQUEST
EMERGENCY SHUTDOWN
SIGNAL

RETURN

In 861-D installations, the following connections
must be made:
CP-0355

Black — (Phase 1)

a o

Green/yellow — N (Earth Ground)
White - (Neutral)

Orange - (Phase 3)

Figure 2-2

Red - (Phase 2)

Signal Bus Connector

switched, 4 unswitched). Power cables must be terminated with standard 3-prong male connectors
(NEMA 5-15P for the 861-A,-C,-F and NEMA 6ISP for 861-B) to mate with the female connectors
(NEMA 5-15R for the 861-A,-C,-F and NEMA 6-

NOTE

The 861-E Power Controller is not supplied with an

ac power cord and connector. It is shipped with a

[5R for 861-B) on the panel.

strain relief installed. Local electrical codes should be
referenced for the size and type of power cord and

Power for the 861-D,-E is provided to controlled
units from the 14 convenience outlets (10 switched,
4 unswitched). Power cables must be terminated
with standard 3-prong male connectors (NEMAS[5P or 5-20P for the 861-D and NEMA 6-15P for
the 861-E) to mate with the female connectors
(NEMA 5-15R or 5-20R for the 861-D and NEMA
6-15R for the 861-E) on the panel.

connector used.

2.2.2

Remote Switching Control
Three female bus connectors, wired in parallel, are

provided on the front panel for accepting and re-

routing the Remote Switching Control Bus. Each i1s
an AMP Mate-N-Lok type AMP 1-480304-0 (DEC-

12-0-350-3) with AMP G117-4 (DEC-12-09379) pins
or equivalent.

2.3

GROUNDING

A good return ground is essential to proper power
controller operation. A secure electrical connection
must exist between the controller and the frame of

Connections between units are effected with from
one to three cable assemblies of 3-conductor stranded #22 AWG cable terminated at each end with
male connectors. These are AMP 1-480305 (DEC12-09351) with AMP 61118-4 (DEC-12-09378) pins

the associated rack or cabinet. To accomplish this,
(861-A,-B,-C,-F) use a 10-32 nut with serrated

or equivalent. Cable assembly details are shown on

washer and a 10-32 bolt with serrated washer in at
least one of the four mounting holes. For the 861-

drawing DEC-70-08288. Color coding is as follows:
a.

Pin I - Red

D.-E, use a serrated washer and a 10-32 bolt with
serrated washer in a 10-32 press nut on the rear of

Pin 2 - Black

the controller.

Pin 3 - Green

2.4

INITIAL OPERATION
Before applying primary power to the power con-

Remote Switching Control Bus lines connect the
Signal Return, Power Request, and Emergency
vices to the power controller in systems employing

troller, determine that the power at the mains is of
the correct value for the particular 861 version
being installed and that all cables are connected

compatible automatic control features. These lines

correctly.

Shutdown lines from the processor and system de-

are low for assertion. Figure 2-2 shows one female
NOTE

connector viewed from the front.

If the controller is being installed in a system where
Power for the 861-A,-B,-C,-F is provided to con-

the Emergency Shutdown and Power Request lines
are not in use, the LOCAL/OFF/REMOTE switch

trolled

must be in the LOCAL position.

Qutput Power

units from the

12 convenience outlets (8

2.2.3

In systems where the Emergency Shutdown and
Power Request lines (or their equivalents) are to be
used, provisions must exist for connecting pin 1 to
pin 3 when normal operation is desired (power is
supplied to the controlled devices through the
switched outlets). Provision must also exist for connecting pin 3 to pin 2 if an Emergency Shutdown
feature is to be implemented.

Once it has been determined that correct power ex-

ists at the mains and that all cabling is correct, and
before connecting any devices to the power outlets,
connect the controller power plug to the appropriate receptacle. All pilot lamps on the panel should
light. The circuit breaker(s) on the panel should be
thrown to the ON position and the LOCAL/OFF/REMOTE switch to the LOCAL position. Measure the voltage at the switched and

unswitched outlets. If the measured values are cor-

rect for the power controller in use, the power controller should be shut down, the loads connected to
the switched and unswitched outlets*, and the circuit
breaker(s) thrown ON again. The system should
now operate. If the circuit breaker trips, or other
abnormality exists, refer to the maintenance information in Chapter 3.

If the Emergency Shutdown feature is in use, check
that the power controller responds properly to shutdown requests from each external device.

Also, if required, the operation of the thermally-activated overtemperature switch can be checked by
holding a match in proximity to the sensing element and observing that the switched outlets are
disabled. The thermal switch should reset automat-

ically after a brief period, once the flame is
removed.

* oads should be balanced between circuits.

TEY

ATHETR

CHAPTER 3
OPERATION

The following are the outlet current ratings:

3.1 CONTROLS AND INDICATORS
Figure 3-1 shows the front panels for the 861-A,
861-B and 861-C Power Controllers. Each version
has two pilot lamps, a circuit breaker, a 3-position

Version

toggle switch, and several power outlets. Their functions are discussed in the following paragraphs.

681-A
681-B
861-C
861-D
861-E
861-F

Figure 3-2 shows the front and back panels for the
861-D and 861-E Power Controllers. Each version
has three pilot lamps, a main circuit breaker, a 3position toggle switch, and several power outlets. In
addition, the 861-D has six branch circuit breakers.
Their functions are discussed in the following

Per Outlet | Per Branch/Phase
12A
12A
12A
15A
12A
6A

16A
16A
16A
24A
15A
8A

Total
32A
16A
24A
T2A
45A
12A

paragraphs.

Figure 3-3 shows the front panel for the 861-F
Power Controller. Controls, indicators and outlets

3.1.3

The LOCAL/OFF/REMOTE switch provides the
Remote Switching Bus with the means to control
the power to the switched outlets. When the power
controller is energized and the switch 1s in the OFF
position, the switched outlets are disabled. When in

are the same as for the 861-C.
3.1.1

Pilot Lamps

In all 861 Power Controller versions, all pilot lamps
are lighted whenever the controller input power
cable is connected to the live mains, regardless of
the position of the power controller circuit breaker
or LOCAL/OFF/REMOTE switch.
3.1.2

LOCAL/OFF/REMOTE Switch

the REMOTE position and connected to a bus

where Power Request and Emergency Shutdown
are in use (or a means of effecting connection between pin 3 and pins 1 or 2 exists), the switched

outlets are enabled or disabled in accordance with

conditions on the bus. When in the LOCAL position, the switched outlets are enabled only when the
Emergency Shutdown signal is not asserted.

Circuit Breaker

Circuit breaker CBI, when ON, provides power to
the unswitched outlets, and to the switched outlets
when the LOCAL/OFF/REMOTE switch is in the
LOCAL nosition (or in the REMOTE position and
a connection exists between pins 1 and 3 of a Re-

3.1.4

Remote Switching Control Bus Connectors
The three female Signal Bus connectors, adjacent to
the LOCAL/OFF/REMOTE switch, are wired in
parallel. These connectors provide a means of
daisy-chaining the Remote Switching Control Bus
between the controller and system devices.

mote Switching Control Bus connector*). The circuit
breaker opens automatically when an overload condition exists at a power outlet or within the power

controller.

*A connection between pins 2 and 3 of the Remote Switching
Control Bus disables the switched outlets, regardless of the position of the LOCAL/OFF/REMOTE switch.

3-1

[

CIRCUIT

TWO

SWITCHED
CIRCUIT
TWO

CIRCUIT

ONE

]

CIRCUIT
]

1 8

UNSWITCHED

__ LOCAL
REMOTE
|
l

CONTROL_B6{A
POWER CONTROL,
88/
POWER
3 POLE 4 WIRE 16A

50-60HZ

)

IOI

CIRCUIT

| q

CP-0376

REMOTE

POWER CONTROL 8618

SWITCHED

[

INPUT 240V 50-60 HZ

2 POLE 3 WIRE 16A

]

®
]

~OFF

]

UNSWITCHED

LOCAL
~ON

]

(]

CP-0375

CIRCOTT

CIRCUTT

S AT T

I
]

o
®

CTRCUTT
]

|®
|@8§

CTRCUT

| g

—

QD@..
CP-0374

861-C

Figure 3-1

Type 861-A,-B,-C Power Controller Panels

3-2

TTHEEE

PHASE

L,
3

r"swncueow

-D
ae1
CONTROL
POWER {20V
] INPUT
50/60
H

REMOTE] I..OCAL

@) Senll
—
-

®|®

ON .

| &

CIRCUIT ¢

FE‘D

L S |3 PHASE 5 WIRE 24A/PHASE
ON

— a—

——

CIRCUIT 4

@
N

@15 AMPS AT 120 VOLTS @
MAXIMUM PER CIRCUIT

CIRCUIT 2

@) GEENE) ()
CIRCUIT 2

UNSWITCHED

p———— SWITCHED ————jr-swchueoj

@ @ ©@
MAIN POWER

©)

PHASE 1

PHASE 2

PHASE 1-CIRCUIT{

861-D (Front Panel)

PHASE

()
Cal)

CIRCUIT 2 e

CIRCUIT 2-——J CIRCUIT

L_cmcuna—JA— CIRCUIT 1

861-D (Back Panel)
£

OFF

REMOTE |
ON

PHASE | -CIRCUIT {

UNSWITCHED

@ (
O

LOCAL
ON

”’

MAIN

POWER

MAXIMUM CURRENT AT 240 VOLTS

ALL OUTLETS
ON REAR OF
THIS UNIT
ARE SWITCHED

12 AMPS/OUTLET- 18 AMPS/PHASE

113

CONTROL 861-E

INPUT 240 50/60 HZ
3 PHASE 5 WIRE 15A/PHASE

POWER

N—

LD,

( Front Panel)
861-F

PHASE 3 =y

PHASE

GO
L—CIRCUIT 2 — “ CIRCUIT 1

CIRCUIT 2 —~ %

CIRCUIT

CIRCUIT 2 —

CP-1730

( Back Panel)
I-E

Figure 3-2

Type 861-D,-E Power Controller Panels

3-3

C‘RCU|T

i ('D) (W) ()
OO

LOCAL
REMOTE
OlN
OIN FIF

2 POLE 3 WIRE 12A

UNSWITCHED
CTRCUTT
CIRCUTT

{eee

CIRCUIT

Heee

CIRCUIT

{eee]]

SWITCHED

CIRCUIT

@@ )

CcrP-1731

Figure 3-3

Type 861-F Power Controller Panel

Two groups of power outlets are provided on the

LOCAL/OFF/REMOTE switch in the
REMOTE or LOCAL position and a

panel. The group containing eight (861-A,-B,-C,-F)

connection exists between the lines asso-

or ten (861-D,-E) receptacles is the switched group.

ciated with pins 3 and 2 of the Remote

Under normal conditions, power is available at
these outlets when the LOCAL/OFF/REMOTE
switch is in the LOCAL position, or when in the

gency Shutdown signal asserted).

3.1.5

Power Outlets

Switching Control Bus connectors (Emer-

REMOTE position and a connection exists between

Overtemperature switch closed.

pins 1 and 3 of the Remote Switching Control Bus
connector. Power is removed from these outlets by

The group containing four power outlets is not con-

any of the following:

trolled

(or branch circuit breakers OFF if 861-

by the Remote Switching Control Bus.
Power is available at these outlets when the main
circuit breaker is closed and the power controller is
connected to the live mains. (861-D: branch cir-

D.)

cuit breaker also closed.)

Main circuit breaker in OFF position,

LOCAL/OFF/REMOTE switch in the
OFF position.

3.1.6

LOCAL/OFF/REMOTE switch in the
REMOTE position and no connection
exists between the lines associated with

A thermally-activated switch is provided to disable
the controlled outlets in the event of an overtemperature condition at the power controller. The
switch opens at 160° F and resets automatically
when the ambient temperature at the power con-

pins

and 3 of the Remote Switching

Overtemperature Switch

troller drops below 120° F.

Control Bus Connectors.

3-4

CHAPTER 4

THEORY OF OPERATION

4.1

with K1 is energized by 90-135 Vac from the out-

GENERAL

Although the six versions of the 861 Power Controller are quite similar, they are discussed separately in the following paragraphs to maintain
clarity. The pilot control board is identical in each

put of CB1 if a relay on the pilot control board is
closed (see Paragraph 4.8 for a description of the pi-

version and is therefore described once.

When K1 is closed, 90-135 Vac is applied across
outlets P3, P4, P5, and P6. The two 0.1 uF capacitors (C1), connected across the lines at the relay, reduce the amplitude of voltage spikes at the output
of the controller when switching inductive loads,
thereby preventing interference to nearby electronic

4.2

lot control board).

TYPE 861-A CIRCUIT DESCRIPTION

Figure 4-1 is an 861-A simplified circuit schematic.
The 861-A is the 90 - 135 Vac, 47 - 63 Hz, twophase version of the power controller.

data processing equipment.

Power is applied to the terminal block mounted on
the power line filter. This filter contains 0.1 uF capacitors, which connect between neutral and each
of the two phase lines and ground. Also contained
in the filter are four chokes, connected in series

4.3 TYPE 861-B CIRCUIT DESCRIPTION
Figure 4-2 is a simplified circuit schematic of the
861-B, the 180-270 Vac, 47-63 Hz, single-phase version of the power controller.

with each of the three lines and ground. The capacitors provide low impedance paths to ground for
high frequency line components. The chokes present a high impedance to these components. If 90 -

Power is applied to the terminal block mounted on
the power line filter. This filter contains 0.1 uF ca-

pacitors which connect between each side of the
180-270 Vac line and ground. Also contained in the
filter are three chokes connected in series with each
of the two lines and ground. The capacitors provide
low impedance paths to ground for high frequency

135 Vac exists between phase 2 and neutral, I1

lights. Similarly, if 90 — 135 Vac is present between
phase 1 and neutral, 12 lights. All three lines are
connected to 20 A elements at the circuit breaker,
CB1. All loads connected to the power controller
(both switched and unswitched) are controlled by

line components. The chokes present a high impedance to these components. If 180-270 Vac is present across the lines at the output of the line filter,
both Il and I2 (connected in series) light. Each side
of the line connects to a 20 A element of circuit
breaker CB1. All loads connected to the power controller (both switched and unswitched) are controlled by CBI1. If the current through either line
exceeds 20 A, CBI trips, removing power from the
load. Power outlets P2 and Pl connect across the
output of CBI1. These outlets are energized

CBI.

If the current through any of the three lines exceeds
20 A, CBI1 trips, removing power from the loads.
Power outlets P1 and P2 connect across the circuit
breaker output. These outlets are energized (90-135
Vac) whenever the circuit breaker is closed. Each
outlet line from CBI1 is connected to a normally
open contact on relay K1. The field coil associated

4-1

|
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i

T AWF TR AuF TR ARF

20n

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.

—— =

e e

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L__

TIR B B
11

—

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{

oe!

L14-20P

AC INPUT

Y
L~

ROL |
BOARD
l_< ) [PiLoT CONT
'

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j
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LOCSL °

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7
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U2>

ul1

w2l

3[1

3
CP-0356

Figure 4-1

(180-270

Vac)

whenever

the

861-A Simplified Circuit Schematic Diagram

circuit

breaker

4.4 TYPE 861-C CIRCUIT DESCRIPTION
Figure 4-3 is a simplified circuit schematic of the
861-C, the 90-135 Vac, 47-63 Hz, single-phase ver-

closed. Each output line: from CBI1 connects to a

normally open contact on relay K1. The field coil
associated with K1 is energized by 180-270 Vac
from the output of CBI if a relay on the pilot con-

sion of the power controller.

Power is applied to the terminal block mounted on
the power line filter. This filter contains 0.1 uF capacitors which connect between each line and
ground. Also contained in the filter are three

trol board (Paragraph 4.8) is closed. When K1 is
closed, 180-270 Vac is applied across outlets P3,
P4, P5, and P6. The 0.1 uF capacitor (Cl), connected across the lines at the relay, reduces the amplitude of wvoltage spikes at the output of the
control when switching inductive loads, thereby preventing interference to nearby electronic data pro

chokes, connected in series with each of the two

lines and ground. The capacitors provide low 1mpedance paths to ground for high frequency line
components. The chokes present a high impedance

cessing equipment.

4-2

X g]

i
f

|
;
|

AC INPUT

L6-20P

.
YY)

_____

(@)

!
|

T
v

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qab d

||
I |

AN I N
I

|
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~
e o o ee ] =

J
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T AuF ~.AunF :

i
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L
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11
1

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r- K1 1 r

r CcBi -'

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L 26———|

—

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—<4

¥ 03

SEMOTEI

LOCéh

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l—>2\r

Jalt1

3
cP-0358

Figure 4-2

861-B Simplified Circuit Schematic Diagram

Each output line from CBI connects to a normally
open contact on relay KI. The field coil associated
with K1 is energized by 90-135 Vac from the output of CB1 if a relay on the pilot control board
(Paragraph 4.8) is closed. When K1 is closed,
90-135 Vac is applied across outlets P3, P4, P53,
and P6. The two 0.1 uF capacitors, connected
across the lines at the relay, reduce the amplitude
of voltage spikes when switching inductive loads,
thereby preventing interference to nearby electronic

to these components. If 90-135 Vac exists across
the output of the line filter, pilot lamps I2 and Il
(connected in parallel) light. The neutral line 1s connected to a 30 A element at circuit breaker CBI.
The phase line is branched; each resulting line connects to a separate 20 A element at CBI1. All loads
connected to the power controller (both switched
and unswitched) are controlled by CBI1. If the current through the upper (shared) line exceeds 30 A,
or if the current in either of the remaining lines exceeds 20 A, the circuit breaker trips, removing
power from the load. Power outlets P1 and P2 connect across the output of CBI. These outlets are
energized (95-130 Vac) whenever the circuit breaker

data processing equipment.

4.5 TYPE 861-D CIRCUIT DESCRIPTION
Figure 4-4 is an 861-D simplified circuit schematic.
The 861-D is a 90-132 Vac, 47-63 Hz, three-phase

is closed.

Power Controller.

4-3

F1q

-|
|

{

!
1

AC INPUT
L5-30P

|
f

[

|
|

208

;
|

—| r-

| |

|
I

||
||

|
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——
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&
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4(!
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Bl

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'

L - -

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20A

= AuF = AuF |

oa0a

.
AAA
—

[

r CB1 —|

'
|

ON OFFOON

REMOTE

;

\1\
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V7

ul1

B3l

3
CP-0357

Figure 4-3

861-C Simplified Circuit Schematic Diagram

Power is applied to the terminal block mounted on

All three lines are connected to 30 A elements at

the power line filter via a 15-foot line cord. This fil-

the circuit breaker CB1. All loads connected to the

ter contains

power controller (both switched and

.03 uF capacitors which connect be-

tween neutral and each of the three phase lines and

ground.

Also

contained

the

filter

are

unswitched)

‘are controlled by individual 20 A circuit breakersA.

nine

chokes, two connected in series with each of the

If the current through any of the lines exceeds 20

four lines and one to ground. The capacitors pro-

vide low impedance paths to ground for high fre-

power from the loads. Phase 1, circuit 1 outlets con-

the

respective

circuit

breaker trips,

removing

quency line components. The chokes present a high

nect across the main circuit breaker output. These

impedance to these components. If 90-132 Vac ex-

outlets are energized (90-132 Vac) whenever the cir-

cuit breaker is closed. All outlet lines from CBI1 are

90-132 Vac is present between phase 2 and neutral,

ists

connected to a normally open contact on contactor

between

lLights.

phase

Similarly,

and

neutral,

lights.

K 1. The field coil associated with K1 is energized

if 90-132 Vac is present be-

tween phase 3 and neutral, I3 lights.

by 156-229 Vac from the output of CBI if a relay

4-4

UNSWITCHED
OUTLETS

CK 2

CK 1

INPUT

NEMEor @
02

yo\

L__—///,_t_xvvv

GND

<:E)

[E:(?_r\fiA-C-To?

B 1 (g, (,204

TLINE FILTER —_i

Qfi) .

2 | ~

_J_}:Z

T | ourcers

l-- P

l- ————— --l

!—T- _r
|

fcon |

I I
_r

,6
¢ (2oa(]é (20a
b

‘ilili
@3

CK 1

PILOT

CONTROL

__(2 '

—3

‘

BOARD

K{ + 1

':}——_- |

]

1T T L1

2
CK

( (§,2°A( (1,20“( (fi.ZOA

R
S

j— —r‘

-0 O

CK 1

CK
2

)

I
l

/J7 l—» D oD | CEe GRS CRD -j- ——— GEmm s -J
> 1>

PN
3

N
2

PaN
1
CP-1732

Figure 4-4

861-D Simplified Circuit Schematic Diagram

(K 1*) on the pilot control board is closed (see Para-

Power is applied to the terminal block mounted on

graph 4.8 for a description of the pilot control

the power line filter. This filter contains .03 uF ca-

board).

TYPE 861-E CIRCUIT DESCRIPTION

pacitors which connect between neutral and each of
the 3-phase, 180-264 Vac line and ground. Also
contained in the filter are nine chokes, two connected in series with each of the four lines and one
to ground. The capacitors provide low 1mpedance
paths to ground for high frequency line components. The chokes present a high impedance to
these components. If 180- 264 Vac i1s present across
each line at the output of the line filter, I1, 12 and
I3 light. Each side of the line connects to a 15 A element of circuit breaker CBI. All loads connected to
the power controller (both switched and unswitched) are controlled by CBI. If the current

Figure 4-5 is a simplified circuit schematic of the

through either line exceeds 15 A, CBI trips, remov-

When K1 is closed, 90-132 Vac is applied across

Phase 1, circuit 2, Phase 2, circuits 1 and 2, and
Phase 3, circuits 1 and 2. The three 0.1 uF capacitors (Cl1 and C2), connected across the lines at the
relay, reduce the amplitude of voltage spikes at the

output of the controller when switching inductive
loads,

thereby

preventing

interference

nearby

electronic data processing equipment.

4.6

861-E, the 180-264 Vac, 47-63 Hz, three-phase ver-

ing power from the load. Phase 1, circuit 1 con-

sion of the Power Controller.

nects across the output of CBIl. These outlets are
4-5

Cbi o

UNSWITCHED
OUTLETS

@1
CK2

o1
CK 1

FLINE FILTER

-'-]

@2 ___!_rm
03

l
_ ___I__m‘rv\

——1—JY“fi

e 1

ri§fi}56hfi3

Jlll'— i

]

|con

{ T

K1 *3

—2
_____<3

PILOT CONTROL BOARD

¥ D3
LOCAL

SWITCHED
OUTLETS

= b-

Tc2 10

—

‘I}—_—i __01_]_

TTT |
ono| 4—f~n T

T T 111

CK 1

2
CK

———-_—J

— 1

02
CK2

02
CK1

—
S B —_—

) N

ONj

OFF fON

)1\
7
7

CP-1733

Figure 4-5

861-E Simplified Circuit Schematic Diagram

4.7 TYPE 861-F CIRCUIT DESCRIPTION
Figure 4-6 is a simplified circuit schematic of the
861-F, a 90-135 Vac, 47-63 Hz, single-phase version of the Power Controller.

energized (180-264 Vac) whenever the circuit
breaker is closed. Each output line from CBI connects to a normally open contact on contactor K1.
The field coil associated with K1 is energized by
180-264 Vac from the output of CBI1 if a relay
(K 1*) on the pilot control board (Paragraph 4.8) is

Power is applied to the terminal block mounted on
the power line filter. This filter contains 0.1 uF ca-

closed. When K1 is closed, 180-264 Vac is applied
across outlets Phase 1, circuit 2, Phase 2, circuits 1

pacitors
ground.

and 2, and Phase 3, circuit |1 and 2. The 0.1 uF ca-

which connect between each line and
Also contained in the filter are three

chokes, connected in series with each of the two
lines and ground. The capacitors provide low im-

pacitor (C1), connected across the lines at the relay,
reduces the amplitude of voltage spikes at the output of the control when switching inductive loads,

pedance paths to ground for high frequency line

thereby preventing interference to nearby electronic

components. The chokes present a high impedance
to these components. If 90-135 Vac exists across

data processing equipment.

4-6

TR
T

ACINPUT
NEMA

5-15P

l
N |

N2 |

____

]

L* —————— J -

ed
T e

S S[

'
.

¢ |
||1|loLiwr Liwf

{

1oa

]

q@ i

YY)

Y'Y YN

|
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e

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rea T rT

r e

r- s T

CO|L |

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—(Fo—
.

.
@

E _ TriLoT cONTROL BOARD
'S
i
|

<o ¢|

(3S '

ofe—l—j

[

yo3

ON Torg] ON

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50uF

|
|
{

REMOTE

LOCAL

21>

2>
N

Va\

/
CP-1734

Figure 4-6

861-F Simplified Circuit Schematic Diagram

Each output line from CBI connects to a normally
open contact on relay K1. The field coil associated

the output of the line filter, pilot lamps I2 and Il
(connected in parallel) light. The neutral line is connected to a 15 A element at circuit breaker CBI.
The phase line is branched; each resulting line connects to a separate 10 A element at CB1. All loads
connected to the power controller (both switched
and unswitched) are controlled by CBI1. If the current through the upper (shared) line exceeds 15 A,
or if the current in either of the remaining lines exceeds 10 A, the circuit breaker trips, removing
power from the load. Power outlets P1 and P2 connect across the output of CBI1. These outlets are
energized (95-135 Vac) whenever the circuit breaker

with K1 is energized by 90-135 Vac from the out-

put of CBI if a relay on the pilot control board
(Paragraph 4.8) is closed. When K1 is closed,
90-135 Vac is applied across outlets P3, P4, P5,
and P6. The two 0.1 uF capacitors, connected
across the lines at the relay, reduce the amplitude
of voltage spikes when switching inductive loads,
thereby preventing interference to nearby electronic
data processing equipment.

Is closed.

4-7

4.8

PILOT

CONTROL

BOARD

Diode D2 provides a current path in the lower section of the coil to prevent closing the relay in instances where pins 3 and 2 are connected but no
connection exists between pins 1 and 3.

CIRCUIT

DESCRIPTION

Figures 4-1 through 4-5 show the pilot control
board simplified circuit schematic. The pilot control
board contains the circuitry which allows remote
turn-on and emergency turn-off of the switched
power outlets in all 861 Power Controller versions.
These functions are accomplished by controlling the
voltage applied to the field coil of relay K1 in the

Closing T1 (the thermal switch) performs the same
function as Emergency Shutdown (connects pins 2
and 3 together). This switch is exposed to the ambient air surrounding the power controller. Temperatures above 160° F close the switch (disabling the
switched outlets). The switch resets automatically

861 Power Controller.

The circuit consists basically of a full-wave rectifier
loaded by the center-tapped field coil of a relay.
Three control lines connect to the board. Pin 3 connects to the center-tapped secondary of the full-

when the temperature drops below 120° F.

wave rectifier transformer. (In the case of the 861-

Placing the LOCAL/OFF/REMOTE switch in the
LOCAL position provides a connection between
pin 3 and the lower portion of the coil to energize
K1, regardless of the state of the Power Request
line on the signal bus. This switch position is normally used for maintenance purposes; operations
on the pilot control board are exactly the same for
situations where a connection is provided between

D and 861-E, the center is returned to chassis
ground through a plug connection.) Pin 2 is the disable (Emergency Shutdown) line from the signal
bus, pin 1 is the enable (Power Request) line from
the signal bus. Two additional lines (from the thermal switch) are connected to the lines associated
with pins 3 and 2.

pins 3 and 1 of the signal bus connector due to closing of a circuit in an external device. A connection
between pins 2 and 3 disables the switched outlets,
regardless of the position of the LO-

When the LOCAL/OFF/REMOTE switch is in the
REMOTE position and pins 3 and 1 are connected,
current flows through the lower portion of the center-tapped relay field coil to the full-wave rectifier
transformer. This action closes relay K1* on the pi-

CAL/OFF/REMOTE switch.

lot control board and causes an energizing potential
to be applied across the field coil associated with
K1 in the power controller, thereby energizing the
controlled outlets. When pins 3 and 2 are connected (Emergency Shutdown is true), current flows

NOTE

In the 861-A, -B, -C, -F, the power supply that provides the potential for closing the relay need not be returned to ground. It can be operated in a floating
configuration where a connection between pins 3 and
2 (as by the thermal switch or Emergency Shutdown)
disables the switched outlets and a connection be-

through the lower and upper halves of the centertapped field coil in different directions, before returning to the power supply transformer. The resultant current through the field coil is less than that
required for holding relay K1* closed. Energizing po-

tential therefore is not present at relay K1

tween pins

and

power is removed from controlled outlets.

and 3 (Power Request) enables the

switched outlets.

4-8

110 O

CHAPTER 5

MAINTENANCE

5.1

GENERAL

The flow charts in Figures 5-3 through 5-5 present

The 861 Power Controllers are constructed of high

a logical troubleshooting sequence for the three fail-

quality components (Figures 5-1 and 5-2) and can

ure modes.

therefore be expected to provide trouble-free performance for extensive periods. No adjustment or

5.2.1

alignment

If correct power is available from the mains,

equipment are required and no fuses are utilized. A

tripped circuit breaker can be caused only by:

5000 ©/V multimeter is adequate for accomplishing

faulty circuit breaker, a low resistance load, or a

all voltage and resistance measurements.

low resistance within the power controller caused

procedures

exist.

special

tools

No Output (Circuit Breaker Tripped)

by component failure.
5.2

PREVENTIVE MAINTENANCE

5.2.2

Preventive maintenance procedures for the power

controllers

consist

periodic

cleaning

and

in-

ter,

components or evidence of overheating, etc.

by holding a flame close to the sensing element,

5.2.3

while the controller is operating and observing that

Emergency

main

cedure by connecting pins 3 and 2 of the Remote

meter leads.

only

with

the

circuit

breaker

are therefore

not

involved.

relays, and diodes. A

external

circuit

use

the

LO-

CAL/OFF/REMOTE switch. With the switch in

con-

the LOCAL position, if T1

troller. Perform all measurements with properly in-

sulated

associated

Control problems can be isolated to either the internal

power

are

faulty thermal switch, T1, can cause loss of control.

NOTE

the

failures

secondary circuit breakers,

ceed as described in the following paragraphs.

within

No Control

These failures are caused by bad cable connections,

Switching Control Bus. Should a failure occur, pro-

exist

bad

switched outlets; the input circuits, line filter, and

Shutdown response to devices on the signal bus can

potentials

are caused by:

improper relay operation, or a faulty circuit

Control

also be checked as a preventive maintenance pro-

Dangerous

mode

breaker.

The operation of the thermal switch can be checked

the switched outlets become disabled.

this

cable connections, open components in the line fil-

spection to detect any mechanical damage to wiring

and

No Output (Circuit Breaker Not Tripped)

Failures within

1s operating properly,

the switched outlets should be enabled. If not, the

Remove the main power plug

problem is within the controller circuitry. If oper-

before attaching or removing test leads.

ation 1s normal when in LOCAL, check the control

signals from the external device.

Failures within the power controller occur in one of

three failure modes:

Once the failing component is identified, it should
be replaced with

one of equal or better quality.

No output (circuit breaker trips)

Drawing

No output (circuit breaker not tripped)

troller components for the 861-A, -B, -C, and -F.

No control (including Emergency Shut-

a complete list of 861-D and 86I-E Power Con-

down and overtemperature)

troller components.

UA-861-0-0 of the Engineering Drawing

Set provides a complete list of 861

Power Con-

Drawings UA-861D-0-0 and UA-861E-0-0 provide

5-1

UNSWITCHED OUTLETS
P1, P2

[

LINE FILTER
F1

INDICATOR LAMP
11

Figure 5-1

SWITCHED OUTLETS
P6, P5, P4, P3

CIRCUIT BREAKER
CB1

PILOT CONTROL BOARD

RELAY
K1

INDICATOR LAMP
12

CAPACITOR
C1

THERMAL SWITCH
T1

861-A,-B,-C,-F Power Controller Component Identification
POWER

SWITCHED

OUTLETS

/ CABLE

STRAIN
RELIEF

BRACKET

THERMOSTAT

CONTACTOR K1

(THERMAL SWITCH)

LINE

._—" FILTER
VARISTOR—

CB1,

CB3-CB6

PILOT CONTROL

BOARD

CIRCUIT BREAKER

INDICATOR LAMPS

UNSWITCHED

OUTLETS @1

CB7

7570 - 2

Figure 5-2

861-D Power Controller Component Identification

5-2

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861-A,B,C,D,.E,F POWER CONTROLLER

Reader’s Comments

MAINTENANCE MANUAL
EK-861AB-MM-002

Your comments and suggestions will help us in our continuous effort to improve the quality and usefulness of
our publications.

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written, etc.? Is it easy to use?

CUT OUT ON DOTT.

INE

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Organization

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City

Department
State

Zip or Country

BT
T

FIRST CLASS

PERMIT NO. 33

MAYNARD, MASS.
~ BUSINESS REPLY MAIL

NO POSTAGE STAMP NECESSARY IF MAILED IN THE UNITED STATES
Postage will be paid by:

Digital Equipment Corporation
Technical Documentation Department

146 Main Street

Maynard, Massachusetts 01754

DIGITAL EQUIPMENT CORPORATION flflgflflau WORLDWIDE SALES AND SERVICE
MAIN OFFICE AND PLANT
Maynard, Massachusetts, U.S.A. 01754 * Telephone: From Metropolitan Boston: 646-8600
« Elsewhere (617)-897-5111

TWX: 710-347-0212 Cable: DIGITAL MAYN Telex: 94-845

DOMESTIC
NORTHEAST

MID-ATLANTIC (cont.)

CENTRAL (cont.)

REGIONAL OFFICE:
235 Wyman Street, Waltham, Mass. 02154
Telephone: (617)-890-0330/0310
Dataphone: 617-890-3012 or 3013

Princeton

MICHIGAN

U.S. Route 1, Princeton, New Jersey 08540

Ann Arbor

CONNECTICUT

Telephone: (609)-452-2940

Dataphone: 609-452-2940

NEW YORK

Meriden

240 Pomeroy Ave., Meriden, Conn. 06540
Telephone: (203)-237-8441/7466
Dataphone:

Long
203-237-8205

Fairfield
1275 Post Road, Fairfield, Conn. 06430
Telephone: (203)-255-5991
NEW YORK

Rochester

Huntington Quadrangle

Suite 189

Southfield, Michigan 48075

Syracuse

MASSACHUSETTS

(212)-582-1300

One Iron Wa

Telephone: (314)-878-4310

710-347-0348

Knoxville, Tennessee 37919

MID-ATLANTIC

Telephone: (615)-588-6571

REGIONAL OFFICE:
U.S. Route 1, Princeton, New Jersey 08540
Telephone: (609)-452-2940

Lanham 30 Office Building

FLORIDA

Orlando
Suite 130, 7001 Lake Ellenor Drive, Orlando, Florida 32809

Telephone: (305)-851-4450

Dataphone: 305-859-2360

Dataphone: 615-584-0571

Atlanta, Georgia 03040
Telephone: (404)-451-7411

OKLAHOMA
Tulsa
3140 S. Winston
Winston Sq. Bldg., Suite 4, Tulsa, Oklahoma 74135

Dataphone: 301 459 7900 X53

CENTRAL

Executive Park

NEW JERSEY
Fairfield
253 Passaic Ave., Fairfield, New Jersey 07006
Telephone: (201)-227-9280
Dataphone: 201-227-9280

Metuchen
95 Main Street, Metuchen, New Jersey 08840
Telephone: (201)-549-4100/2000
Dataphone: 201-548-0144

Telephone: (714)-280-7880/7970

Dataphone: 918-749-2714

PENNSYLVANIA

Pittsburgh

Oakland

7850 Edgewater Drive, Oakland, California 94621
Telephone: (415)-635-5453/7830
Dataphone: 415-562-2160
West Los Angeles

1510 Cotner Avenue, Los Angeles, California 90025
Telephone: (213)-479-3791/4318
Dataphone: 213-478-5626

7901 E. Bellevue Avenue
Suite 5, Englewood, Colorado 80110
Telephone: (303)-770-6150
Dataphone: 303-770-6628

NEW MEXICO
Albuquerque
10200 Menual N.E., Albuquerque, New Mexico 87112
Telephone: (505)-296-5411/5428
Dataphone: 505-294-2330

400 Penn. Center Boulevard, Pittsburgh, Pennsylvania 15235
Telephone: (412)-243-9404
Dataphone: 412-824-9730

OREGON

Indianapolis

TEXAS

Suite 168

INDIANA

Telephone:

Indiana 46224

Dataphone: 317-247-1212

(317)-243-8341

ILLINOIS

Telephone: (503)-297-3761/3765

Plaza North, Suite 513
2880 LBJ Freeway, Dallas, Texas 75234
Dataphone: 214-620-2061

HOUSTON
Dataphone: 312-498-2500

6656 Hornwood Drive
Monterey Park, Houston, Texas 77036
Dataphone: 713-777-1071

LOUISIANA

Telephone: (713)-777-3471

New Orleans

WISCONSIN
Milwaukee

Metairie,

8531 West Capitol Drive, Mil

Telephone: (504)-837-0257

Dataphone: 504-833-2800

UTAH

Salt Lake City
429 Lawn Dale Drive, Salt Lake City, Utah 84115
Telephone: (801)-487-4669
Dataphone: 801-467-0535

WASHINGTON
Bellevue

3100 Ridgelake Drive, Suite 108

Louisiana 70002

Portland

5319 S.W. Westgate Drive, Portland, Oregon 97221

Dallas

Telephone: (214)-620-2051

Chicago
1850 Frontage Road
Northbrook, Illinois 60062

Dataphone: 714-280-7825

Francisco

1400 Terra Bella, Mountain View, California 94040
Telephone: (415)-964-6200
Dataphone: 415-964-1436

21 Beachway Drive, Suite G

Indianapolis,

3700 Chapel Hill Blvd.
Durham, North Carolina 27707
Telephone: (919)-489-3347
Dataphone: 919-489-7832

Dataphone: 513-298-4724

Telephone: (918)-749-4476

Dataphone: 312-498-2500

Dataphone: 714-979-7850

6154 Mission Gorge Road
Suite 110, San Diego, California

COLORADO

Telephone: (513)-294-3323

Telephone: (301)-459-7900

Ex. 78

Dataphone: 305-859-2360

Kettering Boulevard

4900 Princess Garden Parkway, Lanham, Maryland

1850 Frontage Road, Northbrook, Illinois 60062

NORTH CAROLINA
Durham/Chapel Hill

Dayton

Dayton, Ohio 45439

Telephone: (312)-498-2500

2815 Clearview Place, Suite 100

2500 Euclid Avenue, Euclid, Ohlo 44117
Telephone: (216)-946-8484
Dataphone: 216-946-8477
3101

WASHINGTON D.C.

REGIONAL OFFICE:

GEORGIA
Atlanta

Dataphone: 816-461-3100

Cleveland

6311 Kingston Pike, Suite 21E

Telephone: (714)-979-2460

San

OHIO

Knoxville

Telex

Dataphone: 816-461-3100

Maryland Heights, Missouri 63043

TENNESSEE

Marlborough, Mass. 01752
Telephone. (617)-481-7400

San Diego

St. Louis
Suite 110, 115 Progress Parkway

Telephone: (215)-825-4200

Marlborough

MISSOURI

Telephone: (816)-252-2300

1740 Walton Road, Blue Bell, Pennsylvania 19422

Santa Ana
2110 S. Anne Street, Santa Ana, California 92704

12401 East 43rd Street, Independence, Missouri 64055

Digital Hall

4358 East Broadway Road, Phoenix, Arizona 85040
Telephone: (602)-268-3488
Dataphone: 602-268-7371

8030 Cedar Ave. South, Minneapolis, Minnesota 55420
Dataphone: 612-854-1410

Kansas City

PENNSYLVANIA
Philadelphia

ARIZONA

CALIFORNIA

Minneapolis
Telephone: (612)-854-6562-3-4-5

New York, N.Y. 10019

6700 Thompson Road, Syracuse, New York 13211
Telephone: (315)-437-1593/7085
Dataphone: 315-454-4152

Dataphone: 313-557-3063

MINNESOTA

Manhattan

REGIONAL OFFICE:
310 Soquel Way, Sunnyvale, California 94086
Telephone: (408)-735-9200
Dataphone: 408-735-1820

Phoenix

23777 Greenfield Road

Suite 1507 Huntington Station, New York 11746
Telephone. (516)-694-4131, (212)-895-8095
Dataphone: 516-293-5693

Telephone:

230 Huron View Boulevard, Ann Arbor, Michigan 48103
Telephone: (313)-761-1150
Dataphone: 313-769-9883
Detroit

Island

810 7th Ave., 22nd Floor

130 Allens Creek Road, Rochester, New York
Telephone: (716)-461-1700
Dataphone: 716-244-1680

WEST
)

13401 N E. Bellevue, Redmond Road, Suite 111

Telephone: (414)-463-9110

kee, Wi

53222

Dataphone: 414-463-9115

Bellevue, Washington 98005

Telephone: (206)-545-4058/455-5404

Dataphone: 206-747-3754

INTERNATIONAL
EUROPEAN HEADQUARTERS
Digital Equipment Corporatlon International Europe
81 route de I'Aire
1211 Geneva 26, Switzerland
Telephone: 42 79 50

Telex: 22 683

FRANCE

UNITED KINGDOM (cont.)

ISRAEL

JAPAN

READING
Fountain House, Butts Centre

DEC Systems Computers Ltd.
TEL AVIV

Reading RG1 70N, England

Suite 103, Southern Habakuk Street

Digital Equipment Corporation International
Kowa Building No. 16
— Annex, First Floor

Telephone: (0734)-583555

Telex: 8483278

Telephone: (03) 443114/440763

Digital Equipment N.V.

94533 Rungis, France
Telephone: 687-23-33

Sir Winston Churchillian 370

France

Telephone: (76)-87-56-01

Telex: 212-32882

GERMAN FEDERAL REPUBLIC
Digital Equipment GmbH
ICH
8 Muenchen 13, Wallensteinplatz 2
Telephone: 0811-35031
Telex: 524-226

COLOGNE
5 Koeln 41, Aachener Strasse 311
Telephone: 0221-44-40-95
Telex: 888-2269
Telegram- Flip Chip Koeln
FRANKFURT
Am Forstaus Gravebruch 5-7

Telex: 41-76-82

HANNOVER
3 Hannover, Podbielskistrasse 102
Telephone: 0511-69-70-95
Telex: 922-952

STUTTGART
D-7301

Kemnat,

K2H 8K8
Telephone: (613)-592-5111

108 Rue D'Arlon

Telephone: (416)-270-9400

1040 Brussels, Belgium
Telephone: 02-139256

Telex: 25297

Digital Equipment AB

STOCKHOLM
Englundavagen 7, 171 41 Solna, Sweden
Telephone: 98 13 90
Telex: 170 50

Digital Stockholm

VANCOUVER

644 S.\W Marine Dr, Vancouver
British Columbia, Canada V6P 5Y1
Telephone: (604)-325-3231
Telex: 610-929-2006

Oslo 5, Norwa
Telephone: 02/68 34 40

Telex: 19079 DEC N

GENERAL INTERNATIONAL SALES

REGIONAL OFFICE
146 Main Street. Maynard, Massachusetts 01754
Telephone: (617) 897-5111

Digital Equipment Aktiebolag

Marco-Polo-Strasse
1

Telephone: (0771)-45-50-65

Telex: 841-722-393

AUSTRIA
Digital Equipment Corporation Ges.m.b.H.
VIENNA
Mariahilferstrasse 136, 1150 Vienna 15, Austria

COPENHAGEN

From Metropolitan Boston, 646-8600

Hellerupveg 66
2900 Hellerup, Denmark

TWX: 710-347-0217/0212

Cable: DIGITAL MAYN
Telex:

FINLAND
Digital Equnpment AB

94-8457

UNITED KINGDOM

Tltlsmaantxe 6

SF-00710 Helsinki 71
Telephone: (090) 370133

ADELAIDE
6 Montrose Avenue

Reading RG1 70QN. England
Telephone: (0734)-583555
Telex: 8483278

BIRMINGHAM
Maney Buildings

Telex:

337-060

BRISTOL

Telephone

SWITZERLAND
Digital Equipment Corporation S.A.

Boite Postale 23, 1211 Geneva 8, Switzerland

Telephone

EDINBURGH

Digital
MILAN

LONDON

56059

Equipment S p.A

Corso Garibaldi 49. 20121 Milano. ltaly
Telephone: (02)-879-051/2/3/4/5
Telex: 843-33615

Ataio Ingenieros S.A., Enrique Larreta 12, Madrid 16
Telephone. 215 35 43

House

Chester Road. Stretford. Manchester M32 9BH
Telex

668666

printed in U.S.A.

SAO PAULO
Ambriex S.A.
Rua Tupi, 535

Sao Paulo — SP
Telephone: 52-7806/1870, 51-0912

PORTO ALEGRE — RS
Rua Coronel Vicente 421/101
Porto Alegre —
RS
Telephone: 24-7411

Coasin Chile Ltda. (sales only)
Casilla 14588, Correo 15
Telephone: 396713
Cable COACHIL

INDIA
Hinditron Computers Pvt. Ltd.
69/A. L. Jagmohandas Marg.
Bombay-6 (WB) India
Telephone: 38-1615- 36-5344
Cable. TEKHIND

MEXICO
MEXICO CITY

Mexitek,

MELBOURNE

S A.

60 Park Street. South Melbourne, Victoria 3205

Eugenia 408 Deptos. 1
Apdo. Postal 12-1012

Telephone

Mexico 12, D.F.
Telephone: (905) 536-09-10

Australia

(03)-699-2888

Telex:

Telex: 011-2594 Plenty

790-30700

PERTH

MADRID
Telex: 27560

MANCHESTER
Arndale

Telex

Digital Equipment Corporation Ltd.

43 Parker St . Holborn, London
WC 2B 5PT, England

Telephone: (061)-865-7011

01-46-41-91

SPAIN

Management House

01-405-2614/4067

Collie St.
Fyshwick, A.C.T. 2609 Australia
Telephone: (062)-959073

Switzerland

ITALY

Shiel House, Craigshill, Livingston,
West Lothian, Scotland
Telephone 32705
Telex: 727113

Telephone

CANBERRA

Telex: 28 92 01

Rio De Janeiro
—
Telephone: 264- 7406/0461/7625

BOMBAY

Brishane, Queensland, Australia 4000
(072)-293088
Telex: 790-40616

Telephone No. 022 20 40 20 and 20 58 @ and 20 68 93

CH-8050 Zurich,

EALING
Bilton House, Uxbridge Road, Ealing, London W 5.
Telephone: 01-579-2334
Telex: 22371

790-82825

Telephone

20, Quai Ernest Ansermet

Schaffhauserstr. 315

Bristol 651-431

Telex:

133 Leichhardt Street

Spring Hill

ZURICH
Digital Equipment Corp. AG

Fish Ponds Road. Fish Ponds
Bristol. England BS163HO

(08)-42-1339

BRISBANE

GENEVA

29/31 Birmingham Rd . Sutton Coldfield
Warwickshire, Englan

Telephone: 021-355-5501

Norwood. South Australia 5067

Telephone

BRAZIL
RIO DE IANEIRO GB
Ambriex S.A.

CHILE

Telephone: 85 51 86

Digital Equipment Australia Pty. Ltd.

Cable: Digital Helsinki

Coasin S.A.

SANTIAGO

AUSTRALIA

HELSIN

Digital Equipment Co. Ltd.
U.K. HEADQUARTERS
Fountain House, Butts Centre

BUENOS AIRES
Virrey del Pino, 4071, Buenos Aires
Telephone: 52-3185
Telex: 012-2284

Rua Ceara, 104, 2 e3 andares Z2C-29

Suite 202

Digital Equipment Corp. A/S
OSLO
Trondhelmsveten 47

Digital Equipment Corporation De Puerto Rico
407 del Parque Street
Santurce. Puerto Rico 00912
Telephone: (809)-723-8068/67
Telex: 385-9056

ARGENTINA

CALGARY /Edmonton
Suite 140, 6940 Fisher Road S.E.
Calgary, Alberta, Canada
Telephone: (403)435-4881
TWX: 403-255-7408

DENMARK

Stuttgart

TWX: 610-492-7118

MONTREAL

9045 Cote De Liesse
Dorval, Quebec, Canada H3P 2M9
Telephone: (514)-636-9393
Telex: 610-422-4124

SWEDEN

Cable:

PUERTO RICO
TWX: 610-562-8732

TORONTO
2550 Goldenridge Road, Mississauga, Ontario

BRUSSELS

NORWAY

6078 Neu-lsenburg 2

Telephone: 06102-5526

Telex: 32533

Digital Equipment N.V./S.A.

18-14 Nishishimbashi 1-Chome

Minato-Ku, Tokyo, Japan
Telephone: 5915246
Telex: 781-4208

P.O. Box 11500
Ottawa, Ontario, Canada

BELGIUM

9-20 Akasaka 1-Chome
Minato-Ku, Tokyo 107, Japan
Telephone: 586-2771
Telex: J-26428
Rikei Trading Co., Ltd. (sales only)
Kozato-Kaikan Bldg.
No.

Digital Equipment of Canada, Ltd.

CANADIAN HEADQUARTERS

Rijswijk/The Hague, Netherlands

Telephone: 94 9220

16 Rue Du Gal Mangin

Telex: 922-33-3163

CANADA

THE HAGUE

Telex: 26840

GRENOBLE
Digital Equipment France
Tour Mangin
38100 Grenoble,

Tel Aviv, lsr

NETHERLANDS

Digital Equipment France
Centre Silic — Cidex L 225

Telex:

27249

BARCELONA
Ataio Ingenieros S.A., Granduxer 76, Barcelona 6

Telephone: 221 44 66

643 Murray Street
West Perth, Western Australia 6005
Telephone (092)-21-4993
Telex 790-92140

416 Dasmarinas St., Manila
Telephone- 439-68-96
Telex: 742-0352

Telex

790-20740

NEW ZEALAND
Digital

Stanford Computer Corporation
P.O. Box 1608

SYDNEY
P O. Box 491, Crows Nest
N S W Australia 2065
Telephone (02)-439-2563

PHILIPPINES
MANILA

Equipment Corporation Ltd

VENEZUELA
CARACAS
Coasin, C A.

AUCKLAND
Hilton House. 430 Queen Street, Box 2471

Apartado 50939

Auckland, New Zealand
Telephone: 75533

Telephone

Sabana Grande No. 1, Caracas 105
72-8662; 72-9637

Cable: INSTRUVEN