RA90/RA92 Disk Drive User Guide

This document is a User Guide for the Digital Equipment Corporation RA90 and RA92 Disk Drives, published in 1988 and 1990.

Key features and information include:

• Product Overview: The RA90 (1.216 GB formatted) and RA92 (1.506 GB formatted) are DSA/SDI family moving-head, random-access disk drives with a 2.77 MB/s transfer rate. They feature non-removable thin film media, three internal microprocessors, extensive resident diagnostics, and a multifunction Operator Control Panel (OCP).
• Maintainability & Servicing: The drives use modular Field Replaceable Units (FRUs) for easy servicing. Crucially, installation and service must be performed by trained Digital Customer Services engineers due to hazardous voltages. Customer preventive maintenance is limited to monthly cleaning of the storage array air vent grill and general equipment care.
• Dual-Port Capability: Supports static dual-port mode, allowing sharing between two controllers (one active at a time).
• Installation: Covers site preparation (power, thermal stabilization, floor loading), unpacking procedures (drives weigh 31.8 kg/70 lbs, handle with care, mandatory 24-hour thermal stabilization), and general guidance on installing SDI cables and power cords (referencing other system-specific documentation for detailed steps). It also provides instructions for voltage selection (120V/240V), emphasizing the need to match drive and power controller settings.
• Operating Instructions: Details the OCP's functions, including power-up diagnostics, acceptance testing (spun-down and spun-up drive diagnostics), programming the drive unit address (0-4094), and various operating modes (Normal, Fault Display, Test).
• Diagnostics: Explains drive-resident diagnostics that run automatically (power-up, idle-loop) or can be initiated via the OCP, testing various hardware areas.

• User Precautions & Recommendations:

  • Data Recovery: Users are responsible for data backup (file duplication, journaling) as data on an inoperable Head Disk Assembly (HDA) is not recoverable.
  • Operating Environment: Recommended operating temperature is below 25°C (77°F) for increased reliability, though the drives can operate from 10°C to 40°C.
  • Electrostatic Discharge (ESD) Protection: Emphasizes the mandatory use of properly grounded ESD wrist straps when handling static-sensitive components to prevent product damage.

• Troubleshooting: Provides basic power-up troubleshooting steps and advises users to contact Digital Customer Services for most error codes and unresolved problems.

In summary, the document serves as a comprehensive user guide, emphasizing professional installation and maintenance while providing essential operational and preventative information for the customer.