Chapter 6. Expansion Installation; Installation; Rs-485 Cable Interconnection; Scsi Cable Connection - IBM 7012 G Series Service Manual

Chapter 6. Expansion Installation

This chapter describes how to connect one or more additional expansion units to the
existing system configuration. In addition it illustrates briefly the general rules to disconnect
a unit from the system configuration.
For details about setting the system up, refer to 7012 G Series Expansion Unit Setup
Procedure , order number SA23-2754.

Installation

Looking at the unit from the front, the expansion units must be installed starting on the left
side of the base unit.
The expansion units must be connected using appropriate cables, according to the system
configuration. Follow the procedures below to interconnect the expansion units.

RS-485 Cable Interconnection

The RS-485 cable interconnection must be performed from unit to unit, in a daisy chain
fashion.
1. Connect one of the two connectors of the RS-485 cable (it is not important which one) to
the RS-485 connector on the rear side of the base unit.
2. Connect the other connector of the RS-485 cable used in the previous step to the
RS-485 IN connector located on the expansion unit.
3. If no other expansion units are to be installed, insert an RS-485 terminator plug in the
RS-485 OUT connector located on the expansion unit. Otherwise, connect the other
expansion units using the same criteria used for the base expansion unit connection.
Remember to install a terminator plug in the RS-485 OUT connector located in the rear
side of the last expansion unit that you are installing.
Exp Unit 2

SCSI Cable Connection

Each disk unit must be connected to the base unit through a dedicated SCSI cable.
1. Connect the SCSI cable to the appropriate base unit connector.

Recognizing the New Unit

Use the appropriate software procedure to make the system able to recognize the units that
you are connecting. Refer to your 7012 G Series Expansion Unit Setup Procedure or your
operating system documentation for detailed information.
Exp Unit 1 Base Unit
Terminator
Exp Unit 4 Exp Unit 3
Expansion Installation
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