Compaq RAID ARRAY 3000 EK-SMCPO-UG. C01 - Manual (Page 85)

Expansion Pedestal Option 4-5
Compaq Confidential – Need to Know Required
Writer: Bob Young Project: RAID Array 3000 Pedestal Storage Subsystem Hardware User’s Guide Comments:
Part Number: EK-SMCPO-UG. C01 File Name: e-ch4 Expansion Pedestal Option.doc Last Saved On: 12/4/00 1:49 PM
The SCSI bus extender module extends the allowable electrical length of the
bus to accommodate longer physical SCSI cable connections between the base
and expansion pedestals.
The EMU is an internal circuit board, which monitors the operation of the
pedestal (Figure 4–4). The EMU monitors power supply voltages, fans,
temperatures that are reported to the user, and controls (turns on and off) the
audible alarm and status LED on the front panel of the pedestal. It is connected
to the SCSI bus and powered by internal cabling. The following external
components on the rear panel of the expansion pedestal are part of the EMU
board:
■ The alarm switch (S1) that enables (up) or disables (down) the audible
alarm
■ The External Fault Condition connector allows the EMU to monitor the
status of a user-selected device
3000-37
EMU
Figure 4-4. EMU circuit board location