Digital Equipment StorageWorks UltraSCSI DS-BA370 Series, User Manual

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Environmental Monitoring Unit (EMU)
UltraSCSI RAID Enclosure 3–17
Monitoring Power Supply Operation
Even when there are four operational power supplies, it is possible that a
power supply problem will cause one or both of the dc voltages to be too
low. Both the PVA and the EMU monitor power supply operations to ensure
that the dc voltages are within the ranges specified in Table 3–5.
Table 3–5 DC Voltage Ranges
Nominal Voltage + 5 V dc + 12 V dc
Minimum Voltage
+4.7 V dc + 11.4 V dc
When there are at least four operational power supplies both the minimum
voltages, which are sufficient to run the system, are present. Fewer than
four operational power supplies cannot maintain the minimum voltages.
Should this occur, the EMU will notify the array controller. The EMU can
automatically initiate the standby power mode when controller directs or the
PVA .
_____________________ Note ______________________
Only the EMU monitors the I/O 5 V dc
TERMPOWER. The PVA does not monitor these voltages.
________________________________________________
Error Condition Reporting
The EMU LEDs (see Table 3–6) display the enclosure, the temperature
status, error conditions, individual blowers status, and blower bank status
(When the enclosure is functioning properly only the Power LED is on.)
The figures describe:
•
The EMU LED display
•
The enclosure status associated with each display
•
The probable cause of the error condition
•
The actions recommended to correct the problem