NonStop S-Series Operations Guide (G06.24+)
Power Failures: Preparation and Recovery
HP NonStop S-Series Operations Guide—522459-007
15-4
Recharging Drained Batteries
•
Hardware problems:
°
A power monitor and control unit (PMCU) failure has occurred.
°
A battery failure has occurred.
°
A processor multifunction (PMF) CRU hardware failure has occurred.
The failed hardware component might need to be replaced.  Refer to the CSSI 
Web.
Recharging Drained Batteries
Batteries are automatically recharged when the system is running. Table 15-1 lists the 
expected recharge time for a battery that has been fully discharged (drained). 
Power Failure Recovery Operations
After a power failure, if AC power is restored to a NonStop S-series server while the 
batteries are still maintaining the contents of the memory, the server automatically 
resumes operation within minutes. The system begins processing at the point it was 
interrupted. 
In rare cases, a power failure can last long enough to leave the system with some 
processors down because the batteries were drained to the point where they can no 
longer maintain processor memory, while other processors are able to resume 
operations. If the power failure lasts long enough to drain the batteries completely, the 
service processors (SPs) shut down the system. When power is restored, the operator 
must then restart the system. 
Procedure to Recover From a Power Failure
After power is restored:
1. Log on to the OSM or TSM Low-Level Link and then:
a. From the toolbar, click Processor Status.
b. If some but not all processors are running, halt the running processors.
c. Restart the system if necessary, using the OSM or TSM Low-Level Link to 
initiate a system load.
Table 15-1. Battery Recharge Times Following a Full Discharge
Time State of Charge
1 hour 80% of charge
5 hours 90% of charge
48 hours 100% of charge
Note: Partial discharges require less recharge time.










