Technical data

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Compaq HSZ80 Array Controller ACS Version 8.3 Maintenance and Service Guide
This four-minute polling continues for up to 10 hours—the maximum time it should
take to recharge the batteries. If the batteries have not been charged sufficiently after
10 hours, the controller declares them to be failed.
Battery Hysteresis
When charging a battery, write-back caching will be allowed as long as a previous
down time has not drained more than 50 percent of a battery’s capacity. When a
battery is operating below 50 percent capacity, the battery is considered to be low and
write-back caching is disabled.
CAUTION: Compaq recommends that you replace the ECB every two
years to prevent battery failure.
IMPORTANT: If a UPS is used for backup power, the controller does not check
the battery. See
HSZ80 Array Controller ACS Version 8.3 Configuration and CLI
Reference Guide
for information about the CACHE_UPS and NOCACHE_UPS
switches.