Operation
41
Battery Shutdown (60 Minutes)
During extended outages or deep sags of m ore than 15 minutes, the shutdown voltage limit will ramp
up gradually to this 60-minute limit to prevent lengthy discharge and possible battery damage. The
battery circuit breaker opens when the battery voltage and the shutdown limit are equal for five sec-
onds. See the Battery Time screen for more information. Also refer to the battery manufacturer’s
manual, available on the manufacturer’s Web site.
Battery Rating (100%)
This setting is the full load discharge rating of the battery in kilowatts for the rated backup period. A
typical rating might be 500 kW for 15 minutes.
Battery Rating
This setting is a battery discharge rating in kilowatts under partial load for an extended period, typi-
cally 40 to 60 minutes. The UPS uses the two battery shutdown voltage settings and the two battery
discharge ratings in computing rated and calculated time remaining during a discharge event.
Temperature Limit Setting (Optional)
This setting is visible when the optional battery-temperature-compensated charging board is
installed. This setting determines the battery temperature that triggers the Battery Overtemp alarm.
The alarm becomes active when the temperature setting is exceeded for more than one minute.
NOTE
The Low Battery alarm setting is designed to be us eful at full load battery discharge rates. It is
typically set for 10 volts above the 60-minute Battery Shutdown voltage, to provide some
measure of warning under all circumstances. If the discharge period extends past 15 minutes
(i.e., the load on the UPS is less than full capacity), the Battery Shutdown voltage setting is
gradually and automatically increased to protect the batteries from deep discharge. The Low
Battery alarm setting is not automatically increased and will give proportionately less
warning for longer discharge periods. Instead, the operator should consult the Battery Time
screen or Present Status screen to see the calculated time remaining based on actual usage
during the discharge period.