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5
MAINTENANCE
5.1 Run Time Testing
This test determines how long the battery can provide backup power, and it should
be done at least once a year. It is load–dependant so it takes from several minutes
to many hours to carry out. The batteries are discharged, so it should not be done
when critical equipment is running that depends on the UPS's output.
PURPOSE: Describes how to measure the battery's
backup time.
Available Backup Time=
Start Time–Low Battery Time
Start
Switch the input circuit
breaker OFF. The On
Battery LED turns ON.
Record this start time
Record the time when
the Low Battery LED
starts flashing.
Continued Next Page
Start Time
Low Battery Time
Subtract this time from
the start time.
This is the available
backup time.
NOTE: The test can be ended now by turning the circuit breaker back on.
The next step shuts down the UPS.