APC 900XL Power Supply User Manual


 
Page 33
7.0 Difficulty
7.2 Battery replacement check
You can expect to receive 3 to 6 years of service life from the UPS's Battery packs when
installed in a cool, dry location. Battery life is shortened when operated in an environ-
ment where the ambient temperature is normally above 30°C (86°F).
The UPS automatically performs a battery test upon start up and, if left operating, every
14 days thereafter. This test actually loads the battery for a brief time and will detect a
weak battery before it is put into service during a power failure. If the battery is too weak
to support the load during this test, the UPS will instantly return to on-line operation. The
UPS will illuminate the Replace Battery indicator when it is detected that the battery
packs can no longer sustain sufficient charge. This means that the UPS would be unable
to provide power for longer than half the normal interval (see section 9.9) during an
extended utility failure.
If the UPS illuminates the Replace Battery indicator, perform the following procedures
to be sure that the batteries need replacing.
7.2.1 Use the UPS's Line voltage bar graph to check that the utility voltage is within a
normal range. The UPS will charge the batteries at a slower rate when operated from very
low input voltages. Where low line voltages and frequent disturbances are common, set
the UPS's Option switch 1 to the on ( I ) position - see section 5.0.
7.2.2 Allow the UPS to charge the batteries for at least 16 hours following an extended
utility failure.
7.2.3 Recheck the UPS's batteries by conducting a battery test. Press the I/Test button to
initiate the battery test.
7.2.4 If the Replace Battery indicator does not illuminate following the battery test, the
batteries do not require replacement. Extended storage without recharge, or successive
power outages can cause false indications.
7.2.5 If the Replace Battery is illuminated following the battery test, the batteries are worn
and need to be replaced.
7.2.6 Call the Customer Service phone number given on the cover of this manual to obtain
information about battery replacement service or battery replacement kits.
Note: Please see the battery cautions at the beginning of this section.