APC DP300E Series Power Supply User Manual


 
34 User Guide Silcon DP300E Series 480V 400-500kVA
7OA0004 US rev. 02
Preventive Maintenance
8.5 Battery monitor test
The battery monitor has two main purposes:
1. To show remaining back-up time, when the UPS operates in battery operation
2. To monitor the condition of the battery, during test or normal battery operation
8.5.1 Back-up time
The back-up time in the batteries is shown in the display, when UPS runs in battery
operation. The back-up time is valid for the actual load on the UPS, however, if load
changes, the actual back-up time will change too. The shown back-up time is also
compensated for battery temperature changes, if a temperature sensor has been
installed and calibrated.
8.5.2 Monitor function
During a test the battery monitor discharges 25% of the energy in the battery.
The monitor can detect, when a battery is weak, or if it is defective. The UPS gives
an alarm, if one of the errors is detected. The criteria for the alarms are:
Battery weak alarm is given, when the measured battery capacity is less than
75% of the original capacity.
Battery detect alarm is given, when the measured battery capacity is less than
50% of the original capacity.
8.5.3 Functionality of battery test
The test can be started manually or automatically from the user stack.
The automatic test is enabled in the user stack and can be set to 3 or 6 months.
When automatic test is enabled, the UPS performs a battery test every 3 or 6
months independent on manually activated battery tests. If conditions for starting a
test are not correct at the moment where automatic test is going to start, the test
will be skipped.
Conditions for starting a battery monitor test:
A battery monitor test can only be started if the battery is fully charged
(capacity = 100%).
The UPS is operating in normal operation.
The test is interrupted if:
The error “battery defective” is encountered.
If utility fail during battery monitor test.
The red OFF button is pressed.
If “EPO” emergency power off is activated.
If external shutdown is accepted.
After the test the UPS returns to normal operation.
The battery monitor test can be performed with load in the range of 10-150%. If the
load exceeds this level, faulty results may occur.