Testing The Ups - Liebert PB Series User Manual

The battery charger board is designed to supply a maximum of 7.5 A
DC charging current. Depending on the externally connected
batteries, the appropriate setting should be done before connecting the
batteries. The battery manufacturer recommends a charging current
which is 10% of the AH capacity rating. Based on this, battery charger
should be set closely to or next higher value to the required battery
charging current.
Remove the screws on sides and rear of the UPS panel to gain access
to the battery charger board. The battery charger board is located
centrally on the top side of the UPS and can be identified by the
heatsinks mounted on it and a cooling fan mounted next to it. The
battery charger board has DIP microswitches with on-off positions as
shown below. The status of these microswitches decides the charging
current for a set of battery bank. A step of 1.5 A is available, hence
current setting of 1.5A, 3A, 4.5A, 6.0A & 7.5A is possible by setting
these microswitches.
For example, if a battery bank of 40 AH is being used, the charging
current will have to be set to 10% of 40 AH, which is 4A. Since the
setting for 4 A is not available , the next setting of 4.5 A which is 3/5
Imax as shown below will have to be set.
This setting will ensure the proper charging of the batteries with built-in
current limit of charger circuit
Danger : The setting of battery charging current is very important
for the externally connected batteries. If this is not done
the batteries may bulge or get damaged due to improper
setting of charging current.
ON
1 2 3
4
OFF
6.

TESTING THE UPS

SWITCH STATUS
1, 2, 3, 4 : OFF
1, 2, 3, : OFF, 4 - ON
1, 2, - OFF, 3, 4, - ON
1 - ON, 2, 3, 4 - OFF
1, 2, 3, 4, - ON
CURRENT SETTING
7.5 A I max
6.0 A 4 / 5 max
4.5 A 3 / 5 max
3.0 A 2 / 5 max
1.5 A 1 / 5 max
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