Owner`s manual

When the charger is powered and is being used as a DC power supply / UPS, the
output voltage drops when the DC load is switched on or increased.
The charger is being forced into current limit condition. The load is trying to draw current
more than the current limit value of the charger – 45 A for Normal operation & 22.5 A +/- 1
A for “Half Power Mode” for SEC-1245A and 25 A for Normal operation & 12.5 A +/- 1 A
for “Half Power Mode” for SEC-2425A (the current limit value is the maximum specified
charging Amps). Once the load current reaches the current limit value, the current limit circuit
is activated and the output voltage drops. Some loads like motors, compressors, incandes-
cent lamps, halogen lamps, heating elements, relays, coils, capacitors etc. draw very large
inrush / starting currents which may reach up to 10 times their normal operating currents.
Ensure that the starting / inrush current or the maximum operating current of the load is lower
than the current limit value of the charger. Do not use a load that draws more than 45 A (22.5
A +/- 1 A for “Half Power Mode”) for SEC-1245A or more than 25 A (12.5 A +/- 1 A for “Half
Power Mode”) for SEC-2425A. Once the load current is reduced below the above limiting
values, the charger will recover automatically.
The battery is getting over charged / overheated / loses water or boils.
There is an external load connected to the battery when it is being charged. 3-stage charging
is recommended for charging stand-alone or unloaded batteries (there is no load connected to
the battery when it is being charged). If a load is also connected simultaneously, a part of the
charger’s output current will be diverted to this load. Thus, the charger may remain locked in
Stage 2 if the current drawn by the load is more than the preset value of threshold current
determining transition from Stage 2 to Stage 3 .This will lead to overcharging, overheating and
loss of electrolyte.
For charging a battery when a load is also connected simultaneously, Stage 2 voltage should
be the same as Stage 3 voltage (Stage 2 is disabled). Select “Loaded Battery” with the help of
DIP Switches S1 and S2 of the set of 4 DIP Switches (5) – See under “Selecting the Type of
Battery and Charging Stages”.
Two banks of batteries are being charged and the batteries in the two banks are in dissimilar
state of discharge When charging more than one bank of batteries at the same time using 3
Stage Charging, ensure that the batteries in the banks are in a similar discharged condition. If
one bank is completely discharged and another is almost fully charged, the bank that is fully
charged will be subjected to over charge condition during the time when the charger remains
in Stage 2 for charging the completely discharged bank.
If 2 banks of batteries are required to be charged and they are at different discharged condi-
tions, select “2 Stage Charging” with the help of switches S1 and S2 of the set of 4 Dip
Switches (5) (both S1 & S2 in off condition) – See under “Selecting the Type of Battery and
Charging Stages”.
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