Operation
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The battery must remain in the Absorption charging
stage for a cumulative 120 - 150 minutes, depending on
battery type, before transition to the Float stage will occur.
However, Absorption time will be extended by 30 minutes
if the battery discharges below 12.50 volts (12V system) the
previous night.
The Absorption set-point is temperature compensated if the
RTS is connected.
Float Stage
After the battery is fully charged in the Absorption stage,
the ProStar MPPT reduces the battery voltage to the Float
voltage set-point. When the battery is fully recharged, there
can be no more chemical reactions and all the charging cur-
rent is turned into heat and gasing. The float stage provides
a very low rate of maintenance charging while reducing the
heating and gasing of a fully charged battery. The purpose
of float is to protect the battery from long-term overcharge.
The green SOC LED will blink once every two (2) seconds
during Float charging.
Once in Float stage, loads can continue to draw power from
the battery. In the event that the system load(s) exceed the
solar charge current, the controller will no longer be able to
maintain the battery at the Float set-point. Should the bat-
tery voltage remain below the Float set-point for a cumula-
tive 60 minute period, the controller will exit Float stage and
return to Bulk charging.
The Float set-point is temperature compensated if the RTS
is connected.