Bulk
This stage provides the maximum power to the battery -- voltage
increases while charging.
A bulk charge is automatically initiated when the battery voltage is below
the absorb and float voltage set points. The bulk charge will continue until
the absorb voltage set point is achieved.
Absorbing
This stage limits the amount of power going to the battery -- the voltage is
heldconstant. The absorb charge will continue for the duration of the bulk
cycle or until the 2 hours (default) absorb time limit is reached. Example,
if a bulk charge takes 1 hour to reach the absorb voltage set point then
the absorb charge will continue for 1 hour as well. However, if a bulk
charge takes 3 hours to reach the absorb voltage set point then the
absorb charge will last for 2 hours only. A bulk charge will be re-initiated if
the battery voltage is not sustained at the absorb voltage set point.
Float
This stage reduces the charging voltage to prevent overcharging of the
batteries. A float charge follows after the absorb charge is completed.
The MPPT will not re-initiate another bulk charge if the float voltage set
point is not sustained, however, it will continue to charge the battery
until the float voltage set point is achieved. Note: A bulk charge can be
initiated if the battery voltage falls below the float voltage set point if the
re-bulk (ReBV) voltage option is set.
Understanding the various modes
The modes of operation will change occasionally during the day based on
turbines output and battery system state of charge. The MPPT operating
modes are displayed through the LED’s.
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