Sleeping
Happens when the wind turbine’s voltage is less than the battery voltage
or charger current is below the minimum cutoff (Low cutoff) current. This
may also appear briefly during the day when the MPPT is transitioning
between certain states, and because of other conditions.
Absorb
There is an external DC source (wind generator/hydro) keeping the
battery at or above the absorb set point.
Wakeup
As the turbine’s open circuit voltage (Voc) rises above the battery bank’s
voltage by approximately 2 volts, the MPPT controller gets ready to work
to deliver the best possible power to the batteries. During this period, the
MPPT is calculating the PWM (Pulse-width modulation) duty cycles by
turning on power supply voltages in the proper sequences, and making
internal calibrations. At wakeup, the MPPT closes its relays and will then
start sweeping the input voltage, (the “initial” sweep), towards the battery
voltage. This may happen numerous times at both dawn and dusk until
there is enough power from the turbine to keep charging the battery
bank. Wakeup is also a time when the MPPT controller acquires a new
Voc.
Sweeping
In Auto-Sweep MPPT mode, the MPPT is either doing an initial sweep of
the turbines voltage from Voc towards battery voltage after wakeup, or
is doing a periodic dithering mini-sweep to stay on the max power point.
Below 5 amps of battery output current, this will flash briefly as the MPPT
operates at the Park MPP voltage. This signal may also appear briefly if
the MPPT has reached the max battery current setting and is raising the
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