Sunforce 600 Watt MARINE WIND TURBINE, User Manual

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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.
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 turbines operating voltage to
keep the battery current from exceeding the maximum battery output current limit setting.
Absorb There is an external DC source (wind generator/hydro) keeping the battery at or above
the absorb set point.
Bat Full The MPPT is waiting for the battery voltage to fall to just below the float voltage set point
before continuing with the float stage. This may also be displayed when external DC charging
sources are present.
Float
The charger is in constant-voltage state at a lower voltage than in absorption mode
(approx. 13.8V for a 12V system). This allows the battery to draw just enough current to make up
for its internal leakage current. When the charger is in this mode, the battery may remain
connected to the charger for all of the battery's service life with no damage to the battery.
Re-Cal There is certain abnormal conditions that can confuse the current measuring method in
the MPPT. When and if this happens, the MPPT will temporarily stop and re-calibrate. This may
sometimes happen because of negative current, i.e., current coming out of the input terminals
instead of into the input terminals turbine breaker. A new voc is also acquired during a Re-Cal.
Troubleshooting Guide
MPPT does not boot/power-up
1. Check battery connection and polarity. Reverse polarity or improper connection will cause
power-up issues.
2. Is the battery voltage greater than 10.5v? (Measure the battery-side of 4 Position Terminal
block)
A battery voltage less than 10.5v may not power up the MPPT.