MP2 12/3000/120-50: A generator is supplying an RV trailer with 120V air conditioner. AC input limit for Powerassist set to 15.8A. When the air conditioner compressor starts, the Powerassist engages. After the compressor has started, the MP2’s AC output drops below 12A and AC input from the generator drops to 9A-10A. The generator could now easily carry the full load but Powerassist remains engaged until the AC compressor stops completely. I understand that the Assist Current Boost Factor only affects the boost current for the first 50ms. Why is PowerAssist not disengaging when the load drops so low?
@JJKELLY an interesting problem and I can imagine quite annoying. The Multiplus has a checkbox in the programming section called “dynamic current limit.” This is a feature that extends the range of power assist to make it easier on small generators by not dumping shock load on them. Perhaps Dynamic Current Limit could be switched off and check the operation of your power assist again. I think you may find it works as you expect if that feature is disengaged.
PowerAssist isn’t a simple “threshold switch.”
It works as a PID-type feedback loop that slowly adjusts charge and discharge current to stabilize generator load around the AC-in limit.
When assist mode kicks in, the inverter “virtually lowers” the generator’s seen load by injecting current from the battery. The system then ramps back down only when it detects the generator voltage and frequency have stabilized for several cycles — and this ramp is deliberately slow to avoid oscillation or hunting.
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