I run 2 Quattro 48/5000 inverters independently on my 50A RV because Victron Energy does not support this configuration, the L1 inverter is connected to a Cerbo GX and the L2 inverter is connected to a VE.bus dongle for control through my phone.
The charger in both inverters is normally disabled as I only want to charge from the solar panels.
I almost always run L1 in "Inverter Only" mode (ignores grid) and L2 in "Inverter Only" or off. However, I sometimes switch one of the inverters to "On" if I want to run a air conditioner longer than I have solar power to support it (5000W of solar panels).
The problem is that my RV is equipped with an Energy Management System (EMS) which is intended to shed loads when the shore power is insufficient. When I have shore power available, even though I am not using it, everything is fine. I just need to manage the loads myself which is not difficult. When I don't have shore power available, the EMS does not allow me to turn on any of the air conditioners or the electric water heater because it believes there is no input power available.
In theory at least, I could solve this problem by plugging the 50A main RV power plug through a 50A to 20A adapter into the outlet in the RV electrical bay. The EMS would see input power, default to 30A input source because it is "In Phase", and let me run one air conditioner or the water heater. The inverters are ignoring the grid because they are in "inverter only" mode, so nothing bad should happen.
The problem would arise if I forgot to unplug the RV and switched the inverter to "On". The inverter would see input power available, try to use it, but that would turn it off. Then the inverter would not see input power, start inverting, and the cycle would repeat.
I understand this is far from a desirable solution (but neither is not being able to use the power stored in the batteries (24Kwh) when completely off grid), the question is whether this is likely to cause permanent damage to the inverter (and after how long)?
A modification of this idea is to plug a small UPS into the outlet powered by the inverter and the RV plug into the UPS. There would still be an oscillation if the inverter was turned on as the UPS battery was exhausted, but the cycle would likely be minutes and not milliseconds. Anyone see a problem with this solution?
Any thoughts would be sincerely appreciated. I have a significant problem to solve either way.
