I See Electromagnetic Fields!
- Mar 28, 2020
Also forgot to mention, I have a single phase 15KW (240V, 63A) connection, but need 10KW of 3-phase intermittently for the workshop. The batteries help here since I can use an off-grid 3-phase inverter and not risk blowing the main breaker if my wife decides to make a cup of tea (which is a 3KW kettle) while I'm using the machines in the workshop. All of the 3-phase hybrid inverters (and single-phase paralleled hybrid inverters) that I've seen require a 3-phase main connection unless they are in off-grid mode.
SMA and Victron battery inverters can be connected as either split-phase or 3-phase.
I think I've tested that a pair of Sunny Island with 120V single phase coming in from grid or generator can produce 120/240V split-phase, so would also do 120/208Y. Each 120V inverter has its own relay to connect input. The relay is 56A max so 120V x 56A would be the maximum power it could be fed by the grid. As 3-phase, it could supply 3x that with the balance coming from battery.
What in the shop do you want to power with 3-phase? A VFD can rectify 240VAC and deliver 3-phase. I have that on a 2 HP pool pump. One issue I saw as that if disconnected from the grid, the harmonics or poor PF of the VFD upset a transformerless inverter. A transformer type should be OK. (I had transformer type Sunny Island 6048US and Sunny Boy SWR2500U, also transformerless 10000TLUS operating.