I have a had a 3 phase 11Kw inverter for a few months now. I also have 2 EV chargers (neither GE) - a single phase 7.2Kw and a 3 phase 24Kw (although the current EV can only accept 11Kw). House obviously has a 3 phase supply.
I could never work out why if I charge using the 3Ph EV charger then the inverter was happy to supply the demand (all 11Kw) but if I used the1Ph EV charger then it would only supply 3.6Kw with the rest coming from the grid.
The penny dropped this morning. I think the 3Ph inverter is capped at 1/3 of the overall capacity per phase - ie 3.6Kw in may case.
Iāve asked GE support to confirm but Iām pretty sure this is what is going on.
So a word of warning for those thinking of going the 3Ph route with EV - you will need a 3Ph EV charger as well if you want to avoid grid usage!
Most of the 3 phase inverters does not supply unbalanced loads, meaninig their output will be the same on all phases simultaneously. Having a 11kW inverter youāll have 11/3 kW on a single phase.
Presumably the GE 3-phase inverter does not support unbalanced output, unlike the Solax X3-Hybrid G4.
Even then it looks like a single phase can only go up to 50% of the nominal 3-phase output, so 11 kW inverter can provide up to 5.5 kW on a single phase.
Not sure how many other 3-phase inverters cater for an unbalanced load.
Did GE Support provide any indication of the maximum power on a single phase, or have you found it by experimentation whilst charging your EV on a single phase?
the EV was charging at 7Kw of which the inverter was providing 3.4Kw and the rest was coming from the grid. As the inverter is 11Kw it was 1/3.
Now GE have tweaked the setting I can charge the EV at 7.2Kw single phase (plus other background domestic load). I can also charge at 11Kw with the 3 phase EV charger again all fulfilled by the inverter (but it empties my batteries pretty quickly!)
Hi, glad to hear thereās another 3 phase GE user in the world!
can you give more details of the unbalance setting? Our config suddenly lost this ability when givenergy were trying to fix problems of the battery alarming when running off grid (yes we were very careful to keep each phase load <3kw when off grid, but it seems to crash anyway after a few hours)
There is a setting on your inverter known as āEnable Three-Phase unbalanceā this setting while disabled (by default) will balance your load across each phase to achieve ānet zeroā import/export. This will import on some phases while exporting on others, this will only be useful if your energy supplier has this net zero option for 3 phase properties.
I have observed changing this setting also changes inverters ability to ābalanceā with the grid. Graph below shows the behaviour of each of the grid phases measured by an independent device. The net is very often an import. Not always much but 50w over the year soon adds up!
Thanks,
Does that mean youād prefer to stay ābalancedā? I guess the net loss has to be offset against the times you put a kettle on & it draws from the grid.
I think the inverter does not balance the battery/grid particularly well in either setting but probably marginally worse with the setting to allow unbalanced load. I think on balance (forgive the pun) I prefer to be able to satisfy an unbalanced demand.
I would be interested as to how well other manufacturers perform in terms of controlling net import/export. Maybe my expectations are unrealistic.
