EPS AIO SoC Thresholds

Hi all,

Finding my way around my new AIO/Gateway install, bought specifically for its usage as a EPS due to frequent grid power cuts where we live. There have been, and remain, a few issues, but we are beginning to work through them. However one has got us stumped.

When performing a grid test, the AIO EPS does not kick in, unless the current SoC is (some as yet undefined amount) higher than the set reserve level. For example, if I set the reserve level at 50%, and the current SoC is 55%, when I do a grid test the EPS does not work, and it just behaves as a normal power cut would do (everything dies).

If I then drop the reserve level to 20%, the EPS will work as expected.

This seems useless to me - during the day the AIO will be discharging, particularly at this time of year without enough solar to meet demand, to help meet house draw. Assuming by evening it is then down to the reserve level, if I then have a power cut, the EPS is useless, and I can’t stop this happening.

I found the battery cut off % limit as well, and this is set to 10%. My understanding is that this should be the limit at which everything stops.

So my question is why does the EPS not work in this way - reserving the 50%, activating the EPS in a power cut, and continuing to run until the cut off limit?

Many thanks.

WillWillWill There's functionality in the AIO to shut down your Solar PV if the grid is down, the sun is shining and there's nowhere for the generated energy to go. I think this happens when the battery SOC is 95% or over, and it works by the AIO inverter raising the ac frequency to 52Hz (or similar), at which point the Solar PV inverter is supposed to shut down (mandated by DNO specs). It doesn't explain the effect of changing the reserve level, but maybe it's related in some way (or a bug!)

What firmware versions are you on? I had an issue on 612 where the EPS took 20 seconds to kick in if the battery pause discharge was on even if the EPS was on and set to 0 seconds. This is apparently fixed in 613, which I am now on, but I haven't had a chance to test that particular scenario yet but my EPS works albeit on occasions a circuit in my consumer unit may trip but it isnt really repeatable.

T-M thanks for the response. I am not entirely sure on this one, although I can say with certainty that this is happening even when the sun in barely shining and the battery is at 50%, as these were the conditions we were testing under yesterday. I think we had SoC 55%, about 200W PV and 800W load.

With reserve set to 50% and cutoff at 10%, AIO doesn't kick in EPS when grid is cut, drop the reserve to 20% with the exact same conditions, works just fine.

Hopeful thanks also. Firmware on the AIO is 613 and Gateway is 10.

I haven't yet got any battery charge or discharge schedules set, or using the pause mode. Trying to keep everything simple until the basics work, but unfortunately not even managing that at the moment.

Sounds like yet another bug so I would recommend getting your installer to raise it as he should have more luck that you would with support.
I guess GE's thought line might be that you may wish to preserve some battery for "future" use, however you would also logically want to preserve some battery when the grid is there to be used for EPS. On that basis I would expect reserve to hold charge for EPS and cutoff to be the hard stop for "future" use although without power it does make it hard to change a setting once the battery has stopped.
Clearly its not working like we would expect at the moment!