question

The battery is undersized for the inverter. This is a common problem for systems in SA which have too little battery, and particularly affects batteries with the PACE BMS (Hubble, BSL, FW e-tower).

The solution is always more battery.

The ripple is a good indication.

The battery is rated for max 105A, in reality less, for an inverter that can surge beyond that.

The issue in SA, is that the grid, in places, tends to brown-out, so while you have nominal loads, the cutover puts a sudden surge requirement on the pack which causes it to cut out, hence low battery and the 30 second restart.

Your choices are: more battery or different battery, but you should aim for something with more headroom on the discharge current.

We just don't see this on systems where a better battery to inverter ratio is implemented.

It seems a good rule of thumb to avoid anything with a PACE BMS. You can also check if there are any firmware updates for the BMS, never hurts.

You can try make this Hubble's problem, they should be able to analyse the BMS data but I wouldn't hold my breath, like most suppliers of mediocre batteries, they always blame the inverter.

Feel your DC battery fuses. Check if it feels hot to touch when the error occurs. Even if the fuse passes the continuity test, it is likely that the fuse is causing the issue. Then check your battery cables and make sure everything is torqued to spec. Lastly, swop out the fuse disconnect (fuse holder).