Charging AIO battery with gateway and hybrid inverter using petrol generator

Having been without power for 3 days now, I'm interested in how I can charge my AIO battery using a petrol generator when in island mode. At the moment, my generator is just keeping fridges going via extension leads.

I do not want to power the house via the generator, only keep the battery topped up. The battery is able to supply all my power needs (base load of around 500W).

Ideally, the PV side would work as normal and also charge the battery in parallel.

Does anyone know if this is possible?

I assume that the AIO Gateway acts as a transfer switch so when in island mode, any generated power (whether PV or generator) would never hit the network but again, confirmation would be useful.

Youtube videos suggest that there are systems in the US that support this out of the box (ie just connect generator output to hybrid inverter and set current limits).

Nick

From same question asked on FB a few weeks back:

Sorry to hear you are in this position.
I don't know about petrol generator, however I was told that once battery dies and there is no grid, it will not be able to go back to life. Meaning, all solar will be dead too.
So, do not let battery to go flat, otherwise you may have trouble to revive it without grid.

Well, power back on but gateway not working - ie with grid power, gateway is not supplying any load so lights etc remain off.

The only way to power house is using the gateway bypass.
Recovering from this is not obvious - I've asked Givenergy but so far no response...

Back to the generator response - if the issue is dirty sine wave with high THD and wandering voltage there are generators which invert to DC before outputting as AC and have voltage stabilisation - does anyone know what the THD and voltage tolerance are for the AIO?

So it looks like if I can get a suitably stable supply, I could then use a transfer switch to use generator rather than grid in a power outage.

Perhaps rectify it and feed it into a second PV input if you have one. Not sure that the MPPT algorithm would do though. It might just draw more and more current so the generator would need to be rated higher than the inverter PV max throughput.

ratlake I kid you not but if the AIO goes flat to the point it won't turn on, then it won't tell the gateway to close its relays because it relies on the AIO telling it what to do (which in turn allows the AIO to then charge, and get itself back to being able to switch on) so you get stuck in this weird and very useless state. Not really sure what the solution is to be honest but Giv have to poke and prod it from their end from what I've read.

GE have been unable to start AIO - one of the 4 batteries is at 64V whilst the rest are at 72V and this apparently means the system is below threshold required for BMS to start.
I'm waiting on next level of support to determine what to do.

The rest of the system (PV array and gateway) are working OK.

I also do not have a response from GE about why an inverter generator with a THD of 3% cannot be used (via manual transfer switch) when grid fails.

I did also think of using my existing non-inverter generator to power a battery charger to output 80v/20A DC into one of the PV strings via transfer switch so hybrid inverter thinks it's getting solar and charges battery but can't find any specs on PV string inputs - I think this is what nophead suggested.

Sorry to hear that. The low Voltage (I.e non AIO batteries) have a procedure to manually force charge the cells directly - bypassing the BMS in this circumstances. I don't doubt similar can be done to the AIO but as far as I know there is no published guide. I'm not entirely sure if you can get to the terminals behind the BMS without some severe dismantling of the battery module.