question

It is always good to test these things. These are my thoughts, they might be wrong.

I disagree with your final point. Once you program an assistant to control ACout2, the normal function of ACin enables ACout2 does not apply anymore.

It is possible to bring this back with another assistant (that is higher in the logic order of the list), or depending on the behaviour you want by using the final configuration setting of the generator assistant.

The generator is stopped when AC1 is available + logic inverted = AC2out relay is closed and water is heating when shore power is available.

This presumes you want to continue heating hot water when shore power is connected, and other conditions are met.

If you want the hot water to immediately heat whenever shore power is connected:

I would add 2 additional programmable relay assistants, one to Use ACout2 relay on when AC input is available for 10 seconds. And the other to Use ACout2 relay off when AC input is not available for 10 seconds.

I would have to think a bit harder about what order they need to go in the logic.

So please test it though, make sure it is behaving like you expect and report back. I still learn something every time I set up a real world assistant application.

I have tested it need to work on voltage cut offs due to voltage sag, I added a couple wires down from the battery sense terminal so I hope that will also help with voltage sag and dialling in cut offs.

looks like a very complicated way to do a simple function.

If you are using a Victron MPPT solar controller then use its built in programmable relay function.

Best way is to set it for battery float state - the energy dumps into hot water wherever the batteries are floating.

The hysteresis is handled by the "minimum time" period function.

See Victron MPPT Solar Charge Controller manual pages 18 + 19.

I have to be honest the cycling when off grid of the battery kind of annoyed me, especially when I was in hot areas like 45 degree C I really didn't need the hot water, actually I turned it off to use the hot water system like a cold water tank and the tanks under my bus were heated by the road. I found manually cycling the power to the hot water was less demanding on the battery and I did not have to deal with the inverter revving up in the middle of the night to heat water I did not need hot. I didn't plug into shore power for over a year.

When you get the bluetooth models in the future a pre programmed function for this would be useful.

I still have a function programmed for this circuit and that's I am using too much power eg cooking dinner on the induction cooker on 3 (out of 9 settings) I can have the hot water heating too, but if punch the inverter to 9 (2000W technically) the inverter is not going to take to take that and the 1500W heating elements so it cycles the hot water off, until I realise and turn the induction cooker down, I would be burning things at 9 anyways just a quick pre heat of the pan. 18 months now off grid with the magic blue box, happy customer.