question

Hi @usernamepasswordbs ,

What you need is to turn the HWC on when your SoC goes above a certain level and turn it off when you SoC goes below a certain level. These levels depend on your needs. And of course this is not taking into account any other loads there may be on the system.

If you have a device running VenusOS, you can easily do that with a suitable wireless relay (for example with a Shelly (https://www.shelly.cloud/en-us). It might need some custom programming if you'd be up for that.

I haven't used the assistants in the Multi, but I would not be suprised if it possible to program a relay in the Multi based on SoC. I also don't know what the rating of the relay in the Multi is - so you'd need to check that before you start driving a 2KW or so HWC element: maybe you need to use the relay in the Multi to drive a relay that switches the HWC on & off.

Jan

The power electrical side of things is not too much of a problem, it's how to make it as automated and efficient to my needs as possible by using what's already available in the Victron blue boxes. It was just that I wanted to use something other than SoC so the batts can live as long as possible. I can envisage a situation where the batts never achieve 100% charge as the hot water would always stop that from happening in normal use, so, is there a 'thing' that can activate a relay, either in the MPPT RS or the Multiplus, that triggers whenever the MPPT is reducing solar output?

@usernamepasswordbs Do you know you can use the relay to turn on a load when the mppt has reached "float or storage" state?

Look at the demo feature in Victron Connect.

Thanks for that info. i'm not at home at the moment and I can't get Victron Connect to work but can you give me a couple of pointers to finding that setting? It would be much appreciated.

Thanks, got it.