Solar, emonpi, openevse already installed. How / what to use for hotwater dump

Hardware emonPi
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Solar, emonpi, openevse already installed. How / what to use for hotwater dump?

Electricians on site next week and they are advising an Eddi to divert any excess to the immersion heater.

I’ve read about the Mk2 diverter but I cant get my head around what I need and if its still available. (I see the business is now in france).

Am I right in thinking… As there is already an emonPi controlling the OpenEVSE charging with solar at the property, that it would be best to go for a MK2 and the emonPi would control the Mk2 as well - or - would I need another controller to manage the mk2?

Assuming if the emonPi controls everything then setting up the priorities EV / hotwater would be easier than having an Eddi involved in the mix?

Thank you for anyone that can help

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Robin’s design for the Mk2 PV Router makes it totally self-contained, provided that you monitor the right place.

Although I know the French owners intend to progress the design and move away from through-hole components, unfortunately I don’t know when this is likely to happen or what other changes might be forthcoming.

My guess is your electricians only advise the Eddi because they know about it. If it’s within your area of expertise, you could build your own diverter using an emonTx and a commercial SSR (wired in by the 'tricians), as per the Docs → Learn → PV Diversion.

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Thanks for the speedy response.

The solar runs to the consumer unit in the porch where the incoming main, consumer unit and emonPi are all located. From the way I understand your comment about Mk2 it wouldn’t work unless the immersion is on its own circuit and the Mk2 could also be located on the porch?

Expertise… hmmm - jack of all…
Commercial SSR (solid state relay?) - I’ve no experience of these but are you suggesting that I could use the emonPi to control one (which one?) relatively easily?

Does anyone on here have an eddi, emonpi, openevse with anything to report?

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I have an Eddie and emonpi for a few years now.

I went with the Eddie as it was the only thing offered to me at the time.

The Eddie works fine, I’m now using it with tank with two immersion heaters, but to see what its doing you’ll need some monitoring. you’ll need a harvi so the Eddie knows how much solar excess you have , and a hub so you can connect the Eddie to the net and use their app.

Now all of the above is fine but the myenergi gear does not link to the emonpi (to my knowledge). So in order to get stats on when the immersion heaters are in use and the temps of the cylinder, I purchased a emontx and used ct clips on the heater cables and temp probes into the cylinder and all this goes to the emonpi and to the solar divert app.

Hope this helps

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SSR - yes, Solid State Relay.
“use the emonPi to control one (which one?) relatively easily?” You’d need to send “surplus PV” from somewhere inside the emonPi, presumably emonHub, although that might be too slow to respond - in which case from the analogue front end and the “emon” part - to the SSR. Doable certainly, and equally certainly not easy or straightforward, as you can see from @thedumbterminal has written.