Open EVSE and solar divert running alongside a hot water solar divert

Hi, I’m looking at replacing my EV charger with a charger that is capable of tracking my surplus solar PV. I have a diverter to heat my hot water at the moment. Has anyone managed to make open EVSE have priority over the hot water diverter?

My energie’s Zappi has the capability by placing a ct clamp before the diverter.

As Open EVSE uses the surplus calculation from the emonpi I assume you would need an additonal ct clamp.

If you put the Zappi current clamp on the PV feed and leave the solar hot water diverter on the main supply tail, then it will work in the required way.

The OpenEVSE will take priority over the hot water diveter if you use the ‘Solar PV Gen topic’ from the emonPi rather than the grid export feed. This will mean the OpenEVSE will divert the total amount of solar generation rather than the excess, however compared to the amount of energy used in most homes your EV will probably be consuming more than your house consumption, therfore EV taking priority is usually preferable. Thye OpenEVSE will not start charging until the PV is producing at least 1.4kW (6A) which is the lowest current an EV can charge at.

See :GitHub - OpenEVSE/ESP8266_WiFi_v2.x: ESP8266 WiFi for OpenEVSE Version 2.x