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ESP32 PV Divert question

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Have a question regarding the Solar PV Divert on the ESP32. Just got solar so I have been itching to try this out. I noticed that when no vehicle is plugged and solar excess is available the charger screen will flick to green and back to standby. When it’s plugged into the vehicle, if the vehicle has a hold on charging due to TOU programming (charge time starts at 2100 hrs) then each time the PC Divert calculates a charge rate change the vehicle acts like it was just plugged in before stopping the charge due to it’s hold.

It’s like each time the PV Divert calculates a new charge rate it’s resetting itself when it changes the pulse width. I’m wondering if that is the case.

What happens when you tell the car to charge and ignore any schedules. As the EVSE cant force a car to charge

Same effect. I believe the EV is simply testing the connection and charge rate being reported by the EVSE.


what MQTT feed are you using to tell the EVSE there is solar excess?


My PV reading taken from the PV panel and my house feed is taken from the mains. So best description is Type 1. Both are read by IotaWatt.

Attached is the input setup for them, but I have a feed called SolarExcess that is sent to the OpenEVSE units.

Here is the solar input.

So the solar is summed together to get the total solar output which is then fed to an MQTT feed.

Here is the complete math work under the house mains.

Then from the mains input the total about is subtracted from what the solar generation to get either the excess solar available or if none is available. That is sent to an MQTT feed which is what is sent to the OpenEVSE.

I’m just finding that for some reason, even though the charger doesn’t have excess PV, it is setting the max current to 6A and keeps it at that even when timer override occurs at night.


I can see why it is not working, the feed to your EVSE “solarexcess” needs to be negative so your figure of 2696 needs to be -2696 then it will all work OK.
This is my feed


Oh, at the time I took the screen capture my solar wasn’t on. Was awaiting my net meter to be installed. It’s on now and divert is working. My issue is with at night the timer over ride occurring and defaulting to 6A instead of the 40A max allowed. It appears this over rides the max A setting. Which actually is a problem since that max A setting is also a check to ensure the charger doesn’t attempt to use more than what the breaker allows.