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Questions about EmonEVSE

Hi all,

Hopefully I have this in the right forum :slight_smile:

Looking at one of these charging stations for my car and I have a few questions in advance:

  1. I do not have an emonPI setup but I can get live grid values sent via mqtt from Home Assistant (value goes into the minus when exporting to grid), can I simply use this for the “eco” charging i.e. charge only when there is excess solar power being generated.
  2. Does the charging pause when there is no excess power? Otherwise it will drain my house DC battery to charge the car which is not efficient.
  3. My car can only charge up to 16a, can that limit value be set somewhere on the emonEVSE? The reason I ask is because I would like to use the existing cable/rcbo going to the current “dumb charger”.
  4. Does the station “lock” the cable in place when charging?

Hi, thanks for your interest. I will do my best to answer your questions:

Yes, no problem to use any MQTT source for the grid excess or solar PV data. Ideally you would want the data to update every 10s or so to ensure the EVSE accurately tracks the solar / grid excess.

Yes it will. See here for more detailed info on how the solar PV divert (EcoMode) feature works: GitHub - OpenEVSE/ESP32_WiFi_V4.x: OpenEVSE V3 WiFi gateway using ESP32

Yes, you can set the maximum current in the UI. However, if you want we can set a hard limit in firmware which is impossible to override via the UI or API which is the safest option.

No it doesn’t, we are currently working on adding this feature. We will eventually be making it available as an ‘add-on’ module to existing units. However, the cable will be locked at the car end so the cable is secure.