Lost in the hardware revisions

Hi all,

I have two OpenEVSE Advanced Series - 48A/40A/32A Kits here, purchased from the US in May 2019.
I recently purchased two OpenEVSE Wifi kit (ESP32 based) upgrades to replace the original ESP8266 boards. The OpenEVSE controllers are running firmware 5.0.1 EU.

Is it possible to upgrade these to run 7.1.3 or later to make them compatible with the latest wifi firmware for the ESP32 (see below)? I don’t know which hardware revision these boards are; they look different from the (discontinued?) v4 boards.

The cables supplied with the new OpenEVSE Wifi kit suggest that the wifi board is powered directly from the 12VDC on the OpenEVSE controller (the power wires are bare). It would surprise me though if those boards are not 5VDC. This would suggest that the supplied cables are not “plug & play” but that some soldering or modification is required to use the DC/DC converter that was powering the old ESP8266 board. No problem, but the original kit was supplied "plug & play / no worries, all clear’ so now I’m not sure…

Unfortunately the kit was not supplied with a wiring diagram or guide how to replace the ESP8266 module wiring wise with the ESP32 module.

I’ve emailed the folks in the US a couple of times but it seems they are overwhelmed / overworked.

Your help is much appreciated.


Yes you should be able to update the OpenEVSE firmware to the latest. Most of the resent changes are to the connectors and have no impact on the firmware.

With regard to the WiFi module, this is designed to be powered from the 12v output of the EVSE board it has an on-board DC to DC converter, so if you have an external 12v to 5v DC to DC converter, you can also remove that.

Hi Jeremy,

Many thanks for your help. I now have a modified D8.2.0 (max current 15A due to Gen 1 Nissan Leaf charger issue) firmware running on the controller talking happily to 4.1.2 running on the ESP32. :smiley:

Best regards,