Tesla not charging

[ondrom111]

Prestala mi nabijat tesla. Neviem od ktorej verzie, doma velmi nenabijam. Renault zoe a citroen c zero idu, ale tesla uz nie. A este jedna otazka je lepsie urobit verziu ESP32-S2 EVSE DIY ALPHA, alebo je to jedno devkit je nie velmi stabilny.
Dakujem

[nagyrobi]

ESP32-S2 EVSE DIY ALPHA is very good and charges Teslas very reliably. Zero issues.

[dzurikmiroslav]

It depends on what features you need. If you just need a basic charger then it doesn't matter.
You not need to install all the components on the ESP32-S2 EVSE DIY ALPHA if you only need basic functionality (energy meter, socket lock etc.).
I think most of the problems with the Devkit are caused by insufficient USB adapter...

[ondrom111]

Thank you for your reply.

Let me describe my setup a bit more so you can better advise me.

I am currently using the Devkit-based EVSE with only basic features:

• simple current measurement
• 3-phase / 1-phase switching,
• Nextion display,
• Modbus communication with Home Assistant via an RS485 ↔ LAN converter (USR-DR134).

I don’t use RCM, socket lock or other advanced options, just basic charging with current control and some monitoring.

The main problem I see is that:

• other cars (e.g. Zoe, C-Zero) charge without issues,
• but my Tesla is often more sensitive and sometimes refuses to start or continue charging.

My questions are:

1. Do you think it still makes sense to keep using the Devkit and mainly improve the power supply (better PSU, separate supply for ESP32 vs contactor, bigger capacitors, etc.), or is the Devkit generally too fragile for reliable long-term use with more sensitive cars like Tesla?

2. Would you personally recommend migrating to the ESP32-S2 EVSE DIY ALPHA board instead and only populate the components I really need (meter, CP, relay/contactor, 3f/1f switching, Nextion, RS485/Modbus), and leave the rest unpopulated?

3. If you were in my situation (basic features, Tesla + other EVs, Home Assistant integration), which hardware version would you choose now for a stable “production” wallbox: improved Devkit, or a new ESP32-S2 EVSE DIY ALPHA board?

I’m also wondering if by “insufficient USB adapter” you also indirectly mean that it can cause strange communication behaviour – for example unstable CP signal, random ESP32 resets, or Modbus/Wi-Fi issues that look like communication problems, even though the root cause is actually power. Does that match your experience with the Devkit boards?

Thank you very much for your time and for this project!

[nagyrobi]

1. no idea, never used the DevKit version
2. Use ESP32-S2 EVSE DIY ALPHA with fixed cable (no socket parts installed, and not enabled in the config) see Parts and PCB #52 (reply in thread)
3. ESP32-S2 EVSE DIY ALPHA with HMI based on ESPHome with LVGL. ESPHome will do perfect Home Assistant integration using external component.

From my experience Modbus in Home Assistant is not too reliable, especially not via RS485 ↔ LAN converters. If you don't need a display you can still run ESPHome on an ESP32C3 SuperMini connected via RX/TX UART using AT protocol with EVSE.

Better than LUA imho as it doesn't eat resources of the main EVSE, it will be a separate unit handling this.