Solax inverters

Compatible Solax inverters

• Solax X3 (all revisions)
• Solax X1 (all revisions)

⚠️ Word of caution, CAN overvoltage ⚠️

Solax inverters can burn up CAN chips if there are differences in protective earth. Use the CAN shield pin on LilyGo, and connect it to PE, Also make sure the inverter and battery have a solid connection to protective earth (PE). Failure to do this will lead to the VP231 CAN transceiver chip burning up! 🔥

Word of caution, isolated CAN

⚠️ This inverter does not handle a CAN connected EV battery on the same channel. If the inverter which likes to see only extended CAN frames sees standard automotive CAN frames, the inverter will enter a fault state.

This can be solved in two ways:

• You can use Double Lilygo's
• You can add an isolated MCP2515 CAN channel

ℹ️ The inverter contains a 120 Ohm terminating resistor on CAN-H/L pins

ℹ️ Grounding is extremely important for Solax inverters. Make sure the battery case is connected to protective earth, and the shield part of the twisted pair CAN is connected to PE also! Failing to do this will result in CAN errors.

Compiling the software for Solax inverters

Make sure that the settings in the "USER_SETTINGS.h" file are correct. The line:

#define SOLAX_CAN //Enable this line to emulate a "SolaX Triple Power LFP" over CAN bus

Needs to be uncommented for the software to emulate the Solax protocol over CAN. Next step is then to select the battery that you intend to use, for instance if you use LEAF battery, make sure the following line is uncommented:

#define BATTERY_TYPE_LEAF // See NISSAN-LEAF-BATTERY.h for more LEAF battery settings

After setting this up, flash the board!

Connection diagram

BMS port pin 4 is CAN-H pin 5 CAN-L (for Solax X3 G4).