Axpert — Vm Iii Firmware
Once the tool says "Update Successful," the inverter will restart. Re-check the U1/U2 screens to confirm the new version. Critical Safety Warning
represents the MCU (Remote Display/Bluetooth panel) firmware.
Newer firmware versions often include improved protocols for communicating with Pylontech, Dyness, and other popular lithium batteries via the RS485 or CAN port. axpert vm iii firmware
Press the or DOWN buttons until you see the screen showing "U1" followed by a number (e.g., U1 41 02 ). U1 represents the Main CPU (Inverter) firmware.
There are different "hardware flavors" of the VM III (e.g., 1.5kW, 3kW, and 5kW models). Flashing a 5kW firmware onto a 3kW unit will cause a permanent hardware mismatch error. Always verify that the firmware version matches your specific rated power and original firmware branch . Troubleshooting Common Issues Once the tool says "Update Successful," the inverter
Everything You Need to Know About Axpert VM III Firmware Updates
Try a different USB cable or a different laptop. Inverters are notoriously picky about Serial-to-USB chipsets (FTDI chips are recommended). Newer firmware versions often include improved protocols for
Click "Update." The inverter fans may spin up, and the screen might go blank or show "UP."
Ensure you aren't running WatchPower or any other monitoring software in the background. They "lock" the COM port.