| Problem | Likely Fix | |--------|-------------| | Reflash.exe can’t open COM port | Close all monitoring software (WatchPower, ICC, SolarAssistant). | | Stuck at 0% | Wrong cable (needs genuine RS-232, not null modem). | | Inverter shows Err 32 after flash | Reflash again – incomplete firmware. | | No display after flash | Reflash U2 (display firmware) using a different COM port baud rate (try 2400). |
Controls the power conversion, MPPT tracker, inverter stages, and general system logic.
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.
Follow these steps exactly to ensure a safe installation. Interrupting the process can permanently damage the control board. Step 1: Isolate the Inverter Turn off the inverter inverter switch. Disconnect the AC input source. Disconnect the PV (solar) input array. Keep the battery connected to provide stable control power. Step 2: Establish the Data Connection
: The inverter switches to float charge mode too early, preventing batteries from reaching full charge. The display may show float voltage immediately rather than reaching bulk voltage levels. axpert vm iii firmware
: Once finished, restart the unit and check the version number on the display or via WatchPower. Important Model Distinctions
Inside the flashing tool, select the correct COM port identified in step one. Set the baud rate according to the firmware release notes, which is typically set to 9600 or 19200. 4. Initiate the Flash
If you own an Axpert VM III parallel kit (up to 9 units), firmware maintenance is critical:
. If a triangle icon appears, the USB-to-serial driver is not correctly installed. 2. Required Software & Tools | Problem | Likely Fix | |--------|-------------| | Reflash
Look for the screen displaying followed by a number (e.g., U1 91.20). This represents your Main CPU firmware version .
Upgrading the firmware requires a stable Windows computer and a direct physical data connection to the inverter. Do not attempt an upgrade using a virtual machine or over an unstable Bluetooth connection. Prerequisites & Equipment Needed: A laptop or PC running .
The inverter will automatically reboot. Disconnect the data cable and verify your new firmware version using the LCD screen navigation keys. Troubleshooting Common Flashing Errors
Some older versions had aggressive fan profiles. Updates often optimize cooling to reduce noise while maintaining safety. | | No display after flash | Reflash
Manages the detachable LCD screen, button inputs, LED indicators, Wi-Fi/Bluetooth modules, and external BMS communications.
Optimizes Maximum Power Point Tracking (MPPT) efficiency for better solar yield.
What are you connecting to the inverter?