How to Perform Victron Remote Firmware Updates via VRM Portal

Updated 6 September 2026 · By SolarNevs Research Desk, Dealer surveys + verified sources · 1 source · Method ↗

Key Takeaways

Remote firmware updates for Victron inverters and inverter/chargers require specific Venus OS and VE.Bus firmware versions.
The most common cause of update failure is not meeting prerequisites, such as having a VE.Bus BMS or DMC connected.
Always ensure your GX device is not powered by the inverter's AC output before starting an update to prevent system unreachability.
If the inverter is left off in bootloader mode or the system becomes unreachable, contact a qualified Victron technician.

How to Perform Remote Firmware Updates on Victron VE.Bus Devices

Victron Energy allows remote firmware updates for its inverters and inverter/chargers, such as MultiPlus and Quattro models. This feature uses the VRM Portal and a connected GX device to update the VE.Bus system without requiring onsite presence. Understanding the prerequisites and process helps ensure a successful update.

Prerequisites for Victron Remote Firmware Updates

Before attempting a remote firmware update, ensure your system meets the following requirements. Failure to meet these can lead to update failures or system issues.

GX Device Connection: The system must have a GX device (e.g., Cerbo GX, Venus GX, Color Control GX) installed and connected to the internet, actively communicating with the VRM Portal.

- For a Color Control GX (CCGX), it must have serial number HQ1707 or newer. Other GX devices do not have a minimum hardware version requirement.

Venus OS Firmware Version: The GX device must be running Venus OS firmware version 2.65 or later.
VE.Bus Firmware Version: The minimum already installed VE.Bus firmware version on your inverter or inverter/charger must be 426 or later.
VRM Portal Access Setting: On your GX device, navigate to Settings -> VRM Online Portal -> VRM Portal and ensure the ''Full'' access setting is enabled.
Connected Devices: There must be no VE.Bus BMS connected to the VE.Bus network. Additionally, no Digital Multi Control (DMC) panel should be connected. These devices must be temporarily unplugged from the VE.Bus network before starting the update.
GX Device Power Source: Be certain that the GX device is not powered by the inverter's AC output. If it is, attempting an update will leave the inverter off in bootloader mode, and the system will become unreachable as the GX device powers down.
AC-Coupled PV Inverters: To prevent overcharging during the update process, disable any AC-Coupled PV Inverters. This can be done by switching them off or performing the update when solar input is minimal, such as after sunset.

Troubleshooting Remote Firmware Update Errors

If you encounter issues during a remote firmware update, the following table lists common error codes and their solutions.

Symptom detail	Likely cause	Fix
Error 734: Cannot update with DMC or VE.Bus BMS connected	VE.Bus BMS or Digital Multi Control (DMC) panel connected to VE.Bus network.	Temporarily unplug the RJ-45 connection on the VE.Bus BMS and/or DMC.
Error 733: Failed to start Update. Incompatible version number.	Venus OS version is too old.	Update your Venus OS version to the latest available version.
Error 733: The bootblock is incompatible this version of the updater.	Venus OS version is too old.	Update your Venus OS version to the latest available version.
Error 733: One or more firmware file(s) supplied do not match the connected device models.	Incorrect firmware file selected for the connected devices.	Ensure you have selected the correct firmware file for your specific Victron device models.
Error 733: The supplied firmware is below the minimum allowed firmware version.	Attempting to downgrade to an older, unsupported firmware version.	Do not attempt to downgrade to this firmware version; the system rejects it.
Error 1342: Not updatable (minimum installed firmware < 426 or CCGX hardware too old)	Installed VE.Bus firmware is older than 426, or Color Control GX (CCGX) serial number is older than HQ1707.	Check that the installed VE.Bus firmware version is 426 or newer. If using a CCGX, ensure its serial number is HQ1707 or newer.
VEConfigure tools File corrupt error	VEConfigure Tools are not the latest version or the file was opened incorrectly.	Double-click the file to open it. Ensure you have the latest VEConfigure Tools installed, which automatically updates when connected to the internet.
mk2vsc-45: Uploaded file does not contain settings data for the connected unit	The settings file was made for a different unit (different serial number).	Ensure the uploaded settings file corresponds to the unique serial number of the target inverter/charger.
mk2vsc-46: Uploaded file does not match model and/or installed firmware version	The settings file does not match the system's full seven-digit model number or firmware version.	Ensure the full seven-digit number in the settings file matches the system. Do not use settings from a different kVA model or firmware version without merging.
mk2vsc-47: More than one unknown unit detected	Applies to multi-unit systems (parallel, split-phase, three-phase) where units are not properly configured.	Go onsite and use VE.Bus Quick Configure or VE.Bus System Configurator to reconfigure the system.
mk2vsc-48: Updating a single unit with another unit's settings is not possible	Attempting to apply settings from one unit to another, even if of the same type.	Perform a Remote VEConfigure download for the target system, then use "Load settings" in VEConfigure to import settings from another file.
mk2vsc-55: File section not found (during firmware update)	Something went wrong during Stage 1 (e.g., VRM lost connection) or the uploaded file is for a different product type.	If due to connection loss, recover old settings using the merge function. If due to product mismatch, ensure the uploaded file matches the product type and model number.
mk2vsc-59: File uploaded before merging in VE.Bus System Configurator	The settings template (.RVMS file) was uploaded directly without processing it in VE.Bus System Configurator.	Open the settings template (.RVMS file) in VE.Bus System Configurator, allow it to process, save by closing VEConfigure, then upload the resulting `_merged.rvms` file.
Remote firmware update fails	Minimum installed VE.Bus firmware version is below 426.	Update VE.Bus firmware to version 426 or later.
Remote firmware update fails	VE.Bus BMS connected to the VE.Bus network.	Disconnect the VE.Bus BMS.
Remote firmware update fails	Digital Multi Control (DMC) panel connected to the VE.Bus network.	Disconnect the DMC panel.
Remote firmware update fails	Color Control GX (CCGX) serial number is older than HQ1707.	Replace CCGX with a newer unit or another GX device, or update onsite.
Remote firmware update fails	Venus OS firmware is older than 2.65.	Update Venus OS to version 2.65 or later.
Remote firmware update fails	"Full" access setting not enabled on GX device.	Enable the "Full" access setting in the GX device's VRM Online Portal menu.
Overcharging occurs during update	AC-Coupled PV Inverters not disabled.	Disable AC-Coupled PV Inverters before starting the update.
Inverter off in bootloader mode, system unreachable	GX Device powered by the inverter's AC output.	Ensure the GX Device is powered independently of the inverter's AC output.
Old settings not restored after update	Internet connection lost during Stage 2 (converting/restoring configuration).	Ensure a stable internet connection throughout the entire update process.

Step-by-Step Guide to Remote VE.Bus Firmware Updates

The remote firmware update process involves two main stages: updating the firmware and then restoring the system's configuration.

Stage 1: Firmware Update

Initiate Update: From the VRM Portal, navigate to your device list and select the option to update the firmware for your VE.Bus device.
Firmware Upload: The new firmware file is uploaded to the GX device.
Configuration Retrieval: The current configuration is retrieved from the VE.Bus system.
Inverter Shutdown: The inverter is switched off.
Firmware Installation: The new firmware is installed on the inverter/charger.
Inverter Restart: The inverter is switched on with default settings. To prevent overcharging, all charge voltages are set to the nominal battery voltage (12V, 24V, or 48V). A settings template (.RVMS file) is saved to your download folder during this procedure.

Stage 2: Settings Restoration

After the firmware is updated, you must restore your original system settings.

Download VEConfigure Tools: Ensure you have the latest version of VEConfigure Tools installed on your computer. If connected to the internet, VEConfigure or VE.Bus System Configurator will automatically check for and apply updates.
Convert Settings Template: Locate the .RVMS settings template file saved during Stage 1. Double-click this file to open it with VE.Bus System Configurator. Allow the tool to process the file.
Save Merged File: Close VEConfigure. This action saves the converted settings file, typically named with a _merged.rvms suffix.
Upload Settings: Go back to the VRM Portal, navigate to Device List -> Remote VEConfigure, and use the 'Upload' function to upload the _merged.rvms file. This will restore your system's original configuration.

Safety Considerations for Remote Firmware Updates

Performing remote firmware updates involves critical components of your solar power system. Observe the following safety precautions:

Understand the Process: The inverter/charger is the core of a Victron power system. Fully understand each step of the update process before proceeding.
GX Device Power: Be 100% sure that the GX Device is not powered by the inverter's AC output. If the GX device loses power during the update, the inverter may be left in an inoperable state, requiring an onsite visit to recover. You can test this by switching the inverter off and verifying that the GX device remains powered.
AC-Coupled PV Inverters: To prevent overcharging, disable any AC-Coupled PV Inverters or perform the update when solar production is absent.

When to call a technician instead

While remote firmware updates are designed for convenience, certain situations warrant professional assistance:

Persistent Errors: If you encounter error codes that you cannot resolve using the troubleshooting table, or if errors persist after following the recommended fixes.
System Unreachability: If the inverter is left off in bootloader mode, all LEDs are flashing, and the system becomes unreachable through the VRM Portal.
Uncertainty: If you are unsure about any step in the process, especially regarding power connections or disconnecting critical components like the VE.Bus BMS.
Multi-Unit Systems: For complex parallel, split-phase, or three-phase systems that report errors like "More than one unknown unit detected" (mk2vsc-47), onsite configuration may be required.

Frequently asked questions

What Victron devices can be updated remotely?

Victron inverter and inverter/charger models, including MultiPlus and Quattro, can be updated remotely. This feature applies to systems with a GX device installed and connected to the VRM Portal.

What is the minimum Venus OS version required for remote updates?

Venus OS firmware must be version 2.65 or later for remote firmware updates to function correctly.

What is the minimum VE.Bus firmware version required for remote updates?

The minimum already installed VE.Bus firmware version must be 426 or later for remote updates to proceed.

Why do I get Error 734 during a Victron remote firmware update?

Error 734, 'Cannot update with DMC or VE.Bus BMS connected,' indicates that a VE.Bus BMS or Digital Multi Control (DMC) panel is connected to the VE.Bus network. These must be temporarily unplugged.

What happens to charge settings after a remote firmware update?

After the firmware update, all charge voltages are set to the nominal battery voltage (12V, 24V, or 48V) to prevent overcharging. The original settings must be restored in a subsequent step.

References

Victron Energy Remote VE.Bus Firmware Updates Manual — accessed 23 August 2026