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Manual - EV Charging Station

9. Troubleshooting

In this section:

9.1. CP Line Calibration

What is CP?

CP is the control pilot signal (line) inside each Type2 charger connector. It is a bi-directional communication line that enables communication between the charging station and the EV. Among other things, the charging station informs the EV of the maximum charging current available. At the same time, the EV informs the charging station about its status, for example whether the EV is connected or whether it is currently charging.

Why is CP line calibration necessary?

Due to differences in cable length and manufacturer as well as deviations in the ratings of electronic components, the CP signal may show deviations. The CP calibration takes the signal deviation into account and adjusts the signal values to the required ranges.

When does the calibration of the CP line have to be carried out?

There are several reasons for a CP line calibration. The most important are:

  • The EV is connected to the EVCS via the charging cable, but still reports a disconnected state

  • When charging the EV, the EVCS frequently switches between the 'charging' and 'charged' states

  • The EVCS does not start charging after connecting the vehicle because it cannot detect the correct state after connection

How is a CP line calibration carried out?

The CP calibration can be done via the web interface (Settings → General → Charger → CP calibration or via VictronConnect (Settings page). The procedure is as follows:

  1. Press the calibration button

  2. Connect the EV to the EVCS and then tap on Next in VictronConnect

  3. Press the 'Vehicle is connected' button to confirm that the EV is indeed connected to the EVCS (or tap on Next in VictronConnect)

  4. Wait until the EVCS has completed the calculation

    Once the calibration is complete, a message is displayed indicating that the calibration was successful


9.2. Frequently asked questions

9.2.1. Q1: How do I prevent the charging station from being used by unauthorised persons?

Make sure EV charger autostart is disabled in general settings. This prevents the charging station from starting to charge automatically once it is connected to an EV.

Also ensure the Lock charger display setting on the general tab of the web interface or in the Remote console of the GX device is enabled.

Charging can then only be started or stopped via the web interface, VRM App widget, VRM controls and VictronConnect.

9.2.2. Q2: Does the EV Charging Station have RFID?

No. To prevent the charging station from being used by unauthorised persons, see Q1.

9.2.3. Q3: The light ring is annoying my neighbours during night, how can I disable the light ring?

You can completely disable the light ring in the light ring menu, changing the brightness to 0 or a lower level if you like.

9.2.4. Q4: Why isn't my car recognized when I connect the charging cable?

Try calibrating the CP line (general tab in the web interface or in the VictronConnect settings). This is sometimes necessary because the charging cables can differ slightly. Ground impedance is also important as all measurements are relative to ground (GND).

9.2.5. Q5: Why does my EV Charging Station show up on multiple GX devices?

If there are several GX devices on the same local network, activate the IP address whitelist in the General tab of the web interface and then add only the IP address of the GX device with which the EVCS is to be controlled to the whitelist. After doing this, remove the EVCS from the other GX devices.

9.2.6. Q6: How much PV power do I need at least to charge the EV in automatic mode?

The minimum current for charging an EV is 6A@230V. You therefore need more than 1.3kW.

However, this may not be sufficient under certain circumstances, e.g. if AC loads are still being supplied at the same time. Charging only takes place if there is enough excess solar power, which is calculated as follows:

Excess solar power = Total PV production - AC loads (without car consumption) = 1380W (230V x 6A)

Note that there are EVs that require an even higher minimum charging current, e.g. the Renault Zoe; 10A, which further increases the minimum PV power required.

9.2.7. Q7: Is it possible to operate multiple EV Charging Stations in one system?

Yes, this is possible. The available power is then shared between them.

9.2.8. Q8: The EV is fully charged, but the EVCS still alternates between start charging and stop charging, why?

The reason is most likely that the EVCS cannot correctly decode the 'charged' signal coming from the EV. Perform the CP line calibration to remedy the problem.

9.2.9. Q9: I keep getting a GX device communication error! The minimum SoC cannot be checked. What is the reason for this?


This error indicates that the EVCS cannot read the SoC from the GX device because there is a communication problem even though communication with the GX device is enabled in the EVCS web interface.

To remedy the problem, make sure that the IP address specified in the general settings of the web interface matches that of the GX device. Use the Discover function to allow the EVCS to derive the correct IP address from the VRM Portal ID - for more details, see the EV Charging Station setup chapter. Also make sure that ModbusTCP is enabled in the GX device itself.

9.2.10. Q10: Is a GX device in the system absolutely necessary?

This depends on the operation mode.

For automatic mode, communication between a GX device and the EVCS is mandatory. For manual and scheduled mode, a GX device can be installed, but does not have to be.

9.2.11. Q11: I would like to control the EVCS via Modbus TCP. Is this possible and if so, how?

Yes, this is possible. Modbus TCP offers a much higher degree of flexibility and control and provides access to a broader range of settings than what is described in the manual or available through the normal user interfaces.


Note that changes to the settings via Modbus TCP will void any support.

The recommended method for support on Modbus-TCP questions is to use the Modifications section on Victron Community. Its frequently visited by many people using Modbus TCP and other methods of integrating with Victron products.

The EVCS Modbus TCP register list can be downloaded from the product page in the download area.

9.3. EVCS Notification, Warning, Alarm and Error Codes

The table below lists all possible warnings, alarms and error codes displayed in VictronConnect, a GX device or the web interface, which can be used for quick diagnosis and help with troubleshooting.


VictronConnect code

GX device code

Generic code






GND not present

Appears when the EVCS detects missing PE.

Contact the installer.




Welded contacts

Appears when the EVCS detects welded contacts of the power relay.

Contact the installer.




CP input short-circuit

Appears when the EVCS detects CP input shorted.

Contact the installer.




Residual current

Appears when the EVCS detects residual current.

Contact the installer.




Over temperature

Appears when the EVCS detects overheating.

Remove EVCS from direct sunlight or contact the installer.


VictronConnect code

GX device code

Generic code






Initial setup not completed

Appears when the initial setup is not finished.

Perform initial setup.




EVCS externally blocked by grid operator

Appears when EVCS is locked externally by the grid operator.

Contact your grid operator.




EVCS high temperature detected

Appears when a high temperature is detected in the EVCS box, but the temperature is not yet critical to stop charging.

Remove EVCS from direct sun light or contact installer.




GX communication warning

Appears when communication with GX is enabled but not present.

Check GX device IP address and VRM portal ID configuration.




Overload detected

Appears when EVCS detects overload.




Overload active

Appears when EVCS detects overload and it is active.




Scheduled mode failed - time sync issue

Appears when EVCS can’t synchronise the local date/time and the user switches to scheduled mode.


VictronConnect code

GX device code

Generic code






Auto mode not available

Appears when attempting to set Auto mode but GX communication is disabled.

Enable communication with GX device.




Scheduled mode not configured

Appears when trying to set Scheduled mode but the scheduler is not yet configured.

Add configuration for Scheduled mode.




Car disconnected - can't start charging

Appears when the 'Start' button is pressed but the car is not connected to EVCS.

Connect the car.




Charger error

Appears when the 'Start' button is pressed but the EVCS has an error.

Check errors and resolve them; contact the installer.




Initial setup not completed

Appears when the 'Start' button is pressed but the EVCS initial setup procedure is not finished yet.

Perform initial setup.




Charging will start according to scheduler settings

Appears when the 'Start' button is pressed but the EVCS is in Scheduled mode.

Switch mode to ‘Manual’ if you want to control charging.




Overload active - can't start charging

Appears when the 'Start' button is pressed but an overload is active.