How to Fix / Troubleshooting

Safety first: Turn off power to the Wallbox and external meter before adjusting CTs or wiring.

Verify meter model: Confirm that the external meter is a Wallbox‑approved model and is configured for the correct protocol and baud rate.
Check CT orientation: Ensure that CT clamps are installed on the correct conductors and oriented according to the arrows (toward the load or source as specified). Incorrect orientation can cause negative or zero readings.
Inspect RS‑485 wiring: Confirm that A/B lines are correctly connected between the meter and Wallbox, with proper termination resistors if required.
Check meter address: In the meter settings, verify that the Modbus address matches the value configured in the Wallbox app or installer menu.
Test without meter: Temporarily disable dynamic load management in the Wallbox configuration and see if Error 18 clears. If so, the issue is with the meter or CTs.

Correct wiring and configuration usually resolve this error. If not, replace the external meter or consult Wallbox support.

Wallbox shows 'Error 18'; charging is disabled and may be associated with external energy meter or CTs used for dynamic load management.

Possible Causes