What is this?
EV chargers draw significant current (typically 7.2kW, or 32A on a single phase) and have built-in earth leakage protection. When an EV charger trips the electrics, it could be the charger's internal protection, the consumer unit's RCD or RCBO, or both. This is a relatively common issue and needs professional diagnosis.
Common causes
- Earth leakage from the charger exceeding the RCD threshold
- DC fault current — some EV chargers produce small DC leakage that trips Type A RCDs
- Faulty charging cable or connector
- Moisture ingress into the charger or its connections
- Vehicle-side charging fault causing earth leakage
- Incorrect consumer unit protection — wrong RCD type for EV charging
Is it dangerous?
The tripping is a safety mechanism working correctly. Do not bypass or uprate the protection. If the charger trips every time, there is a genuine fault that needs finding. Repeatedly resetting and attempting to charge without investigation could mask a serious issue.
Can I fix it myself?
Check if the charger trips immediately when plugged into the car or only during charging (which can take a few seconds to start). This helps the electrician diagnose the fault. Check the charging cable and connector for damage, dirt, or moisture. Make sure the charger connector is fully seated in the car. If it only trips in wet weather, moisture ingress is likely.
When to call an electrician
Call an electrician if the charger trips every time or intermittently, if the trip affects other circuits in your home via the main RCD, if the charger was recently installed, or if the problem started after any changes to your consumer unit.
What will an electrician do?
Test the EV charger circuit and its protective devices
Measure earth leakage current during a charging session
Check the type of RCD protection — upgrade to Type A or Type B if needed
Inspect the charger for moisture ingress or connection faults
Test with a different vehicle if possible to isolate charger vs vehicle faults
Replace the RCD/RCBO with the correct type if the original is incompatible
Typical cost
£100 – £350
RCD or RCBO upgrades are common and cost around £100-£200. If the charger itself is faulty, warranty replacement may apply. Investigation of intermittent faults may take longer.


