An RCD that trips while your EV charges is doing the job it was installed for: it has detected earth leakage beyond what it is designed to allow, and cut the power. EV charging can produce that trip honestly — small leakages add up across an installation, vehicles leak a little by design, and a car’s DC leakage behaviour can defeat some RCD types. When it trips is the evidence that tells an electrician which layer to check.
Key Takeaways
- An RCD trip during charging is protection working: it has found earth leakage beyond its allowance.
- When it trips — at start, minutes in, wet weather, one car — points to the layer at fault.
- Whether the RCD type suits EV duty is an electrician’s design question, never a DIY swap.
- No EVDANCE listing states a built-in RCD; get the manual’s upstream requirement in writing.
What the RCD Is Watching
An RCD compares the current leaving on the live conductor with the current returning on the neutral. Any difference is leaking somewhere it should not — through a fault, moisture, or a person. The device trips before that leakage becomes a shock.
EV charging adds two wrinkles. A charging car runs for hours, so small leakages elsewhere on the same device have hours to matter. And a car’s onboard charger can produce smooth DC leakage, which some RCD types cannot sense correctly. Our guide to RCD protection for EV chargers explains those types — Type A, Type B and 6 mA DC detection — in full. Protection for an EV circuit is a property of the installation design: the charger’s manual states what upstream device it requires.
Read the Pattern Before Anyone Touches Anything
| When it trips | Layer it points to | First response |
|---|---|---|
| The moment charging starts | The vehicle or charger is leaking beyond the device’s allowance — or the fitted RCD type does not suit EV duty | Note whether a second car changes anything; then an electrician, pattern in hand |
| Minutes into every session | Cumulative leakage: small leakages across circuits share one device; charging crosses its limit | An electrician maps what else the device protects |
| Only in wet weather | Moisture in an outdoor socket, junction or the car’s inlet gives leakage a path | Stop using the wet point; an electrician inspects |
| Only with one car | That vehicle’s own leakage behaviour, or its inlet’s condition | The car’s maker is part of the answer — tell the electrician which car |
| With no car connected at all | The fault is in the installation, not in the charging | An electrician — the charger is not the suspect |
The pattern costs nothing to collect, and it puts the electrician several steps ahead on arrival. The charger’s own ground-fault message is a different event from the board’s RCD letting go: the message is the unit reporting, the trip is the installation acting. Our driver’s checklist for a charger that is not working separates the two.
The RCD Type Is a Design Question, Not a Swap
Whether a circuit needs Type A, Type B or a dedicated EV device is set by the charger maker’s stated requirement and the local code — in the UK, the IET Code of Practice is the installers’ reference. If the fitted device is the wrong type for EV duty, the correction is the electrician’s to design. It is never a do-it-yourself exchange: changing the type or sensitivity changes the protection design for every circuit the device covers, and a “less sensitive” RCD fitted to stop trips removes protection without fixing a real leak.
What the EVDANCE Range States — and What to Ask in Writing
The EV-ACT3204PE is a 22 kW three-phase wallbox with a tethered Type 2 cable, RFID and app control, and CE marking. The EV-ACS3210E is a 32 A Type 2 portable charger at about 7 kW single-phase, IP66. Neither product page states a built-in RCD or names the upstream RCD type — the requirement comes from the manual and your electrician’s design, worth having in writing before installation. Specifying a circuit? Ask us for the manual’s requirement.
Frequently Asked Questions
Is a tripping RCD dangerous?
The trip itself is the safe outcome — power is cut. The leakage behind it needs finding. Do not keep resetting to finish a charge; a repeating trip is an electrician call.
Can I change the RCD for a less sensitive one myself?
No. Type and sensitivity are the protection design; changing either is an electrician’s decision under the local code. A less sensitive device stops trips by stopping protection.
My circuit also trips the breaker with the overload. Is that the same fault?
Not necessarily. An overcurrent trip and an earth-leakage trip are different devices answering different questions; some units combine them. Our guide to why an EV charger keeps tripping the breaker covers the overcurrent side; a combined pattern is what to hand to the electrician.
Related Reading
- RCD Protection for EV Chargers: Type A, Type B and 6 mA DC Detection Explained
- Does an EV Charger Need GFCI Protection?
- Why Does My EV Charger Keep Tripping the Breaker?
- Why Is My Electric Car Charger Not Working? A Driver’s Checklist
