EV Charger Dedicated Circuit
A 7.4 kW charge point on a circuit of its own: a rotary isolator that can be locked off, an RCBO covering both fault currents, and an earth run straight to the unit.
Components Needed
Text Wiring Path
Live + Neutral → Isolator → RCBO → Charge Point Earth → Charge Point (E)
Schematic
Steps
- 1Place Live, Neutral and Earth terminals.
- 2Place a rotary isolator first in line — it switches both live and neutral for safe maintenance.
- 3Place an RCBO after the isolator, then the charge point as the load.
- 4Wire Live and Neutral through the isolator into the RCBO, then out to the charger.
- 5Run Earth straight to the charger's E terminal, bypassing both devices.
- 6Press Run, then open the isolator: the whole charge point goes dead while its earth stays connected.
A charger is a sustained high load, so it gets a dedicated circuit rather than a spur off a ring. The isolator exists for maintenance, the RCBO covers overcurrent and earth leakage, and the RCD type matters — smooth DC leakage from a vehicle can blind a Type AC device.
A charge point is a continuous high load on a dedicated circuit. It needs the right earthing arrangement for the supply (TN-S, TN-C-S or TT) before any vehicle is connected, and the RCD type the manufacturer specifies — household Type AC devices can be blinded by smooth DC leakage.
Terms used here
Defined in the glossary — each one opens at its own entry.
Now wire it for real.
Build this circuit in the browser, inject a fault, and watch the protection respond.