RCDs – Residual Current Devices
Residual Current Devices (RCDs) protect against earth leakage faults and electric shock, making them a core part of every 18th Edition installation. Choose from Type A or Type AC RCDs in 30mA or 100mA sensitivities, or step up to Type B RCDs for DC-sensitive installs like EV and solar.
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All RCDs in this range meet BS EN 61008 and 61009 standards and are suitable for both residential and commercial use. They disconnect supply immediately if leakage is detected, protecting against electric shock and reducing fire risk.
- Type A RCDs – detect AC and pulsed DC leakage, now the UK standard for most new installs
- Type AC RCDs – detect AC leakage only, being phased out in many applications
- 30mA sensitivity – personal protection for final circuits
- 100mA sensitivity – time-delayed or selective protection in larger installs
Need combined overload and leakage protection? View our RCBO range. For shipping details, see our delivery information or returns policy.
2 Pole B Type RCDs
£125.00
The WCED WEV2 Series B-Type RCD provides advanced protection against smooth DC residual fault currents, as well as AC and pulsating DC faults up to 1000Hz. Fully compliant with IEC/EN 62423, it’s the correct choice for EV chargers, solar PV inverters, UPS systems, high-frequency converters,...
4 Pole RCD Type A High Immunity
£22.20
The WCED WAR4 Series 4 Pole Type A High Immunity RCDs are engineered for demanding modern electrical systems where standard Type AC devices fall short. They are particularly suited for: Solar PV arrays – providing stable protection even with inverter-driven circuits. EV charging installations –...
Heat Pump RCD -B Type 2 Pole - WHP240-030
£125.00
The WHP240-030 is a compact Type B RCD specifically designed for heat pump systems - including Vaillant installations where full DC fault protection is required. Unlike Type A or Type AC RCDs, this 2 pole device is engineered to detect smooth DC leakage currents and...
2 Pole RCD Type A High Immunity
£15.26
This 2 Pole Type A RCD offers residual current protection for modern single-phase installations - including solar inverters and EV chargers. Designed with high immunity to nuisance tripping, it detects both AC and pulsating DC leakage currents up to 6mA, making it suitable for today’s...
Heat Pump Consumer Unit - WME**/HP40C
£147.80
This Heat Pump Consumer Unit is a dedicated protection board designed specifically for inverter-driven heat pump circuits. Supplied pre-configured with a 40A Type B RCD, a 40A Type C MCB, and a 2-pole Type 2 SPD, it offers full compliance with BS7671 18th Edition Amendment...
What Is an RCD?
An RCD (Residual Current Device) is a protective switch that cuts power if it detects current leaking to earth. This protects against electric shock and reduces the risk of fire caused by faulty wiring or appliances. Under the 18th Edition Wiring Regulations, RCDs are mandatory on most final circuits in the UK.
Types of RCDs
- Type A – detects both AC and pulsed DC leakage. Recommended for modern appliances, EV chargers, and heat pumps. Example: 2-Pole A-Type 100mA Time Delay RCD.
- Type AC – detects AC leakage only. Still in use but no longer recommended for new domestic installs.
- Type B – DC-sensitive devices for EVs, solar, and heat pumps. See our Type B RCD category.
- Type F – specialist for variable frequency drives and sensitive electronics.
Sensitivity & Ratings
RCDs are available in different ratings to suit their application:
- 30mA – provides personal protection against electric shock, required on most socket and lighting circuits.
- 100mA – typically used for fire protection or selective time-delayed devices in larger installs.
- 300mA+ – used in industrial or commercial systems for equipment/fire protection.
FAQs on RCDs
What’s the difference between an RCD and an RCBO?
An RCD only protects against earth leakage. An RCBO combines RCD and MCB protection in one device.
Are Type AC RCDs still allowed in the UK?
Yes, but Type A RCDs are now strongly preferred under the 18th Edition due to the growing use of electronics and inverter-driven equipment.
How often should RCDs be tested?
They should be tested every 3 months using the “test” button, and formally checked at each EICR or inspection.
Why Buy From Power & Data UK?
All RCDs we supply are BS EN certified, backed by manufacturer warranties, and shipped directly from our UK warehouse. Orders over £30 qualify for free next-day delivery, with optional Saturday upgrades available. Need to send something back? See our returns policy.
Explore Related Categories
- RCBOs – combined protection devices
- High Immunity RCBOs – prevent nuisance trips
- Type B RCDs – DC-sensitive protection
- Circuit Protection – MCBs, RCDs & breakers
- Surge Protection Devices (SPDs)