RCD's

RCDs (residual current devices) are protective switches that trip when they detect current leaking to earth, cutting the supply quickly enough to reduce the risk of fatal electric shock. We carry 30mA 2 pole and 4 pole RCDs from Garo and Live Electrical in ratings from 40A to 100A, a Live Type A high immunity model and a Garo 100mA S Type for time-delayed upstream protection.

Trade customers get trade prices, and stock ordered by 5pm Monday to Friday arrives the next working day throughout Northern Ireland and the Republic.

GCD63-4-03 In-Stock

Garo 63 Amp 30mA 4 Pole RCD

£76.66 inc. VAT

GCD63-2-03 In-Stock

Garo 63 Amp 30mA 2 Pole RCD

£31.20 inc. VAT

RDA240-030 In-Stock

Live Electrical 2 Pole 40A 30mA RCD Type A High Immunity Double Pole RCD

£30.00 inc. VAT

RD2100-030 In-Stock

Live 2 Pole 100Amps 30mA RCD

£25.20 inc. VAT

RD280/030 In-Stock

Live 2 Pole 80Amps 30mA RCD

£24.90 inc. VAT

GCD63-4-1S Ships in 3-5 days

GARO 63A 4 Pole S Type RCD 100ma

£124.82 inc. VAT

Choosing an RCD for your board

An RCD compares the current flowing out on the line conductors with the current returning on the neutral. If the difference exceeds its rated sensitivity, it trips. It does not protect against overload or short circuit, so it is always used alongside MCBs or replaced by RCBOs.

Sensitivity and type

30mA - the usual rating for additional protection of socket outlets, bathrooms and outdoor circuits.
100mA S Type - a time-delayed device, such as the Garo 63A 4 pole, fitted upstream so that a 30mA device downstream trips first (discrimination).
Type A - responds to AC and pulsating DC residual currents, which suits modern electronic loads. High immunity versions are designed to reduce nuisance tripping.

Poles and current rating

Use a 2 pole RCD on single-phase boards and a 4 pole RCD on three phase supplies. The current rating (40A, 63A, 80A or 100A in our range) must cover the combined load of the circuits it feeds and coordinate with the upstream fuse; the RCD itself is not an overcurrent device.

Installation and testing

Fit RCDs to the board manufacturer's instructions and test them with an RCD tester after installation, then periodically using the test button. Check current wiring regulations for where RCD protection is required. For individual circuit protection see our RCBOs, pair split load boards with matching MCBs, and browse electrical testing equipment for RCD testers.

Why order from Meteor Electrical

We stock 5,000+ products from 100+ trade brands at our Cookstown warehouse. Delivery is free over £30 / €35 ex VAT, England, Scotland and Wales receive orders in 3 to 5 working days, and you can call 028 8675 1515 (048 from ROI) between 8am and 5pm on weekdays.

FAQ's Ask Your Own Question

What are RCDs?: Residual Current Device (RCDs) is used to help save lives by preventing electric shocks. RCDs are designed to detect dangers of electric shock causing them to trip and turn off the circuit. RCDs reduce the risk of life threatening injury.
What trips an RCDs?: RCBs trip when there is a fault in the electrical circuit. If your RCD trips frequently, there is a damage in your electrical appliance. This helps you to identify the hazards to prevent electrocution and provide maximum protection.
What does RCDs not protect against?: RCDs are designed to protect against earth leakage currents. However, will not be able to protect against current overload and short circuits. MCDs would be used to protect against overloads and short circuits or RCBOs for protection of both current overload and earth leakage currents.
Can RCDs protect against fire?: RCDs are designed to protect against earth leakage currents. Earth leakage currents can cause fires. Therefore, RCDs are extremely effective and can protect against fire.
Are RCDs required?: RCDs are designed to protect your home and yourself from potential hazards. RCDs are used to identify faults in the electrical circuits to prevent life threatening injury and the hazard of a fire.
How do you know if an RCDs is faulty?: It is important to install RCDs with the correct current rating. If an RCD has a low currenting rating, it can cause it to trip repeatedly.
How to test RCDs?: RCDs must be tested regularly to ensure the device is operating. RCDs are extremely easy to test and are fitted with a test button. Press the test button and release to test if an electricity supply is connected. The test button will identify if the device is operating correctly.
What is the difference between Type AC, Type A and S Type RCDs?: Type AC RCDs detect only sinusoidal AC residual current, while Type A devices also detect pulsating DC, which is common with electronic equipment. S Type (selective) RCDs add a deliberate time delay so a downstream 30mA device can trip first. Check current wiring regulations and equipment instructions to choose the right type.
What current rating of RCD do I need?: Choose an RCD whose rated current is at least the maximum load of the circuits it protects and is coordinated with the upstream fuse or breaker. Typical choices are 63A, 80A or 100A for a split load board. Because an RCD gives no overload protection, the circuits behind it still need correctly rated MCBs.
Should I fit a 2 pole or a 4 pole RCD?: Fit a 2 pole RCD on a single-phase supply and a 4 pole RCD on a three phase and neutral supply. The 4 pole version monitors all three lines and the neutral together, so it can detect leakage on any phase. Make sure the device matches the board's busbar arrangement and module space.