Test your RCDs — HomeGraft

Test every RCD in your consumer unit to confirm it cuts power instantly, keeping your home protected from shocks.

RCD-01Prepare and warn the householdTell anyone in the house that the power may cut out briefly. Check nothing sensitive is mid-task, such as a computer saving a file or a recording in progress. Note the time so you know if any clocks or timers will need resetting afterwards. Grab a torch if your consumer unit is in a dark cupboard or under the stairs.

1 each · Torch

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RCD-02Find your consumer unit and identify each RCDYour consumer unit is usually under the stairs, in a hallway, utility room or garage. Look for switches marked with a 'T' or 'Test' button — these are your RCDs or RCBOs. Modern boards often have one RCBO per circuit, so a fault only cuts one thing off. Older boards may have just one or two RCDs, each covering half the house, so test every one you find.

RCD-03Press the test button on the first RCDPress the T button firmly with your fingertip. You should feel and hear a sharp click as the switch flips to OFF, cutting power to that circuit or circuits. This is the RCD doing its job correctly. Note down which lights or sockets went off so you know what that RCD covers.

1 each · Notepad and pencil

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RCD-04Restore power and repeat for each RCDFlip the switch back up to ON. Confirm the affected lights or sockets come back on. Move to the next RCD or RCBO and repeat the test one at a time, never more than one switched off at once, until you've tested every RCD on the board.

RCD-05Deal with any RCD that fails to tripIf pressing the test button does nothing, that RCD is not protecting the circuits behind it. Stop using that RCD as your safety net and get it checked as soon as possible. Do not open the consumer unit or attempt any repair yourself.

RULES

KNOW THE RULES

A faulty RCD, or any repair or replacement of parts in the consumer unit, is notifiable electrical work under Part P of the Building Regulations. It must be carried out by a registered electrician.

RCD-06Reset clocks and log the testReset any clocks, timers or smart devices that lost power during testing. Write the test date somewhere you'll see it, such as a sticker inside the consumer unit door. Test all RCDs again in three to six months — most manufacturers recommend this as routine good practice.

1 pack · Small sticker labels

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