Does your RCD work properly?

Most homes now have at least one RCD (Residual Current Device), if not two if wired to BS7671:2001 (16th Edition Wiring) or to current regulations BS7671:2008 (17th Edition Wiring), where ideally they should be rated at 30mA trip.

Each RCD is equipped with a “Test Button” – and instructions are usually left on or near your Consumer Unit (Fuse Box) to test quarterly – this is worthwhile as it is a good functional test to ensure it mechanically operates.

In accordance to BS7671:2008 Appendix 3A, A 30mA RCD should safely disconnect the supply with the following time/current performance criteria:

@ Half current (15mA) = NO TRIP
@ Full current (30mA) = 300 milliseconds MAX
@ TWICE normal current (60mA) = 150 milliseconds MAX
@ FIVE times normal current (150mA) = 40 milliseconds MAX

Of course to generate a test current of five times the normal current and time it with a stop-watch is virtually impossible for the home-owner. This is why we always carry specialist calibrated RCD testing equipment to ensure each RCD we test functions correctly.

RCD Testing is a service we provide – if you would like your RCD(s) professionally tested please contact us to arrange an appointment – our electrical inspection tests start from as little as £35.

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