Functional checks and RCD socketsDoes it work, and does it switch off?

After the electrical tests comes the obvious one that people forget: does it work, and does it switch off?

• Operate the appliance's own switch or dial — on and off
• Check the socket outlet it's plugged into works too
• A kettle gets filled with water before this — don't run an element dry

RCD-protected sockets and leads

Where an extension lead, socket-outlet or mobile distribution unit has its own RCD, it must be rated 30 mA or less (protecting socket-outlets of 32 A or less). Section 10.11 gives two checks:

• User check (formal inspection, or combined inspection and test): plug it in, switch it on, then with no load connected press the test button. It should operate and disconnect the supply.
• Performance test (combined inspection and test), as a minimum: 150 mA, and it should disconnect within 40 ms.

If the RCD is suspected of operating outside its specification, the other tests in Table 10.5 can be done as well:

10.11 · test button, then 150 mA within 40 ms · p.77 Table 10.5 · RCD trip times · p.78