Socket trips RCD when switching on, but not when it's already on!

[Fordy81]

So we have a low mounted double socket (with switches) in our kitchen for appliances, which runs via a worktop height fused spur. We only have the tumble dryer plugged in to this.

I've just discovered that if I turn the switch off of the left socket, then turn it back on, it trips the RCD, regardless of whether the TD is on or off. The right side doesn't seem to do this. However if the TD is plugged and the switch is on, like now, after I'd reset the RCD it's fine.

I should add the main RCD went off, not an individual one!

Is this just a faulty switch or something more sinister?

Was thinking of just changing it over to a switchless socket!

Thanks

 

[sparkwright]

Don't fully grasp it all but get the gist.

Sounds like a faulty socket.

Some sockets have single pole switches, some have double pole switches.

Single pole cuts the live. Double pole cuts the live and neutral.

Perhaps you have double pole switches, and the switch is not cutting both live and neutral at the same time.

Most sockets have it printed on the back if double pole or single pole.

Would be a good idea to check it is wired correctly, though there is nothing to suggest that it isn't.

A plug-in socket tester would help to see what is going on with the socket, but it does sound like a faulty socket.

 

[Taylortwocities]

I assume it still trips with nothing plugged in?