RCD trips when plug appliance in (but switch is off)

[Robf100]

Hi there,

A question out of curiosity more than anything. Our washing machine has just given up and tripped the RCD. Turned switch off, removed plug, reset RCD. I then plugged the washing machine back in (wanted to see if it may have just overheated or something) and the RCD tripped immediately, even though the plug socket was switched off. As I say, just curious. Why is this? If the socket is off, then doesn't that mean there's no live current and so how could it trip just by plugging it into the (off) socket?

As you can tell, complete novice with electrics here and I'm sure this is a really obvious answer, but got me scratching my head!

Cheers,
Rob

 

[EFLImpudence]

Probably a fault between Neutral and Earth.

Heating element is the most likely problem but could be something else.

 

[Taylortwocities]

SOme of teh cheaper sockets only switch off the live side leaving the neutral connected. An RCD will trip if it sees an earth to neutral fault.

try this. Unplug WM. Does RCD trip?

If no then plug in the WM and switch it on. Does the RCD trip? If yes it looks like the WM is knackered.
Get an APPLIANCE REPAIR MAN (ie not an electrician) to fix it.

 

[PrenticeBoyofDerry]

The RCD will detect earth leakage between neutral and earth, so even though you have switched the socket outlet off, you have only disconnected the line/live conductor as your socket has a single pole switch, so neutral and earth of the washer are still connected.

 

[PrenticeBoyofDerry]

Likely fault is a heating element. They can be replaced.

 

[Robf100]

Thanks for the replies all, appreciated! Luckily we were about to get a separate washer / dryer anyway, but not understanding why the rcd would trip with the socket off was driving me crazy!