Electric Trip Switch

fwor

Interesting - I guess it's true that a small current would flow for a short duration, before the neutral line got pulled down to actual earth, but hadn't expected that such a short duration difference would trip the RCD.

Must admit when I've been doing paper steaming the sight of condensed water dribbling down behind the light switches always worries me... Hopefully it will all have dried out pretty soon for the OP though.

DVardysShadow

fwor wrote: »

Interesting - I guess it's true that a small current would flow for a short duration, before the neutral line got pulled down to actual earth, but hadn't expected that such a short duration difference would trip the RCD.

Bear in mind that the RCD is current operated. And to pull N down [or up] to E, a current must flow. So what matters is not the time taken to pull N to E, but the current which flows when they are pulled together.

societys_child

Or, is it possible that the switch has tripped to the center position . . . and needs to be switched "fully off" before it can be switched back on?

Just a thought

fwor

DVardysShadow wrote: »

So what matters is not the time taken to pull N to E

That's not strictly true - RCDs are time-sensitive, specifically to avoid false tripping.

But thinking about it further, I can see that other loads - outside of the property in question - could easily be the cause of the voltage difference on neutral, and that alone could result in a small current flowing all the time, rather than just for a short duration.

cabbage

We had something similar tripping every morning around 7am. We couldn't work out what it was as nothing was being turned on at that time. In the end we found a leak in the loft that was very very slowly dripping down the pipes, through the house into the garage and into the plug socket behind our tumble dryer. It took ages to find but now its fixed there are no mysterious power cuts.

baldelectrician

It sounds to me that some water has got in to the back of a socket

I would suggest you have somoene (who is compotent) remove and replace the socket(s) where the water has caused a problem

You should use a competent person for the work, links below
In Scotland:
Individuals registered;
http://www.sbsa.gov.uk/register/ListAC.asp
Companies
http://www.sbsa.gov.uk/register/SearchCo.asp?T=Construction&ID=2
In England and Wales:
http://www.competentperson.co.uk

DVardysShadow

fwor wrote: »

That's not strictly true - RCDs are time-sensitive, specifically to avoid false tripping.

It is quite true enough for addressing the issue I was addressing. RCD's may be time sensitive, but this is irrelevant. The time taken to pull N to E does not come into it, because the current will flow for all the time N is pulled to E if there is no RCD. It is the action of the RCD which stops N being pulled to E

fwor wrote: »

... But thinking about it further, I can see that other loads - outside of the property in question - could easily be the cause of the voltage difference on neutral, and that alone could result in a small current flowing all the time, rather than just for a short duration.

This is exactly what happens and the currents could be substantial