ALi-B

iTrader: (1)

Got a bit of a problem. My old mans Neff Washer/Dryer is connected to mains via a sepreate switched spur, which is also proected by an RCD that protects the whole ring main in the house.

Background info:
Being a modernish house (well, 15years old), with modern electrics, I believe the feed for the washer/dryer and dishwasher is on a sperate MCB but am yet to check. But either way, it still goes through the 30mA RCD unit.

Now for some reason the washer/Dryer is tripping the RCD intermittently. It only does it when it switches on to dryer mode. Reset the RCD and off it goes, it may trip once more within 10-20seconds of the machine restarting, but usually it'll carry on and run the full cycle. So I suspect there is no real fault with the washing machine apart from maybe a bit of arching in the switches/relays for (mechanical) controller, as if it was a water/heater element/earth shorting problem it would be tripping all the time, not when it just switches on.

I've had the machine out and on it's side with the top and rear covers off to check for leaks or obvious electrical faults to no avail - it looks like new inside! I've also observed it running with the covers off to check for any leaks that maybe causing it to trip. Again, not a drop. And the machine works fine.

Now, I might belive the RCD is a touch over-sensitive, as the iron also trips it. And it has done so with every iron used (3 intotal) I suspected it was from it being overfilled or spilling water, so never thought anything of it as you'd expect it to trip if you spilled some water on it!


Right that's background out the way with:

Questions:

Can RCDs go on the fritz and become ultra sensitive? It's a 30mA DIN rail type mounted in the main consumer unit.

Should RCDs be used to proctect large current individually spurred devices - especially white goods (i.e washers, dryers, dishwashers etc)?
Even when it is on its own MCB?
And would it be ok to re-wire the spurs so they are no longer protected by an RCD?
Or would I be breaking some sort of IEE wiring regulation now (apart BS of signing the work off by a qualified sparky)?


I remember many years ago people having problems with new houses which had sepreate RCDs fitted in the garage sockets (intended for power tools, mowers etc). Many people have freezers in their garage and they found that the RCD would trip every time their freezer kicked in, due to nature of how the compressor starts and having inferior supression. I suspect this might be the case with the washer dryer - it is an old school mechanical controller, and it is 20 years old - but it has seen such little use and is in such immaculate condition both inside and out, and it works perfectly fine, just it keeps flipping the RCD...and I'm getting rather annoyed at having to reset the clock on the video!

Answers to the question would be appreciated.

TIA
AL

andy97

iTrader: (1)

You need to check your appliances with an earth leakage test and insulation test

scud8

iTrader: (1)

Reminds me of a problem I had a couple of years ago when I changed my consumer unit to one with RCD protection on half the circuits. As soon as I switched on one of the socket circuits it tripped the RCD. I checked the live to ground resistance on that circuit and it was only 100 or so ohms.

After much trial and error I finally tracked it down to a fridge I had inherited from the previous owner. He was obviously not much of a handy-man as he had wired the plug with earth to neutral and neutral to earth.

Leslie

It is true that RCD's can become oversensitive. The more they get tripped the worse it can get too.

Les