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Mend Consumer Unit Trips

Why does my RCD trip?

I've got a new consumer unit with split load. The RCD switch trips frequently but sometimes will go a week before tripping.
There is a ring main and lights on it. The only things on when it trips are freezer,cooker clock and security lights.If there was a fault on any of these wouldn't it trip continually? What can I do to test and fix it?

Ken
March 2007
What a load of bollocks?
You can measure Earth Leakage, you can measure sensitivity!
Don't try and replace an RCD, get a real sparky to test it!

A real Sparky
May 2014
The ONLY way to tell is by plugging one thing in at a time and waiting to see if that is the cause of the trip. RCD'S SUCK. Sometimes there is just no f***ing way to figure out why the damn thing is tripping. Remove it and just put in a regular breaker, and check if your appliances are properly grounded. If an electrician comes and says he can tell you why it is tripping, he is lying. They trip with as low as 30 ma of leakage current, and he can't test to see something that small unless he has very sensitive, expensive equipment. I have yet to see an electrician with a meter that can detect 30ma in the time it takes to trip an RCD, and I've been an electrician 35 years.

Joe T
October 2012
Don't listen to NWC March 2008 he doesn't know what he is talking about ! The B, C, and D markings he is talking about don't relate to RCD's but MCB's. They are different protective devices. You need to call in a qualified electrician who is registered on a competent persons scheme with NICEIC or Napit. Look at their websites for somebody in your area. The rcd is tripping for a reason and a good electrician should be able to locate the problem for you. DO NOT ATTEMPT TO DO IT YOURSELF.

Competent Sparks
May 2010
you say theres a ring main with lights on?firstly are they external lights

sck
December 2009
I have just put in a new ring main the ring main is on a 32 amp mcb. I have also had an electricain put in a new db. now every time i put an appliance in the sockets the rcd trips why does this happen please can any one help

kevin d
December 2008
Split load consumer units must be correctly connected(the neutral bar is split also). What I mean is that the neutral connections and the line connections must be coordinated otherwise you could have nuiscance tripping. I ll give you an example, I went to a house one time were a bell transformer was fitted by a DIY person. When connecting he had connected the neutral into the 30mA trip side of the consumer unit and the line into the other half of the consumer unit. Either the transformer or the light on the bell push caused the RCD to operate continuously. Although I would reckon your last contributer is correct in his assumption about the motor in the freezer, and this should be moved to the unprotected side of the consumer unit.

Regards
Michael

michael
April 2008
Do not change your type B mcb;'s
These are the correct type for a domestic installation (resistive load) other types (C&D) are for inductive and capacitive loads normal found in the industrial or commercial sector.
It could be the motor/compressor in your freezer. Isolate it or put iit on a non rcd protected circuit then see what happens.
Failing that - call in a sparky - give some nice sparky in your part of the world a nice job. Make him tea, give him a bacon butty and don't baulk at his bill!

NWC
March 2008
RCD`s come as type B,C, or D.
B is the most sensitive, D the least sensitive.
B is also the safest.
If you have a B, change it for a C.
Or move cooker to unprotected side of C.U.(Sparky has the answers)

insulated gloves
March 2008
If your cooker is on the rcd side of your consumer unit,move it to the non rcd side.Cookers are not normally put on the rcd side because they tend to have earth leakage normally(as do immersion heaters).
Older Fridges also tend to have worsening earth leakage as there motors age.

SPARKY
April 2007
Have a look at your security lights.... you may be getting rainwater/dampness inside !

Pete
March 2007
it may be to sensertive. sometimesbig appliances can trip them. try changing it

vr electrics
March 2007
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