New Consumer Unit - keeps tripping

[kevinmcd396]

Hi

Wonder if anyone can help before I bite the bullet and buy a new oven and other appliances? I wanted an old fuse board replaced by a new consumer unit for overall safety reasons and in that I wanted to extend services out to the garage. Got an MK 10 way fitted by a well recommended local electrician a month ago - all looks to be a sound job.

Problem is it keeps tripping:

- grill trips it immediately
- the kettle trips it when the oven is on
- the oven now trips after 10 mins irrespective of the kettle
- the immersion heater trips it straight out
- toaster and oil filled heater work fine - same with all other appliances.

I appreciate that the new unit RCD will be sensitive and pick up appliances and elements that are on their way out but we never had any trips beforehand and before I go out and buy a new oven, kettle, toaster and immersion heater (which will cost me an absolute fortune) it would be good to find out if the RCD component is faulty. By way of a test I have a 1.8Kw oil filled heater which I plugged it but that didn't trip it?!?

I've contacted my electrician and am awaiting a reply. Any advice now would be great as I'm inclined to buy a new oven now for ready to fit at the weekend.

Thanks for any help in advance.

 

[EFLImpudence]

It will be just as well to wait until it has been inspected.
There's not really any point speculating.

A new element may be all that is needed for the oven or it could be something else.

 

[Jackrae]

Your electrician will have the necessary test equipment to test the RCD trip current and trip time.

He will also have the necessary test equipment to verify circuit insulation and fault impedances.

If he doesn't, then he shouldn't have fitted your consumer unit as he couldn't issue the relevant post fitting test reports.

Unless ...............

 

[kevinmcd396]

Your electrician will have the necessary test equipment to test the RCD trip current and trip time.

He will also have the necessary test equipment to verify circuit insulation and fault impedances.

If he doesn't, then he shouldn't have fitted your consumer unit as he couldn't issue the relevant post fitting test reports.

Unless ...............

Thanks both - I'll give it a day or so and wait for him to come back to me and live on gas boiled grub in the meantime. He owes me the part P certificate anyway and don't think they are the kind of firm to have done a bad job and/or not provide it. They did my next door neighbour's fuse board and come highly rated on Checkatrade too. I was at work when it was fitted but my wife tells me after it was fitted he 'fiddled with lots of things' including the cooker. So hopefully the right post installation checks were performed.

 

[sparkwright]

In the meantime, why not send a photograph of the new consumer unit, just out of interest.

 

[xr4x4]

So it's the rcd that trips every time? And I'm assuming there's two in the cu?

 

[HERTS P&D]

In the meantime, why not send a photograph of the new consumer unit, just out of interest.

Santa?
Nick Clegg?
Katie Price?

Go on Sparky, who will he send the picture too?

Andy

 

[kevinmcd396]

So it's the rcd that trips every time? And I'm assuming there's two in the cu?

Hi yes - just the RCD on the left hand side - there are 2 in the unit. Photo hopefully below. The electrician had replied back saying that it doesn't sound right and he will come back next week swap out the RCD and re-test. So that's good. No oven impacts upon my wife's whinge nerve and she had got her hopes up on a new oven but since were broke she'll hopefully have to make do with a new RCD!

 

[xr4x4]

Why do people put all the lights on the same rcd.

 

[PrenticeBoyofDerry]

Hi yes - just the RCD on the left hand side - there are 2 in the unit.

Try plugging some of the appliance into the second RCD, if you have socket circuits on it, if you need to use an extension lead do so.
Then see if they trip the second RCD

The electrician had replied back saying that it doesn't sound right and he will come back next week swap out the RCD and re-test.

Although trip times are important ask the electrician to do a ramp test on the problem RCD for you and also ask if they can do some investigation into the earth leak of your appliances.
PS MK CU quality is something to be desired!
If the unit is new the parts should still be under warranty if faulty!

 

[Aragorn84]

Why do people put all the lights on the same rcd.

Borrowed neutral + lazyness?

 

[PrenticeBoyofDerry]

Why do people put all the lights on the same rcd.

Should that be why do some people? Don't tar all us people with the same brush!

 

[pompeygit]

First of all he sounds a great electrician. Coming back next week with so many problems is p*ss poor service. Proper testing before and during installation would have highlighted any problems. It would be interesting if you could post a copy of the test results up.

 

[PrenticeBoyofDerry]

First of all he sounds a great electrician. Coming back next week with so many problems is p*ss poor service.
Proper testing before and during installation would have highlighted any problems.

Within the hardwiring of the system! It is very likely the issue is down to earth leakage of appliances an the CU/RCD are only doing what they are meant to do. So can hardly expect the electrician that has been asked to install a new CU, to go PAT testing all of the appliance. When I install residual current devices, I inform the customer/client of the RCD functional operation (and periodic test of button) and likely causes for tripping, highlighting that heating elements of appliance can give high leakage currents.

It would be interesting if you could post a copy of the test results up.

Always interesting to see them! But what is it going to really tell us, if the IR readings are within the permitted range?
Trip times will not offer any additional info into resolving the problem.
Need ramp test which are not produced on EIC certificates and earth leakage values of appliances also not remarked upon within the EIC.

If it's a faulty RCD then fair enough, but cannot really discredit the electrician for installation on trust a factory manufactured unit that should have been tested prior to being boxed up! I will discredit them however for purchasing MK CUs as they are pants!

 

[pompeygit]

Sorry PDB I'm getting cynical in my old age. But with so many problems of 'earth leakage' I just got a bit sceptical. My view of this is coloured by the fact that the OP has so many problems and the electrician is coming back next week. I'm sure you wouldn't be happy to leave a customer in such a bad situation.