New CU Fitted a few teething Issues to sort.

[KRIS537]

Had a new CU fitted at the weekend. But there where a few teething issues to sort out.

First one was the garage kept tripping the electrics out, so the electrican put it on a none RCD protected curcuit. This not an issue for me atm as im having that redone at some point as a workshop.

The main one was the Immersion hot water cylinder. First off the feed to this also powers the boiler but is only a 1.5mm cable. He says thats fine for a boiler but not an Immersion. so im going to have a 2.5mm cable fitted soon as a seperate feed. The issue I have is the MCB trips every so often, but the RCD doesnt. What could be causing this issue?

 

[hasel5]

Wind up ?

 

[Steve_P]

Wind up ?

Don't think so but the OP really should be cornering the spark that changed the CU with all the info on this thread. Definitely for the EIC and wanting to know when the certificate of compliance will be sent through and who from. . . . . . .

Why do I have that nagging feeling that there's no intention of this being notified?

 

[KRIS537]

Don't think so but the OP really should be cornering the spark that changed the CU with all the info on this thread. Definitely for the EIC and wanting to know when the certificate of compliance will be sent through and who from. . . . . . .

Why do I have that nagging feeling that there's no intention of this being notified?

tbh if I had not of started this thread I would not of known that I need the EIC, and looking online, there def was not one with the paperwork he handed me. So I will be chasing this up. All i was aware is that it has to be done by a qualiifed electrican.

 

[telectrix]

I'm not in disagreement with you, though my first thought on things like kettles welded is 'how well were they wired in the first place?'

think it was down to poor quality sockets. wiring was fine in both cases.

 

[PhilRance1950]

Well back to the issue of the Mcb Tripping and not the Rcd . if you think logically about this if the Mcb trips out you have a live to neutral fault .If the Rcd trips out you have a live to earth fault . Did your electrician test all circuits when he installed new board

 

[brman]

If the electrician is coming back to do more work (wire up the immersion heater etc) then it should not take him long to test the loads on that circuit and see why the MCB is tripping.

Don't panic too much about not getting a cert yet, quite a lot of sparks will post them on afterwards, often after a week or so when they catch up with their paperwork...
Often this is deliberate as it is nice to be sure the payment doesn't bounce before giving the paperwork
Does no harm to mention it to him so he knows you are expecting one though.....

 

[KRIS537]

Well back to the issue of the Mcb Tripping and not the Rcd . if you think logically about this if the Mcb trips out you have a live to neutral fault .If the Rcd trips out you have a live to earth fault . Did your electrician test all circuits when he installed new board

thanks for that think that confirms what was said that the element is breaking down. He did check the circuits, as he picked a few issues.

 

[ample current]

Well back to the issue of the Mcb Tripping and not the Rcd . if you think logically about this if the Mcb trips out you have a live to neutral fault .If the Rcd trips out you have a live to earth fault . Did your electrician test all circuits when he installed new board

Now i always thought an MCB tripped due to over current
and an RCD tripped when there was an imbalance of current between the live and neutral conductors, so if there was a leak to earth from the live, there would be a difference in the live and neutral current thefore it would trip when the difference reached 30mA or what ever it is rated to.

 

[Geoffsd]

if you think logically about this if the Mcb trips out you have a live to neutral fault

Or Live to CPC Earthed part.

If the Rcd trips out you have a live to earth fault .

Or Neutral to any Earth.

 

[Octopus]

tbh if I had not of started this thread I would not of known that I need the EIC, and looking online, there def was not one with the paperwork he handed me. So I will be chasing this up. All i was aware is that it has to be done by a qualiifed electrican.

So what has he given you then??

 

[yellowvanman]

Being pedantic here but

Live = line and neutral

I know we all use the term live for the brown but technically it should be line - see definitions in Green book

 

[snowhead]

well, having seen plugs welded into sockets on just 2kW kettles, either their calculations are wrong, or sockets compliant with BS1362 just ain't.

I've lost count of the number of melted plugs sockets with less than 3kw load on them that I've changed.
I've also lost count of the number of years I've been finding them.

It's more likely to occour with cheaper plug or socket combinations, but hasn't stopped it happening on Mk socket / Mk Plug, when Mk were the best.

Moulded on plugs aren't any more reliable.

 

[Geoffsd]

Being pedantic here but

Live = line and neutral

Accepted.

If you're that pedantic you're going to be busy on here. :smile5:

 

[ezzzekiel]

i would be concerned as to why he bypassed the garage rcd as it was tripping,

 

[whitestu]

Trust me this house is an electrical nightmare, what scares me the most the previous owner was an electrican. Dont worry hes not done any work to my house since i bought it lol. He has normal grey PVC cabling powering outside sockets, the garage etc etc. Im slowly getting stuff corrected and done right.

There's nothing inherently wrong with using T&E outside as long as it is installed properly, on a wall, in conduit for example.