Cu change fault

[Electroglow]

To today moved a cu and ring triped quick test and 230v on live earth and N...

Split ring and the other leg had 230v on earth... All volts came up when the live was in mcb and on..

Any one got idea befor I go back tomoro and sort it?

 

[batty]

Well it must be something you have done you say you have moved a CU. I take it you have extended cables?

 

[ProDave]

To today moved a cu and ring triped quick test and 230v on live earth and N...Split ring and the other leg had 230v on earth... All volts came up when the live was in mcb and on..

Any one got idea befor I go back tomoro and sort it?

I haven't got a clue what you are talking about?

"230V on earth" measured with what from where?

"All volts came up when the live was in mcb and on" Well that's what you expect isn't it? you are hardly likely to get any voltage if live is not in the MCB or the mcb is not turned on?

What tests have you done? Basic ring continuity on L, N and E? insulation resistance?

What alterations have you done to the circuit?

Was it a new CU or just the old one moved?

 

[PC Electrics]

I can't make head nor tail of the fault description either.

 

[batty]

Well if you have 230 volts on all cores you must have nailed or shorted the cable some how.

 

[Theorysparky]

keep splitting the ring,,,,,the fault may have been there before you started.....

what are your IR readings ???

 

[ProDave]

Well if you have 230 volts on all cores you must have nailed or shorted the cable some how.

Or you have forgotten to connect neutral and earth in the CU so they are just floating, and there's still a house full of stuff plugged in.

 

[batty]

Very true Dave a lot more info is needed to what has actually been done. This sounds a bit like one of the fault finding threads.

 

[ProDave]

Very true Dave a lot more info is needed to what has actually been done. This sounds a bit like one of the fault finding threads.

Only there, the person posing the question knew the answer.

 

[OnOff]

Wouldn't the "basic" dead tests on the ring have shown up an issue beforehand? Anything happen afterwards? Clocks nailed to the wall etc? Faulty (cheap?) breaker?

BTW, Brian Scadden's book on testing & inspection is very good................

 

[springcrocus]

Why would anyone change a CU without doing a few basic tests beforehand? Would you change a punctured tyre without checking that the spare was actually inflated? ?:|

 

[SPECIAL LOCATION]

To today moved a cu and ring triped quick test and 230v on live earth and N...Split ring and the other leg had 230v on earth... All volts came up when the live was in mcb and on..

Any one got idea befor I go back tomoro and sort it?

Sorry but if I replied honestly to this I think Admin would ban me for a few weeks!

:_|

Shall I just say No COMPETENT person would ever re-energise anything without having first done the standard basic tests to verify the integrity of the circuits before putting power onto them..

thus the situation you describe can only happen due to incompetence..

headbang

Yes I have got loads of ideas...

 

[springcrocus]

Sorry but if I replied honestly to this I think Admin would ban me for a few weeks!

:_|

Shall I just say No COMPETENT person would ever re-energise anything without having first done the standard basic tests to verify the integrity of the circuits before putting power onto them..

thus the situation you describe can only happen due to incompetence..

headbang

Yes I have got loads of ideas...

Seems to be happening a lot lately.... :|

 

[Bacon]

I allways carry out some basic tests prior to a CU change and explain to the customer as to why i'm doing them as,

Because it works now but may not show a fault,

But with a new CU and MCB's it may identify a fault thats not apparent until changed,

Like the borrowed neut on lights.

Plus it doesn't make you look like a numpty when some think doesn't work after you've done the change.

Now i'm off to Mexico for 2 weeks hols.

 

[OnOff]

I allways carry out some basic tests prior to a CU change and explain to the customer as to why i'm doing them as,Because it works now but may not show a fault,

But with a new CU and MCB's it may identify a fault thats not apparent until changed,

Like the borrowed neut on lights.

Plus it doesn't make you look like a numpty when some think doesn't work after you've done the change

Now i'm off to Mexico for 2 weeks hols.

Wise words there. Many scenarios there I guess e.g an existing breaker could be seized or an RCD maybe not functioning. Or cable damage, no existing earth fault detection/protection and you put in an RCD - whole new set of problems and as far as the customer is concerned the NEW cu that YOU fitted isn't working!

Case in point I had that many years ago when I very little electrical training and didn't even know what testing was. Helping the father in law re-wire and he said "Leave the kitchen alone that's only just been done!". So I did. Fitted a new cu with just the one RCD up front - replacing an old fused board. After it was finished they were watching TV one night and the adverts came on during Brookside (says how long ago). Out to the kitchen to make tea and using the kettle the whole house plunged into darkness. I get called (blamed?). Turns out loose faceplate on the socket for the kettle, no grommets in the back box hence it had chaffed thru the 2.5 T&E! After the event always takes longer!

(Mexico........can I come with you........wife and kids still in bed so could sneak out NOW!

 

[steptoe]

Mexico........can I come with you

and 1 more amigo,

gotta be better than the hurricane its blowing here just now!