Strange Fault

[Spark123]

Assuming it is a TT system it is dangerous, as others have said - all circuits need to be RCD protected in a TT system (it is very very difficult to achieve a low enough EFLI for an MCB to disconnect in time hence the reliance on RCDs).
How old is the CU, when was it installed and who installed it? Were they qualified? Do you have the relevent paperwork to go with it?
As RF says, a picture of the CU with the cover off will help too.

 

[1550]

Quite easily. Wait and see what the pics reveal though , could easy just be a mistake too ,easy done.

 

[securespark]

WHY ARE WE WAITING?

WHY ARE WE WAITING?

WHY ARE WE WAITING?

OH, WHY ARE WE WAITING?

(Sung at moderate tempo..)

 

[Taylortwocities]

We are waiting because the problem is at another premises. Won't get a pic until tomorrow at a guess. We'll then probably see that he forgot to remove the link between the two neutral busbars....

 

[Spark123]

And probably installed a dangerously wrong consumer unit for a TT system.

 

[ban-all-sheds]

We'll then probably see that he forgot to remove the link between the two neutral busbars....

How could that be?

I am part one qualified and have worked in the electrical trade for over 6 years so I know what not to do etc.

 

[Spark123]

I know people who have worked in the electrical trade for 12+ years, our local wholesalers has had the same trade counter assistant for ever!

 

[Stoday]

I've worked in the electricity industry for 45 years but BAS still tells me I'm a ****...

 

[bernardgreen]

I know people who have worked in the electrical trade for 12 weaks ( or weeks ) and are considered Best Qualified Experts, B Q Experts

 

[steviez]

Sorry guys but I have not had chance to go back yet as im very busy at work. I can tell you all though that the CU is about 5 years old and is just a standard split load board with RCD one end and main switch the other end.

 

[Spark123]

If it is, as you imply, a TT system then it is dangerous.

 

[steviez]

well the board is been replaced anyway so it will be dual RCD when rewired. Im going back to measure for voltage across earth and neutral tomorrow to make sure its not an external fault.

 

[Spark123]

Probably not an external fault, could be a fault on a circuit on a non-RCD protected way that cannot disconnect.
Could be a problem with the electrode.