TNCS

[Poncho1231]

Hi
Ive just installed a new 10 way split board in my house, the system is TNCS, upon checking a few sockets with my socket and see its coming up with single green light (earth missing)??? all the earths are correct on the CU and back to the 100amp fuse cartridge, would the earth and neutral be connected behind the head of the supilers 100a fuse housing? this is the only possible answer to the problem, can i eliminate this in my CU?

 

[Lectrician]

You need to test with a loop tester, as any spark would have done to record on his EIC.

You need to beg, borrow or pay a spark.

When you say 5+5 split - is that only half protected by a 30mA RCD? Have a google of "17th edition dual split".

 

[Poncho1231]

CU is a split board protected by 2 RCDs so 1 rcd per 5 mcbs

 

[ban-all-sheds]

Hi
Ive just installed a new 10 way split board in my house, the system is TNCS,

What was the Ze reading when you tested it?

upon checking a few sockets with my socket and see its coming up with single green light (earth missing)???

What were your R1+R2 and fault loop measurements for the circuit?

all the earths are correct on the CU and back to the 100amp fuse cartridge, would the earth and neutral be connected behind the head of the supilers 100a fuse housing?

Well you said it was TN-C-S, so what do you think?

this is the only possible answer to the problem, can i eliminate this in my CU?

You said that all the connections in your CU were correct, so I'm not sure why you think that changing them (which would presumably make them incorrect) would resolve the problem.

 

[ban-all-sheds]

PLAN B:

Get an electrician to sort out the mess which you have made because you were a stupid incompetent idiot who decided he could change a CU even though he knew SFA about how to do it properly.

 

[Poncho1231]

Ok i will test R1 and R2 and carry out an earth loop impedance test max value 0.35?

 

[ban-all-sheds]

Get an electrician you dozy t**t.

 

[Poncho1231]

All i asked was where the earth and neutral is connected? the board is correctly installed and set up as per 17th edition.

 

[EFLImpudence]

Apart from the above, is that what a single green light signifies?

 

[ban-all-sheds]

the board is correctly installed and set up as per 17th edition.

No it isn't.

... upon checking a few sockets with my socket and see ...

Ok i will test R1 and R2 and carry out an earth loop impedance test max value 0.35?

 

[Poncho1231]

yep on the fluke socket tester its "earth missing"!!!??? of course all the connecting within the sockets are connected and the same within the consumer unit, 10mm back to the gas and water and 16mm from consumer to the small 2 way copper block on the suppliers 100amp fuse block (henley)

 

[ban-all-sheds]

Click.

 

[EFLImpudence]

You said 'Socket and See' - never mind.

 

[ericmark]

This months wiring matters covers earthing and explains how and where connections are made.

The socket&see testers are good for a quick test but they don't give a reading and you need to quote the reading when filling in the installation certificate before submitting it to LABC for them to issue the completion certificate.

Before starting on a board replacement I would complete an electricial intallation condition report as any faults found after can cause problems in getting payment to correct. I would have the readings before and after fitting the board and should the earth be missing I would not start the job until either the DNO had provided the earth or the client had agreed to installing an earth electrode for a TT system. Electricians have a problem with two conflicting rules.
1) We must not make a house uninhabitable without ensuring alternative accomadation is available.
2) We can't energise power where it is not safe.
Therefore we need to be very careful that we can complete in the day or we may end up with hotel bills to pay.

I would have hoped you also used your scoket&see before you started and the question must be was it showing all correct lights before you started the job?

If I had made a mistake and forgot to test and then found no earth I would have to make into a TT until sorted or of course not power it up. We of course would not switch on any MCB's or RCBO's until the board passed not sure how you can do that with a plug in tester as all sockets will be dead until supply to board is tested?

 

[EFLImpudence]

Ive just installed a new 10 way split board in my house,

single green light (earth missing)???

all the earths are correct on the CU and back to the 100amp fuse cartridge The fault must be elsewhere then

would the earth and neutral be connected behind the head of the supilers 100a fuse housing? You said it was TNC-S and all earths were correct

this is the only possible answer to the problem, What is?

can i eliminate this in my CU? Eliminate what?