electrical testing of circuits

[5544]

Hi,
i had a customer phone me to say that he had a fitter from one of the retailers come to his house today to supply and fit a new oven. said the man plugged in a tester to the cooker socket and said that the circuit had failed giving a value of 20 to 30 'somethings'?
the man went upstairs and did the same again, and he came down saying the whole house was at fault.

i am trying to work out what he tested at the sockets.

1. Zs doubt it (would they do that)
2. Milli amp leakage (doubt it, no appliances were unplugged)
3. RCD tripping nothing was reset?

the house apparently has a 17th edition board with split RCD's

can someone enlighten me what it is they test.

many thanks

 

[Richard Burns]

Depending on the tester used they may be measuring different things, however the likelihood is that they were using a plug in tester to measure the Zs of the circuit.
Having a value of 20 -30 however seems very high for a Zs reading unless it were a TT system, which it could well be and would then be OK.

 

[Richard Burns]

I should say that the fitters are not normally very accurate in their assessments and are just looking for a green light, if it is red then they do not fit.
You would need to see the installation to assess properly and see if there is a problem or not.
If it is a TNCS or TNS system and the EFLI is 20-30 then there could be an earthing problem, but you will never know unless you go there and test properly.

 

[Pete999]

If he used a plug in tester like the one shown earlier, it wouldn't give an accurate reading, if as you say you have a 17th edition CU then presumably you have a certificate, at least you should have.

 

[telectrix]

Hi,
i had a customer phone me to say that he had a fitter from one of the retailers come to his house today to supply and fit a new oven. said the man plugged in a tester to the cooker socket and said that the circuit had failed giving a value of 20 to 30 'somethings'?
the man went upstairs and did the same again, and he came down saying the whole house was at fault.

i am trying to work out what he tested at the sockets.

1. Zs doubt it (would they do that)
2. Milli amp leakage (doubt it, no appliances were unplugged)
3. RCD tripping nothing was reset?

the house apparently has a 17th edition board with split RCD's

can someone enlighten me what it is they test.

many thanks

get your arse round there. check the means of earthing. measure Ze and Zs. depending on the results, you can then advise your customer correctly. high Ze? phone DNO. Ze OK but Zs high? advise client that some investigation is required at an hourly rate. sorted. simples.

 

[Geordie Spark]

Hi,
i had a customer phone me to say that he had a fitter from one of the retailers come to his house today to supply and fit a new oven. said the man plugged in a tester to the cooker socket and said that the circuit had failed giving a value of 20 to 30 'somethings'?
the man went upstairs and did the same again, and he came down saying the whole house was at fault.

i am trying to work out what he tested at the sockets.

1. Zs doubt it (would they do that)
2. Milli amp leakage (doubt it, no appliances were unplugged)
3. RCD tripping nothing was reset?

the house apparently has a 17th edition board with split RCD's

can someone enlighten me what it is they test.

many thanks

You may as well have asked "How long is a piece of string"

Go there and look at it THEN ask your questions - if you need to.

 

[Guest77]

You may as well have asked "How long is a piece of string"

Go there and look at it THEN ask your questions - if you need to.

I have said before, it is half the length when folded in half and twice the length when unfolded again

 

[Geordie Spark]

I have said before, it is half the length when folded in half and twice the length when unfolded again

Good lad!

I knew I could always rely on you to provide the right answer.