flat down neutral to earth reading

[aidley]

Hi I have a flat down neutral to earth fault on a kitchen ring rcd isnt tripping and I have 30+megohms on the other ir tests! There is.extractor fan in the kitchen that has no fcu

 

[Pete999]

What is the reading for the IR test N-E? are your tests carried out with the RFC conductors sill connected to the CU?

 

[Octopus]

Did you do the Ir test with the neutral disconnected?

 

[aidley]

All cables of the ring were out of the board when tested and the neural to earth reading was 0 ohms

 

[Pete999]

All cables of the ring were out of the board when tested and the neural to earth reading was 0 ohms

Meg ohms you mean

 

[aidley]

Yes mate hangover brain

 

[Octopus]

Still not totally with you. What was the Ir l-n?

 

[aidley]

30 megohms and similar l to e

 

[Plonker 3]

What results did you get when you cartied out both a ramp and time test on the RCD?

 

[aidley]

18ms on 5x and 37ms on 1x
Not got a ramp test facility on the tester

 

[Plonker 3]

Well you need one as you have to prove the RCD is operating at the correct fault current.

 

[aidley]

Would an extractor fan bring the readings between n-e down just thinking they may have spurred it off and im reading through that

 

[Plonker 3]

Did you test the induvidual leg too the fan? Did you look insude the fan?

 

[aidley]

I have isolated the leg thats down split the ring and put it on 2 20amp breakers so I can leave it safe till Monday!The leg thats down seems to run close to tge extractor looked inside and there is 1 x1.5 but no sign of a fcu so assumed it was part of the lighting circuit! If it has been spurred off the ring could this give me the strange readings

 

[Plonker 3]

So you have identified the faulty leg, how do you plan on testing the RCD as that also needs to be replaced of there is a fault with it.

 

[aidley]

Yes was just wondering if a spurred off extractor could effect my readings before I have to put new legs in

 

[Octopus]

30 megohms and similar l to e

So fixed fan, no isolator and relatively decent results??? This doesn't add up

 

[aidley]

Yes except neutral to earth which is zero

 

[Octopus]

Yes except neutral to earth which is zero

I think you need to disconnect the fan and redo the test.

 

[aidley]

So that could bring the n-e down? Hopefully it is that dont really fancy putting a fresh leg in