Low ir reading

[Proper Job]

Isn't it ok to join the live and neutral together and test down to earth? I did this today on 250 volts as there are dimmers on the circuit and lv lights and a smoke detector. Having done this I got readings of somewhere around 1.6 m ohms. I left that circuit as it is not urgent to finish it yet so I thought I would ask the question to see if you guys can help.
Advanced apology for sounding stupid ;(

 

[Marvo]

Yes you can but if you IR test with items still in circuit the any surge arrestors etc may give you false readings.

 

[Plonker 3]

Yes, if its a EICR. Although the test voltage has to be twice that of the circuit being tested,

 

[spark 68]

Yes, if its a EICR. Although the test voltage has to be twice that of the circuit being tested,

Not quite true Dilb, circuits up to 500V are tested at 500V(excluding SELV and PELV), BS7671 allows the test to be carried out at 250V where it is unreasonable to disconnect sensitive equipment subject to a minimum of 1 Megohm.

In this case though I would link out and bypass the dimmers and re-run the test on that circuit at 500V, as IMO it warrants further investigation.

 

[Plonker 3]

Cheers, had that value in my head for some reason.

 

[guest119]

Should be much higher with l and n tested to earth, agree with you.

Boydy