live to earth fault

[bredon86]

following a live zs test on a socket circuit. when i pres the test button it trips the rcd and not the breaker. there is continuity and ir for all all conductors on the circuit. Is this possibly and live to earth fault please help

 

[Jonesy83]

have you got your testers set on no trip?

if there was a fualt the rcd should trip without the test

 

[bredon86]

yeh i have a kt64 with anti trip.. any other suggestions?

 

[Spudnik]

Some RCD/MCB are known to trip, even on "no trip" settings

 

[Sparkypaul11]

Ensure your tester is set right, i.e... No trip on megger or D-Lock on others.

Whats your IR readings??

 

[bredon86]

dont knw it was downstairs and i was upstairs.. dnt think so. could it be a sensitive rcd

 

[bredon86]

tester is set fine. cuz all zs readings were fine happened on just one circuit...

 

[nickblake]

this may sound daft but youve got your test leads in the correct holes and not reversed the neutral and earth

 

[Sparkypaul11]

1) Check other ciruits on the same RCD to illiminate or prove correct the over sensitive RCD idea.

2) Is it at every point on that circuit or just one socket outlet?? ring or radial??

3) Have you conducted an R1+R2 and checked for neutral continuity and polarity??

 

[bredon86]

yes tester leads are in correct holes

 

[bredon86]

i only had one point accesible and it was just on one circuit on that side of the rcd. i did a continuity tests and they were fine.

 

[Graeme Harrold]

Ramp test the RCD and see what it trips at.........

 

[bredon86]

it wouldnt trip when i did a ramp test

 

[SEC-Tom]

it wouldnt trip when i did a ramp test

Do you have another RCD spare, id definitely check that out and if it's still tripping and not tripping on ramp then id have your meter checked...

 

[empress]

daft question is it a dual rcd 17th dis board? if so is your neutral conductor for dodgy circut in the right neutral bar.