rcbo tripping

[sajeel]

Rcbo keeps tripping when earth connected it is non earth rcbo. Have performed continuity test on wiring no fault on wiring any ideas ?
Circuit is 10a for exterior lighting although nothing connected yet want to sort out earth fault first. Supply is 3 phase tn-c

 

[eganelectrical]

Is it on a neutral bar with another rcd but on a different busbar to the same rcd?
Is it only tripping when you pull a load??

 

[sajeel]

It is inside commercial db no rcd just mcb and rcbo mix 32 way db only one neutral and earth on each side. It trips even with no load when earth is connected no short found on continuity tests

 

[telectrix]

you need to do IR tests, not continuity. my guess is a N-E fault. if it's outside equipment suspect water ingress.

 

[Brightspark2]

Have you not got another RCBO to try?...

Could be faulty....

Are you saying it trips as soon as you put the CPC into the earth bar?...but all IR tests good?...

 

[eganelectrical]

Could also be live to earth fault!! Usually neutral to earth trips when pulling a load. Turn all other circuits off when trying to make sure.
Yes I.r test is required.
Test the rcd trip with an rcd tester!! X 0.5 shouldn't trip it.

 

[Engineer54]

Could also be live to earth fault!! Usually neutral to earth trips when pulling a load. Turn all other circuits off when trying to make sure.
Yes I.r test is required.
Test the rcd trip with an rcd tester!! X 0.5 shouldn't trip it.

A neutral to earth fault/connection, will trip a connected RCD device, with or without an applied load!!

 

[eganelectrical]

Fair enough? I'm sure I had one tripping in the past when the load was pulled. Will this trip even though there are no other circuits connected? (Not saying your wrong)