rcbo tripping times

[sparkygrant]

Hi all help please,I tested a6 amp rcbo30ma at board with out load connected the rcd results are 310ms at times 1 and 50ms at times5 so I changed it thinking it was faulty tested new 1I fitted got same results I then rcd tested another rcbo in the board another lighting circuit results are fine I then tuck the 1I tuck out because I thought it was faulty and put in my board at home and the results was fine has any one come across this before and can someone please help with this situation cheers

 

[Richard Burns]

If there is some electrical equipment present that has a capacatative value that is connected across neutral to earth as may the case in some electronics, particularly on lighting then this can absorb some of the current generated by the tester and delay the switching of the RCBO.
Then again a very long length of cable can also have this effect but not normally at these levels.
You could try disconnecting the outgoing neutral or earth and seeing if that has an effect.
Try and get the RCBO as isolated as possible from all other influences.

 

[sparkygrant]

I will mate I have tried taking the out going live and neutral out and get the same results just never come across this before so any help much appreciated