Earth loop testing

[white1i]

Anyone got any ideas why my Robin KMP 4120 tester trips a 30mA/32A RCBO

I have tested the RCBO wirth an RCD tester and this check out fine

 

[malcolmsanford]

I don't think that fluke as the "soft" no trip test for RCDs

 

[white1i]

Hi Malcom

The Robin has a 'd' lock which should prevent the RCD part of the RCBO operating

 

[malcolmsanford]

Fair enough as it as a "d" lock feature then you either have a faulty RCD or meter ?

Have you tried the meter on another RCD?

 

[telectrix]

i have heard thast some RCBOs need the fly lead disconnecting for testing, but i'm not sure if that's for EFLI or RCD test.

 

[Guest112]

ive used a lot of the D locks theyre still not that great on rcds compared to newer testers in my experience and just to be sure your not holding the neutral probe on the earth for any reason because that will trip the rcd aswell