radial trips rcd, but not on rcd side

by **danny001** » Tue Feb 26, 2008 3:03 pm

hi,
in my fuse box i have the main switch and a few mcb then a rcd and 2 more mcb,

a 20a mcb when turned on ( which is on the non- rcd side ) will trip the rcd,

can anybody tell me why and a fix as i cant see how it can trip the rcd when its not on the rcd side

many thanks danny

by **sparx** » Tue Feb 26, 2008 5:18 pm

Hi Danny,
bet the neutral is on the RCD side!
look at the 2 neutral bars and count cables on each and compare with number of lives on each half of board. IE 5 lives on RCD half of board should have 5 Neutrals on RCD side of Neutral bar. RCD is looking for balance so if one circuit is on wrong half the return current will bypass it & it will do it's job,
Regards SPARX

by **danny001** » Sat Mar 01, 2008 9:29 am

hi,
thanks just sorted it out it was both 20a mcbs
each of the Neutral where on the rcd side

many thanks it would be one thing that did not crosss my mind