New outside ring main -RCD tripping

[snico1974]

Fitted some new outdoor sockets, however on connecting cables to fuse box RCD keeps tripping

Had already wired up the MCB to the fuse box before hand, so simply a matter of connecting cables via connector blocks...so I thought.

Nothing is plugged into the circuit.

What's confusing me is the the MCB is switched off - so I can't under why it would trip

Can anyone offer a few pointers?

 

[electronicsuk]

If it occurs when the MCB is off then it follows that only earth and neutral will (read: should) still be connected. If that's the case then it could well be a Neutral-Earth fault.

Pictures?

 

[tjsparks]

Fitted some new outdoor sockets, however on connecting cables to fuse box RCD keeps tripping

Had already wired up the MCB to the fuse box before hand, so simply a matter of connecting cables via connector blocks...so I thought.

Nothing is plugged into the circuit.

What's confusing me is the the MCB is switched off - so I can't under why it would trip

Can anyone offer a few pointers?

probably a borrowed neutral somewhere?

 

[electronicsuk]

Maybe, but then it would seem odd that the fault occurs with no load on the circuit and the MCB switched off. No disrespect to the OP, but the mention of an outdoor socket ring is ringing alarm bells, this is probably why there have only been a couple of replies to your thread.

 

[davelx]

Why odd? The earth and neutral are still connected to all the other circuits. If there is an E-N fault, then some of the neutral current from other circuits will flow back via the E-N fault, and if high enough will trip the RCD