Two radials together, when separated it trips dual rcd board.

[down2earth]

I have just installed a new wylex dual rcd board replacing an old memera 2000 single rcd. Whilst wiring in I noticed what was purporting to be a ring main was in fact two radials in the same breaker, no problem I thought, I will split them up, one on each rcd, however, having done that it will occasionally trip both rcd's, I have checked and I haven't got the neutrals round the wrong way, putting both radials on the same side cures the problem. I have yet to do all the testing required but I was wondering if anyone had encountered this before and what the problem was, presumably it is a neutral fault somewhere?

For info I am a Electrical Trainee and this will be checked and notified.

Thanks

D2E

 

[SKY]

Are you 1 million percent sure its 2 radials?

 

[Adam]

To me, it sounds like it is an open ring, and the Neutral is most likely still a ring.

Have you done end to ends on all three conductors for the ring main?

 

[down2earth]

Are you 1 million percent sure its 2 radials?

That's a fair point, when I didn't get any continuity between the Lines I put in a shorting link form Line to earth and tested sockets round the house, one of the radials did one part of the house and the other radial the other half but I suppose if there is a break somewhere this is exactly what you would expect to find

 

[ipf]

Are you 1 million percent sure its 2 radials?

1,000,000%. That would be pretty sure.

 

[Amp David]

If you haven't yet done your testing, then you can't also be sure that these 1 0r 2 circuits are ok in the in res department either.

 

[Johnny-G]

What was the rating of the old MCB protecting the '2 radials'?

 

[ipf]

That's a fair point, when I didn't get any continuity between the Lines I put in a shorting link form Line to earth and tested sockets round the house, one of the radials did one part of the house and the other radial the other half but I suppose if there is a break somewhere this is exactly what you would expect to find

Are you saying you didn't check the circuit fully and made assumptions before you altered the system and made live ?

 

[down2earth]

What was the rating of the old MCB protecting the '2 radials'?

32A :35: woops, the clue is potentially there isn't it.

 

[Johnny-G]

More than likely

 

[ipf]

32A :35: woops, the clue is potentially there isn't it.

That's not all that's 'potentially there' is it ?

 

[ruston]

1,000,000%. That would be pretty sure.[/QUO
Lol better than a like, I love this:lol:

 

[ruston]

Lol looks like you have put the cart before the horse, now the fun starts finding it.

 

[Guitarist]

For info I am a Electrical Trainee and this will be checked and notified.

Thanks

D2E

Do you mean that you will be getting a part P registered electrician to check what you have done, then notify it for you?
With the greatest respect, I would advise you spend some time with an experienced electrician if you are new to the profession. What would you have done without this forum?

 

[bencrockett15]

It must be a ring as both rcds only trip when you borrow a neutral from a circuit that is on a seperate RCD.