Planning Kitchen Wall Electrics - Is This Good? [PIC]

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Exactly - using the 4mm cable rather then separate legs forces all the accessories on the 4mm cable to be artificially very-close-to-one-another on the ring even when they wouldn't be in the 2x2.5 situation.
Indeed - but, as we know, that is only an issue if one is fairly 'close' to one end of the ring. Once one passes the threshold distance from the ring origin, on can put the entire 32A load at one point of the ring without overloading any cable.

With a 2.5mm² Method C ring, one really does have to get pretty close to one end before there is a problem - since (assuming that the circuit's design current of 32A is not exceeded) the threshold case is 27A down one arm of the ring and just 5A down the other.

Kind Regards, John
 
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Good point didn't think about the higher CCC of method c,
I was just using the minimum 20A, which would be 20a one way and 12a the other.
Thanks I think things are in perspective!
 
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Good point didn't think about the higher CCC of method c, ... I was just using the minimum 20A, which would be 20a one way and 12a the other.
Indeed - but I strongly suspect that, although the regs allow a CCC as low as 20A, a (probably very) high proportion of domestic rings are probably Method C (or as near to Method C as makes no difference to someone with a slightly flexible mind :) ).

Kind Regards, John
 
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Indeed - but, as we know, that is only an issue if one is fairly 'close' to one end of the ring. Once one passes the threshold distance from the ring origin, on can put the entire 32A load at one point of the ring without overloading any cable.

With a 2.5mm² Method C ring, one really does have to get pretty close to one end before there is a problem - since (assuming that the circuit's design current of 32A is not exceeded) the threshold case is 27A down one arm of the ring and just 5A down the other.

Kind Regards, John
I looked at a 32A socket for a welder and initially struggled with the reason one of the 2.5 t&e's was showing signs of overheating but the other was not. This was in a domestic property with a ring covering the whole house [apart from the kitchen] including the garage which was being used as a workshop for metal fabrication. This 32A socket [yellow of course:sneaky:] was less than 2m from the CU. The house was running at around 16A or so when I clamped and the welder around 40A with peaks over 200A [limit of meter], most of the welder current appeared in the short leg of the ring at around 45A. MCB had been changed to D32 to prevent 'false tripping'.
Owner suggested changing the leg of the ring to 6mm² which he had there. I suggested removing said socket from the ring and running it on the spare 40A MCB labelled 'shower'. Following on from there we changed it to C40 and changed socket to 63A isolator.
Point of this story is to demonstrate validity of earlier unbalanced statements.
 
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I looked at a 32A socket for a welder and initially struggled with the reason one of the 2.5 t&e's was showing signs of overheating but the other was not.
There is obviously nothing which is either compliant or sensible about putting a 32A socket on a 32A ring, and even worse when it is for a load such as a welder.
This 32A socket [yellow of course:sneaky:] was less than 2m from the CU. ... most of the welder current appeared in the short leg of the ring at around 45A. MCB had been changed to D32 to prevent 'false tripping'.
Which is, of course, precisely 'as expected'. Do I take it that the Zs was low enough to support a D32?

Kind Regards, John
 
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There is obviously nothing which is either compliant or sensible about putting a 32A socket on a 32A ring, and even worse when it is for a load such as a welder.
Which is, of course, precisely 'as expected'. Do I take it that the Zs was low enough to support a D32?

Kind Regards, John
This was a number of years ago now and my notes long since lost, IIRC we were contemplating using a D40 so I assume a D32 was OK but it was restored to B32 for the repaired ring.
 
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Don't really want to be bumping this thread but don't want to create a new thread about this either...

Can someone tell me if it's OK to "bypass" a socket with cable within a back box like this:

Mkq4JnD.jpg


So 2.5mm on the right drops from a ring but bypasses the first socket within the back box and goes straight to second socket, then another 2.5mm cable goes from second socket back up to top socket, connects in, then out to the ring again.

This would help with the problem DS mentioned about the difficulty of having to terminate 4 cables in a small single socket. It will also mean both these sockets are in the ring, with the bottom one being a spur.

Thanks.
 
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Or you could fit a 35mm box and run it through the back.

As DS says, a spur is fine.

But if you wanted everything on the ring final, you could take one cable to the top socket, one to the bottom socket and the link between them.
 

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