earthing a new double socket

[ban-all-sheds]

There's a problem here:

the cable supplying the original double socket is about 2.5mm to look at.

not sure which supply exiting the CU goes to heating but all are around 2.5mm.

Not sure why, at the time, you thought the cables were "2.5mm", but you now seem pretty definite that the largest dimension is 4mm.

If so that makes it 1mm² cable - no way should that be on a 32A breaker.

 

[JohnW2]

.... you now seem pretty definite that the largest dimension is 4mm.
If so that makes it 1mm² cable - no way should that be on a 32A breaker.

I'm getting very confused by all this. As you say, the op is now saying that the largest dimension is 4mm, which is not really credibly for any T&E cable. Despite what you say, that would actually be only about half the size of even 1mm² T&E.

I wonder if this is just measurement error (seems a large error for that) or whether we don't understand what the op is measuring (maybe just one conductor+insulation?), particularly given that 'the chances are' (although I'm placing no bets!) that the cable is actually 2.5mm².

Kind Regards, John.

 

[ban-all-sheds]

.... you now seem pretty definite that the largest dimension is 4mm.
If so that makes it 1mm² cable - no way should that be on a 32A breaker.

I'm getting very confused by all this. As you say, the op is now saying that the largest dimension is 4mm, which is not really credibly for any T&E cable. Despite what you say, that would actually be only about half the size of even 1mm² T&E.

Quite right.

'tis the thickness of 1mm² T/E which is 4mm, not the width.

Dunno what I was thinking of.

I wonder if this is just measurement error (seems a large error for that) or whether we don't understand what the op is measuring (maybe just one conductor+insulation?),

the tricord from the CU is 4mm.

tried to measure the widest part of the cable.

particularly given that 'the chances are' (although I'm placing no bets!) that the cable is actually 2.5mm².

Let's hope so.

He keeps calling it "tricord". Let's hope it's not 3-core flex with an OD of 4mm.....

 

[JohnW2]

He keeps calling it "tricord". Let's hope it's not 3-core flex with an OD of 4mm.....

I seriously doubt that you'd find any LV-rated 3-core flex that small (only ELV 'signal' or 'alarm' cable) - even 0.5mm² 3-core flex usually has an OD of 5.5mm or 6.0mm!

I think we need a photo or two!

Kind Regards, John.

 

[Adam_151]

I'm guessing he must be talking over core and insulation, so 4mm would be just over 4mm² (which if memory serves has a diameter over insulation of 3.7mm), so perhaps its old 7/0.036, but we are just guessing!!

 

[JohnW2]

I'm guessing he must be talking over core and insulation, so 4mm would be just over 4mm² (which if memory serves has a diameter over insulation of 3.7mm), so perhaps its old 7/0.036, but we are just guessing!!

Yes, I did suggest that as a possibility a couple of posts back, but one wouldn't expect to see references to the 'maximum dimension' for an essentially round conductor+insulation. As you say, we're guessing all over the place!

Kind Regards, John

 

[ban-all-sheds]

I move that we all just go away until the OP gets back with more info.