Wrong size cable.

30 Jun 2008
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United Kingdom
We have a contractor in work carrying out PAT work. He has failed an appliance which, whilst not strictly being portable in that you can carry it around, is connected via a BS1363 plug.
His reason is that the 2.5mm 3 core cable is too large for this plug and the maximum diameter should be 1.5mm

Is this correct and is he right to fail it?
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Correctly speaking, a 13A plug is not designed for a cable bigger than 1.5mm². But he is being a bit regimentally insane to fail it if this is the only reason and its not down to a another reason related to the flex instead. Such as it being fitted with such a flex becuase the load is >13A. (its not an arc welder is it??) Or the installer not managing to get the cable in the plug and use the cord grip properly?

Who is doing the PAT testing? A PAT company, or a sparks?
Well, it's not ideal, as it is pretty big to fit into a plug, that being said - if it's done tidily and correctly you can't fail it.

What is it and why does it have 2.5 on it?
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What is the purpose of the PAT?

Is it to ensure that the item is safe?

Does a larger cable render the item unsafe?

The flex itself is surely safer being larger.

It makes no difference to the appliance.

It makes no difference to the plug.

Q.E.D. ???
Does a larger cable render the item unsafe?
As has been said, it could if, say, the size of the cable precluded using the cable grip satisfactorily - but, other than that, I agree that there would appear to be no problem.

Kind Regards, John
If the appliance was manufactured with a 2.5mm² flex it probably isn't designed for connection to a 13A plug. Just like the glasswasher I posted recently that had a 4.0mm² flex jammed into a 13A plug.
11mm. is quite large.
It is, and that may well include many/most 2.5mm² flexible cables, but the situation is theoretically complicated by the fact that, for whatever reason (terminal capacity??) they also specify a maximum CSA of 1.5mm².

Kind Regards, John
Do you consider the 1.5mm² an instruction or merely information?
If an instruction, then for what reason?

Would it be heresy to suggest that the strands could be cut to accommodate the conductor?

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