Car boot purchase - not safe

[graduate_owner]

Hi all,
I often read about members' bargains from car boot sales, and I have had a few myself. However I bought a couple of used extension leads recently and checked the connections when I got home. One had the earth lead just cut off inside the plug. The other had the live and neutral wires reversed in the trailing socket. Neither was safe, but the scary thing is both would have worked and seemed to be fine.
So I suggest anyone buying used electrical kit should do a check to ensure all is correct, even if the kit does work. In particular, ensure the metalwork on any machine is earthed.

K

 

[andersonec]

You're better off getting some new flex, plugs and sockets from the builders merchants and making up your own, there's no telling if the flex is not damaged inside the insulation.

Andy

 

[Phil Pascoe]

For what most Builder's merchants charge you'd probably do better to buy one off the shelf.

 

[bourbon]

I wouldn't even think about buying an extension lead this way. They are not that expensive new

 

[graduate_owner]

I saw them there for £1 each and thought I would give it a go. I think the important thing though is to warn others who might be tempted. Good point about the insulation too. I will put a megger on the cable just to check.

K

 

[Rorschach]

I always check any electrical items bought at car boots, though to be fair, I rarely buy any.

 

[ChrisR]

I saw them there for £1 each and thought I would give it a go. I think the important thing though is to warn others who might be tempted. Good point about the insulation too. I will put a megger on the cable just to check.

K

A (Megger)/insulation continuity tester will not prove that the earth conductor within the cable can carry a full fault current, it may be just holding on by one strand and the insulation/continuity test will show good. It needs a test with a full fault currant applied, to prove the earth conductor and terminals are in a safe/sound condition.

During my working life as an industrial electrical engineer, I have many times had to provide a report were an earth conductor has failed under a fault condition, because it was of insufficient capacity or it had been damaged prior to the fault occurring. I know I am talking about much larger equipment but the principle is the same.

Take care.

Chris.

 

[graduate_owner]

Hi Chris,
I'm assuming then if I pass say 10A through the cable, by feeding something like an electric fire via the live and earth leads, by deliberately rearranging the wires, then a defective earth wire incapable of carrying the current would show up.

K

 

[ChrisR]

Yes it would, but I would not recommend doing this. The safe way would be using a (PAT) rig.

But I realise that very few people would have access to such a tester, and going to an electrical contractor for this test the cost would probably more than you paid for the cables in the first place, unless you know a friendly sparks who would carry out the test, for the price of a pint.

Take care.

Chris.

 

[graduate_owner]

When it comes to possible cable damage I suppose it applies to the cables on any second hand power tools or machinery. Scary thought really, although I'm sure many if us buy used kit.

K

 

[ChrisR]

You have hit the nail on the head.

Very little domestic electrical equipment gets safety tested from new out of the box, through its working life, to the scrap bin. Unlike, what can be the same equipment, but used in the commercial environment, which will have regular safety tests throughout its working life.

Chris.