The other morning I went to plug in a piece of equipment on my work bench. It needed a standard IEC-type power cable. My workshop, like many others, has a box in the corner containing an assortment of such power cables. I can’t remember where most of them came from, and I just grabbed the first one.
It seemed rather short, only about one metre long. That didn’t matter for this job. But I noticed that the insulation was damaged near the IEC connector. Oh dear. That makes the cable unsafe to use, so I set about destroying it before throwing the parts away. My usual technique for that is to put one foot on the plug and pull hard, tearing the cable out and rendering the whole thing unusable scrap. But I got a surprise: the cable more or less came apart in my hands!
I examined it more closely and found the oddest colour code I’ve ever seen:
Where on earth is the mains wiring colour code blue, black and black with a turquoise stripe? Not anywhere in Europe, that’s for sure. I looked further, taking the fuse out of the plug. Sharp-eyed readers will already have noted that the fuse is rated at 3A but coloured brown. That’s an oxymoron: under the British Standard BS1362, 3A fuses are red and 13A fuses are brown. So which was this one? It certainly doesn’t comply with the standard in spite of the ‘BS1362’ written on it.
Time to test the fuse. I hooked it up to my big power supply, and cranked up the current.
Yes, you read it right. This fuse labelled ‘3A’ carried 26.6A for long enough for me to pose it for a photo, pick up the camera and press the button. It blew a few seconds later. That’s the sort of behaviour I’d expect from a 13A fuse, not a 3A one. Oh dear.
I went back to the cable, and noticed that I could easily pull apart the insulation – both the thick outer and the inner cores – with my bare hands. No tools required, not even fingernails. That’s unbelievably dangerous. Once I’d peeled some insulation off, there was hardly any copper inside the wires:
My finger-in-the-air estimate of the safe current carrying capacity of this wire would be less than 1A.
What a cable. The connectors on both ends (which I forgot to take a photo of) were covered with various approval logos. I can’t believe this thing met any safety standards. The wire itself was so weak that it could be peeled back to bare copper with just my fingers. The plug fuse was mislabelled and far too large for the rating of the cable. The cable was so thin it wouldn’t handle the load that an IEC connector is designed for without dangerously overheating. If a fault had developed in the appliance plugged in with this cable, it’s likely that the cable would simply have caught fire before the fuse blew.
I believe that this cable was supplied with a Chinese USB hard drive enclosure I bought a few weeks ago, but I can’t prove it. If you buy cheap electrical goods, check the mains cable carefully. I don’t know whether to call this one fake, counterfeit or just bad, but it was certainly a death trap.
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