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AIUI the socket *must* be rated to 13A to comply with BS1363

That's the impression I was under as well, but I'm really not sure about the contacts on that socket being able to take that current continuously. There were no clues as to the manufacturer or country of origin on this socket.


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Is the heater plug cracked or was that a hair on the lens?
It wasn't cracked -- Must have been a hair.

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A 3A Extension lead??!!. Why such a small rating?.

As I said, my guess would be that this socket started out life on an extension cord sold for garden tools. It would probably have had orange flex, and most likely an orange plug too, fitted with a 3A fuse. You can still buy extension cords using 0.75 sq. mm flex fused at 3 or 5A.

The plug I found on the other end of this extension was just a generic white type, fused at 13A.

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Fibreboard composition, [or 'compo' as it was known], is a pressed resin/woodfibre material of immense strength when dry.

Yep, the old fiber cord grips are actually much stronger than they look. The usual failure is where someone has been a little over-enthusiastic about tightening them and stripped out the threads.

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Historical note: The British Army issued our squaddies with 'compo' ID dog-tags during WW2 for economy.

I've read that in the U.S. a couple of states issued fiber license plates for cars during WWII as well to save metal. Apparently people in one area had problems with wild goats deciding that these made a tasty snack!

"No license plate officer? Gee, a wild animal must have eaten it!" [Linked Image]