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Comment by cstross | Hacker News Reader

There's also a second reason British plugs are robust and fused: they're built to carry up to 3 kilowatts at 230 volts. (None of your wimpish American 110 volt mains juice here! Nothing quite makes your hair stand on end like accidentally touching a live pin carrying 230 volts and 13 amps ...)

To that end, the live and neutral contacts in a British socket are shuttered. The long earth pin on the plug makes contact before the live or neutral pins are in the socket, and once in contact, raises a shutter to permit live and neutral to make contact. And the nether regions of those pins are insulated so that if a plug is halfway into a socket and something bridges the pins, it can't make contact.

This is a great design -- for space heaters and ovens and server racks. It's a bit less useful for the low power consumption devices that have come to dominate the market (where maximum draw is well under 1Kw -- often under 0.1Kw).

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> There's also a second reason British plugs are robust and fused: they're built to carry up to 3 kilowatts at 230 volts. (None of your wimpish American 110 volt mains juice here! Nothing quite makes your hair stand on end like accidentally touching a live pin carrying 230 volts and 13 amps ...)

Mainland european grounded plugs pretty much all handle 15A/230V, and none looks like a battlecruiser (see the well-known and widely used "CEE 7/7" aka "Type E/F hybrid": http://en.wikipedia.org/wiki/File:CEE_7-7.jpg)

And the nether regions of those pins are insulated so that if a plug is halfway into a socket and something bridges the pins, it can't make contact.

That's not really true, you can still get electrocuted if you put you finger on both bolts.

And that plug is massive. Luckily you can use any sticklike thing to allow continental plugs to be inserted (which incidentally I'm doing right now -- hello from Edinburgh)

The L+N pins are insulated half way down so you can't touch any metal part that is in contact with the supply. The supply terminals are also covered by shutters so you can't put anything in them when there is no plug in the wall.

Australian plugs carry 15A at 240V and are nowhere near as horrible.

Australian plugs aren't designed to carry any significant physical weight, as far as I could tell (I was in Melbourne a month ago). The thickness of the live and neutral blades is similar to that of American/Japanese plugs, rather than the round pins common in the EU or the rectangular cross-section pins used in the UK. On the other hand? "Nowhere near as horrible" fits the bill for about 95% of purposes -- because nobody should be expecting a 230 volt mains plug and socket to double as a structural support!

Not at all. NZ plugs are the same design as Australian ones and mine seem quite capable of carrying a reasonable amount of weight - I have never ever seen one of our plugs fail under anything resembling sensible use. They're quite capable of carrying, say, a hefty attached transformer.

And since the pins are angled, even a two-pin version is pretty hard to accidentally wiggle free compared to the two round pin European plug (I think some European countries have extra bits as well that might help?). Definitely does not deserve comparison to the awful American plug design.

It does, however, mean that any type of appliance that you might wish to plug in uses the same plug, regardless of what power level it wants - quite a good example of It Just Works, even if the price you pay is huge plugs.

Of course, that does break down a bit when you get to fuses, since you now have to worry about using different capacity fuses for appliances with different expected maximum power draw (3A for most things, 5A for the odd high-power small appliance, 13A for anything involving a heater...)

Actually, UK buildings typically contain at least three different standard sockets and plugs--the big ugly ones (with a supply of four different fuses needed), a mini version of that design commonly used for table lamps and floor lamps, and a third design allowed in bathrooms so you can plug in an electric shaver (electrical sockets and even light switches are ordinarily barred from bathrooms). There are also many different kinds of lightbulbs (screw-in, push-in, push-and-turn-to-lock-two pins) in many different physical sizes (as well as different wattages). Running a family house requires a considerable stock of bulbs and fuses, which explains all the "electrical supplies" shops which are unknown in the US. Up until about 10 years ago, in my personal experience, UK small appliances, lamps, etc. were sold with bare AC wires and the householder was expected to add the needed style of plug; now everything comes with the huge plugs.

What are these mini plugs? Everything I've ever seen has either the BFO plugs or the wee razor type plugs that go into the BFO ones with an adaptor. I've never seen a socket in a house for razor type plugs (although hotels do have them) - I guess new properties might have them.

WRT the "mini version" you are thinking of the pre-WWII BS 546. BS 1363 was introduced in 1947 and does not have a mini version.

UK buildings typically contain

I've only ever lived in houses with the big uglies.

All lightbulb headaches have been due to IKEA and their foreign ways.

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