Now why didn't I think of that?

[conned tractor]

What is to stop me reversing the polarity of the charge? How much faith would you have in the 1mm of plastic that will stop me twisting it the wrong way? The twist allows leverage to do that and as all real engineers know leverage is the way in which you break things. Also the thing with the flaps off would be easy to twist again when in the socket with leverage and would easily break it.

If the designer had a shot of 240 volts up his arm then he would appreciate why plugs are built that way.

I do admit it is a nice design but simple design is always the best, 240 volts is not a USB type charge.

It 'potentially' wouldn't matter.

[minestrone]

It 'potentially' wouldn't matter.

If someone on here wants to go around their house and reverse the polarity of all the electical devices they have...

[TykeMerc]

You're right Minestrone, that's why I hope he can get Standards approval. There will be some finer design issues that will have to be ironed out.

It would be easy enough to avoid the reversed polarity issue with either a break link if it was rotated the wrong way or an internal connector that only mates if the live is on the right or always connects live to the right. Finer points of design and not hard to engineer.

As you said the UK plug is the worlds safest, it's hard to dislodge and the sockets have a very simple but effective safety design. Assuming this new design meets the right safety standards at some point it could be a huge success.

[conned tractor]

If someone on here wants to go around their house and reverse the polarity of all the electical devices they have...

It was a joke - 'potential'.

Trying to think back to psu design. I think most of it should still work - any sparky types about. OK just foundthe following - possible but not necessarily safe.

"Reverse polarity" is the term used to describe a situation where electrical wires are connected to the wrong terminals of a receptacle. It can be hazardous if the "hot" side of your electrical system gets connected to certain types of lamps or equipment.

It's a common condition because it's an easy mistake to make when hooking up wires and because receptacles work fine even when the polarity is reversed. You generally don't know the condition exists unless you look for it."

Anyhow, I should imagine the plug doesn't necessarilt have permanent conection to a single pin but a contact is made upon the swivel action meaning that incorrect polarity would not happen. I would be more worryed about arcing contacts though. (Although I dont know the internal workings and am guessing).

And I dont think this would make it through any heat type or high current standards so low power only. Good idea for mobile equipment though.

[TykeMerc]

And I dont think this would make it through any heat type or high current standards so low power only. Good idea for mobile equipment though.

True to an extent, it would depend on the materials used.

Of course for higher power applications the devices tend to come with bonded plugs and aren't generally that portable or small so using a current design plug wouldn't be a disadvantage.
I got a mains charger with a camera a couple of years ago that presents as USB so will take any USB charge lead and came with a couple of types of slot on connectors for different regions of the world, again an elegant solution for people who travel and of course it means the manufacturer only produces one universal charger so saving money, quite an elegant solution to what can be a pain in the nads.

[gingerjedi]

Correct me if I'm wrong but AC current doesn't have 'polarity' so it wouldn't mater which way it was twisted.

[conned tractor]

True to an extent, it would depend on the materials used.

I learnt that lesson not so long ago. I wired up a home made bodge job heating vessel with a 2.4KW element - stolen from a cheap asda kettle. Now although most kettles are cordless, inside the kettle the element still has the prongs for the plug. So, knowing not to use a computer lead went about the house looking for a suitable 'kettle' type lead. Found one with a moulded plug rated at 10 amps and moulded connection at the kettle end at 13 amps (or the other way around). Thought this would do as it would only be carrying 10 amps-ish through the wire.

When the wire started to melt on the worksurface started to panic a bit but no real harm done.

Later found out that there is also a heat rating for such connectors and as an electronic engineer suffered at first to get my head round it. Apparantly, according to the sparky types, it is the conducted heat back through the cable that causes it to melt and not the actual current itself. Although obviously it helps to heat it.

[minestrone]

It was a joke - 'potential'.

Trying to think back to psu design. I think most of it should still work - any sparky types about. OK just foundthe following - possible but not necessarily safe.



Anyhow, I should imagine the plug doesn't necessarilt have permanent conection to a single pin but a contact is made upon the swivel action meaning that incorrect polarity would not happen. I would be more worryed about arcing contacts though. (Although I dont know the internal workings and am guessing).

And I dont think this would make it through any heat type or high current standards so low power only. Good idea for mobile equipment though.

Knew it was a joke, honest, I left the question there for the rest of the board.

I reversed the polarity when trying to fix my ZX Spectrum once and pfffxxstt was the noise I heard. No more jet set willy for me.

Can I just say the chap could have used a nail brush before the photo shoot. God knows where that lad has put his thumb judging by the colour of it. Instant job fail for me if he came to an interview.

[minestrone]

The times I see something like that being useful is in a laptop bag but when the plug size is incidental to the power adapter it is attached to it is meaningless. Even the mac I have in the house has a box about 4 times the size of the plug. My laptop dell has a potenital murder weapon sized power adapter.

Looking under my desk I can see about 5 of these things.

[Platypus]

Correct me if I'm wrong but AC current doesn't have 'polarity' so it wouldn't mater which way it was twisted.

That's what I was thinking too, and how come the Yanks don't have a polarity problem with their easily reversible plugs?