[Kelebek]

Can someone please answer this question for me (and hopefully explain the reasons also).

If I take a television (or for that matter an amplifier or any other piece of AV equipment) to a european country, where 2 pin plugs are the norm, and conect it via a 3 pin adapter, does it matter which way round I plug it in.

If it is not immediately apparent what I mean, in the UK the 3 pin plug always ensures that the live wire from the appliance connects to the live wire in the socket (same with neutral etc) whereas with a 2 pin plug the plug can be inserted either way thus connecting 'live' to 'neutral' and vice versa.

So what happens if the equipment is connected 'the wrong way'? Does it not work? Does it become 'live' and dangerous? If it does'nt matter, why do we bother with different coloured wires?

Clarification and explanation would be greatly appreciated.

[Nigel Goodwin]

Quote:

Originally Posted by Kelebek

Can someone please answer this question for me (and hopefully explain the reasons also).

If I take a television (or for that matter an amplifier or any other piece of AV equipment) to a european country, where 2 pin plugs are the norm, and conect it via a 3 pin adapter, does it matter which way round I plug it in.

No, it doesn't matter, and you have no way of knowing which way it's connected.

Quote:

If it is not immediately apparent what I mean, in the UK the 3 pin plug always ensures that the live wire from the appliance connects to the live wire in the socket (same with neutral etc) whereas with a 2 pin plug the plug can be inserted either way thus connecting 'live' to 'neutral' and vice versa.

So what happens if the equipment is connected 'the wrong way'? Does it not work? Does it become 'live' and dangerous? If it does'nt matter, why do we bother with different coloured wires?

It's generally prefered to switch the live wire rather than the neutral, having coloured wires means it's identifiable for that purpose. On much equipment it makes no difference at all, and NOTHING should be prevented from working, or rendered dangerous, from connecting it the wrong way round.

It's more of a concern for service work, for normal use it's of no consequence at all.

[Kelebek]

Thanks for that reply Nigel.

I feel somewhat reassured now that I am not going to blow anything up!

[bobcar]

As Nigel said unless you open up the box and work inside it then there are no problems with 2 wire equipment. However you should never connect any equipment that's designed to use three wires (2xsupply plus earth) with a socket or adaptor that only has 2 wires - that can be extremely dangerous. Most modern consumer electronics is designed to work with 2 wires but you should check this. (Continental plugs with 2 pins that can plug in either way may very likely have the earth on the sides and are 3 wire and if so are okay).

[Kelebek]

Quote:

Originally Posted by bobcar

As Nigel said unless you open up the box and work inside it then there are no problems with 2 wire equipment. However you should never connect any equipment that's designed to use three wires (2xsupply plus earth) with a socket or adaptor that only has 2 wires - that can be extremely dangerous. Most modern consumer electronics is designed to work with 2 wires but you should check this. (Continental plugs with 2 pins that can plug in either way may very likely have the earth on the sides and are 3 wire and if so are okay).

So are you saying that if I plug a device in via a travel adapter (or similar) that this is extremely dangerous?

[chrisjr]

Quote:

Originally Posted by Kelebek

So are you saying that if I plug a device in via a travel adapter (or similar) that this is extremely dangerous?

Not necessarily. If the device uses the mains earth then that could potentially put you at risk if it develops a fault. The earth is there to prevent metal parts becoming live in such circumstances.

If the device does not have an earth connection then there should be no exposed metal work and extra insulation between you and the mains bits. In which case it is perfectly safe.

A couple of rough ways to check.

If the cable is round then it is more likely to have an earth, though this is by no means certain. Oval or flat cable is more likely to be two core, no earth.

Also a lot of molded on mains plugs have plastic earth pins if there is no earth connection (just there to open the shutters in the socket) A plastic earth pin is a sure sign the equipment has no earth.

If you still have the manuals then there should be a warning in the front if it has to be earthed.

[Nigel Goodwin]

There are two classes of devices, Class I (three wires and earthed), Class II (two wires and double-insulated).

It's fine connecting a Class II device to a two pin socket, but NOT a Class I device - however, it's common practice to do so on the continent.

Don't forget, it's not that many years ago that the UK had two pin sockets, in fact there were a bewildering array of different sockets in use - and still are in some properties. I've known houses where you had to change the plug if you took the vacuum cleaner upstairs.

[Chris Frost]

Quote:

Originally Posted by Nigel Goodwin

I've known houses where you had to change the plug if you took the vacuum cleaner upstairs.

That'll be the gas mantle sockets then, Nigel

It's a odd place, is N. Derbyshire.

[Nigel Goodwin]

Quote:

Originally Posted by Chris Frost

That'll be the gas mantle sockets then, Nigel

It's a odd place, is N. Derbyshire.

Have you ever seen round pin 13A plugs, where one of the pins is a screw-in fuse?