Electrical mains question - not really boaty...

PetiteFleur

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Do mains powered appliances, say electric drills have to be fitted with insulated L & N plugs? Even if old ones before the regs changed? If a new lead is fitted should it also have a new plug? Will it fail a PAT test with old plugs?
 
I presume you mean sleeved L and N pins on the 13A plug.
No idea whether an old plug should fail PAT.
FWIW, you can still buy 5A round pin plugs with unsleeved pins...
PAT testers sometimes live in a world of their own, years ago my Anglepoise light went off to be tested at a large UK electronics firm, it eventually came back with about 6 earth straps bonding the various bits together!

I would suspect fitting an old plug to a new lead is verboten and only card-carrying sparks might be allowed to change a lead.
 
I thought you might have been asking a bout doubly insualted appliances which dont need an earth connection or about moulded-on plugs

Assuming TernVI has understood correctly and you were actually asking about sleeved vs non sleeved pin plugs this is relevant information

BS1363 Non-Sleeved Plugs
 
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It won't fail a PAT test unless the plug is faulty. It might well fail an electrical safety inspection though :)

Viz the anglepoise lamp, i once PAT tested an elderly metal one and indeed it was a case of either bin it or electrically bond each of the metal arms back to earth because it failed dismally (any exposed metalwork HAS to be earthed otherwise it could potentially become live and lethal. There was no electrical connection at all between any of the exposed metalwork. It was toast which was marginally preferable to the owner being toast!)
 
It won't fail a PAT test unless the plug is faulty. It might well fail an electrical safety inspection though :)

Viz the anglepoise lamp, i once PAT tested an elderly metal one and indeed it was a case of either bin it or electrically bond each of the metal arms back to earth because it failed dismally (any exposed metalwork HAS to be earthed otherwise it could potentially become live and lethal. There was no electrical connection at all between any of the exposed metalwork. It was toast which was marginally preferable to the owner being toast!)
That's untrue.
It was marked as double insulated.
Lots of things have exposed metal work which is not earthed.
I have right here a Bosch power drill. The earth pin of the plug is plastic and the chuck is metal.
Clearly the chuck is not earthed.

I had a lot of fun faxing the compliance director at Anglepoise and getting him to send a terse response to the site electrician's boss.

Electricians mostly operate by rote learning and make mistakes as soon as they're off their familiar territory.
 
That's untrue.
It was marked as double insulated.
Lots of things have exposed metal work which is not earthed.
I have right here a Bosch power drill. The earth pin of the plug is plastic and the chuck is metal.
Clearly the chuck is not earthed.

I had a lot of fun faxing the compliance director at Anglepoise and getting him to send a terse response to the site electrician's boss.

Electricians mostly operate by rote learning and make mistakes as soon as they're off their familiar territory.

I didn't say it was or wasn't true! The ancient one i was testing wasn't double insulated and you hadn't mentioned that bit! Makes all the difference does that
 
I would fail an appliance with uninsulated L & N pins on the plug. Don't know chapter and verse regarding the regs but it is many years since insulated pins came in and there aren't many uninsulated ones around now. Cost of replacement minimal.

Too easy for someone to touch the pins whilst the plug is partially inserted.
 
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Is the correct answer !

The unsheathed terminals run the risk of being held in the same hand whilst being inserted into the socket.
Would have failed a PA Test 25 years ago.

Old trick of supergluing an old 2p in-between the three pins and asking gullable apprentice to plug item in was an age old trick back when I qualified in 1990 ;)
 
I would fail an appliance with uninsulated L & N pins on the plug. Don't know chapter and verse regarding the regs but it is many years since insulated pins came in and there aren't many uninsulated ones around now. Cost of replacement minimal.

Too easy for someone to touch the pins whilst the plug is partially inserted.
Is the correct answer !

The unsheathed terminals run the risk of being held in the same hand whilst being inserted into the socket.
Would have failed a PA Test 25 years ago.

Old trick of supergluing an old 2p in-between the three pins and asking gullable apprentice to plug item in was an age old trick back when I qualified in 1990 ;)

There is no requirement to replace plugs with non-sleeved line and neutral pins. ((IET Code of Practice, page 138, table VII.1 section 15) except on equipment which is to be hired out, offered for sale or are included in rental accommodation ( Plug & Sockets etc. (Safety) Regulations 1994. )
 
For the sake of £1 to buy a new plug is it worth the risk?
99% of PA tests are in an industrial /commercial environment.(PUWER Regs)
Very few are carried out in homes other than rental properties.
In all of these instance it would fail a PA test.
 
All my wall sockets are switched, aren't most peoples' in the UK?

Using the switch removes the danger.
1. Not all wall sockets are switched.
2. Not all wall sockets with switches are switched off when the plug is inserted or removed. (Laziness, accidentally operating the switch, mistakenly operating the wrong switch in a double socket.)
3. Appliances are not only plugged into/unplugged from wall sockets but also extension leads/power strips and adaptors of various kinds.
Any safety device which requires human action to be effective is inherently less safe than one which does not.
 
I wonder how many people actually managed to get shocks from unsleeved plug pins?

Any un sleeved pin 13A plug is pretty old now. Wouldn't hurt to open it and check the screws are still tight etc.
While you're doing that, might as well change it.

But of course you will need a card-carrying sparks to change it in many circumstances.
You may object to that, but on looking at some of the plugs on things inherited from my Dad, there may be a point to such rules....
 
I wonder how many people actually managed to get shocks from unsleeved plug pins?

ITYWF that when the plug is inserted into a socket far enough for the pins to make contact there is not sufficient space between the plug and the socket to reach the pins with a finger and thumb, except perhaps for some badly designed cheap ones , which may not in any case comply with the relevant standards.

I was going to investigate but your post has prompted an earlier reply.

I probably have a number of non-sleeved pin plugs in use and I would be pretty miffed if some backstreet cowboy electrician removed good quality MK plugs and replaced them with £1 junk for no valid reason
 
ITYWF that when the plug is inserted into a socket far enough for the pins to make contact there is not sufficient space between the plug and the socket to reach the pins with a finger and thumb.....

I've just measured, 8mm of insulated sleeve on the pins. So possibly a child's fingers would make contact. The insulation also stops improvised extensions with wires twisted round the pins.
 
I've just measured, 8mm of insulated sleeve on the pins. So possibly a child's fingers would make contact. The insulation also stops improvised extensions with wires twisted round the pins.
That's not quite what I meant.

Push the plug into the socket until the pins just make contact. Now measure the gap between the plug and the face of the socket.

I've now tried several different plug and socket combinations and am finding only about 5mm .
 
That's not quite what I meant.

Push the plug into the socket until the pins just make contact. Now measure the gap between the plug and the face of the socket.

I've now tried several different plug and socket combinations and am finding only about 5mm .
This experiment reminds me of the one where, so I was told, a factory inspector couldn't understand how a machinist lost a finger.... so the foreman showed him, and lost one of his.

Turn the electric off first maybe?
 
Turn the electric off first maybe?
You could use a table lamp or similar, slowly insert the plug into a switched on socket until it lights. Switch off the power then measure the gap with a non conducting rule.
But that would be not only incredibly dangerous and foolhardy but irresponsible to suggest to the t.....s who read these forums.

The way to do it is with a completely disconnected plug and socket and a multimeter on an ohms or continuity range.
 
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