Re: Mains plug restoration
 

The point being made earlier was that an earth pin must be unsleeved. As mentioned earlier (though I can't find the reference) devices that don't require an earth connection need to have either an unconnected earth pin or an Insulated Shutter-Opening Device (ISOD) in order to open these shutters.

Re: Mains plug restoration
 

When it comes to doing PAT testing on anything, it's hard to say whether old plugs need to be replaced or not, it's usually based on risk factors such as whether the plug is used frequently or left plugged in all the time with minimal chances of unplugging it (behind furniture for example), it becomes a case of each engineer to their own by then.
I find it strange how plugs had to have sleeves in the 80's yet it still was not mandatory till about 1993 for plugs to be fitted to stuff, I am only young but can remember certain things being bought with prepared wires only.

Re: Mains plug restoration
 

This gave rise to difficulties when I worked at Woolies. On at least one ocassion a customer bought a lamp and a plug. Once paid for they asked me to fit the plug to the lamp (which I wasn't allowed to do). I've seen so many dangeroulsy wired plugs, I'm also amazed it took so long.

Re: Mains plug restoration
 

I have once acquired some items from a large institution and found a number of badly wired plugs on some of them.

Re: Mains plug restoration
 

I can remember my Mum had a rare unsleeved moulded on plug on her Kenwood Chef, which was replaced when it needed to be repaired to pass the PAT test.

Re: Mains plug restoration
 

The only items I have with moulded-on unsleeved plugs are my BBC Micros. In order to maintain originality, they still have them - whereas everything else in the house has sleeved plugs (either by replacement or from new).

Re: Mains plug restoration
 

The information on sleeved plugs is interesting. I've never seen it written down (I'm not directly involved with BS1363) but it seems there is no requirement to automatically replace a customer plug if it is unsleeved (unless it is cracked or broken of course) so returning the item to the same customer is OK. It's only if the item is resold or if the customer passes it on to someone else that the plug needs to be changed.

When I was doing general servicing and an item came in with an unsleeved plug, I was advised to remove it, fit a sleeved plug and return the old plug to the customer....if they refitted it....fine but when it left our workshop it had a sleeved plug so the onus was on the customer, not us.

Standards can be very confusing!

Re: Mains plug restoration
 

My understanding was always that this rule only applied to someone doing it as a business, be it either a shop selling items or a repair shop etc. that might sell things on to the public and that it didn't apply to the ordinary 'man in the street', either selling, or otherwise passing on an item to someone else.

I have lots of original vintage plugs fitted, but I would agree that as has been said, if infants were to be handling them in any way, then that would be an entirely different story.

Re: Mains plug restoration
 

The text in the link from post no. 14 states:
Incidentally, this is where the reference to ISOD resides that I couldn't find earlier (post 21).

Re: Mains plug restoration
 

That's how I always understood it.

So the 'ordinary' person passing things on with old plugs fitted is exempt.

Re: Mains plug restoration
 

That's certainly my reading of the final sentence, though common sense needs to prevail concerning the condition of the plug.

Re: Mains plug restoration
 

According to the18th edition IET BS7671:2018 regulations section 553.1.1 states:
Every plug and socket outlet shall comply with all the requirements of items (i) and (ii) below and, in addition, with the appropriate requirements of Regulations 553.1.2 to 553.2.2:

i) Except for SELV circuits, it shall not be possible for any pin of a plug to make contact with any live contact of it's associated socket-outlet while any other pin of the plug is completely exposed.

ii) It shall not be possible for any pin of a plug to make contact with any live contact of any socket-outlet within the same installation other than the type of socket-outlet for which the plug is designed.

Bearing in mind that 230v ac is classed as low voltage, not SELV. Indeed the definition of low voltage is defined as being from 50vac to 1000vac.

Hope this extract helps as regard to the regulations.

Dave

Re: Mains plug restoration
 

Well, post #32 kind of muddies the water and justifies the "counterfeit" semi-sleeved earth pin type plug that was lampooned in the link on post #14, if the quote from point (1) of the 18th edition "while any other pin of the plug is completely exposed." is taken literally? The earth pin is always "completely exposed"!

Re: Mains plug restoration
 

Because the earth pin is longer than the other pins, and partially enters its socket before the other pins start to enter theirs, I guess it is already only partially exposed before the other pins start to be inserted. Thus the earth pin can never be "completely exposed" when the other pins start to make electrical contact with their socket contacts.

Re: Mains plug restoration
 

I think that the extract that I posted is more aimed at class II double insulation situations, although that is not specified. All class II equipment that uses a plug should have a completely insulated pin in the traditional metal earth pin location. In general when you purchase this type of gear the mains plug is already moulded on to the supply cable with an insulated pin to operate the internal socket covers via the earth pin hole of the socket. These days though newer socket outlets are designed so that all 3 plug pins have to be inserted before the internal covers move. Also because the phase pins (live and neutral) are part sleeved, it should not be possible to touch the metal parts of these phase pins once being plugged in, as they are already inserted into the socket locator holes and covered before making internal contact with the socket.

Dave

Re: Mains plug restoration
 

Are you saying that it is 'wrong' to fit a normal, rewireable 13A mains plug (with a metal earth pin) to a double-insulated appliance? I was under the impression that this was a reasonable thing to do, you simply don't connect anything to the earth pin inside the plug.

Re: Mains plug restoration
 

I don't believe you are right about an insulated earth pin. I have plenty of stuff around that came with a conventional metal pin. It's not allowed to be partly insulated, though.

Re: Mains plug restoration
 

When I had my shop, I was told by a customer who did electrical inspections, that if a class II plug with plastic earth pin or if the cable fitted to one failed that the whole cable including the moulded plug should be replaced as a complete entity. His argument was that to fit a rewirable plug changed the specification of the equipment. I have since tried to find out if there is anything regulation wise on this but so far have found no further info. It might however be within a BSEN publication. Personally I would weigh up the pros and cons of changing the plug and who I'm doing it for.

Dave

Re: Mains plug restoration
 

This excerpt is from the IET Code of Practice - In-service inspection and testing of electrical equipment - 5th edition, printed 2020. I am presenting this for safe practice information, as it seems to answer a lot of the questions and comments raised and I hope that it all helps to make a bit more sense of a confusing situation. In fact it has cleared up some of my own questions.

Since 1984, BS1363-1 has required the live and neutral pins on newly manufactured plugs to be sleeved. Plugs manufactured prior to 1984 will have solid pins.

There is no legal requirement to change older plugs with solid pins to ones with sleeved pins; however, the dutyholder should consider whether it is appropriate to continue using a plug of that age, and arrange for them to be changed if necessary.

Note that plugs with solid pins, if removed, should not be re-fitted to any items. In addition, items that are sold or hired must be fitted with a plug that meets the current version of BS 1363-1- in particular, second-hand electrical items sold through a charity shop need to be fitted with a new plug if the existing plug has solid pins.

Non-rewirable plugs fitted to Class 2 double insulated items may be manufactured with a non-conducting (usually plastic) pin, which is provided solely for the purposes of opening the socket outlet shutters and confirming polarity. These are often found on small power supply units or phone chargers, which are marked with the double insulation symbol.

Some manufacturers use metal for the earth pin even when not required, as this usually has better physical strength. If a rewirable plug is used (even on a Class 2 item), it should always have a solid metal earth pin.

Dave

Re: Mains plug restoration
 

Glad I'm not the only one who cleans-up earlier plugs.

Quite rightly, it has to be in sound condition/serviceable and correctly fused. A good number of sets around the home & workshop still retain their brown bakelte MK plugs, which have come up a treat. That said & as Paul mentioned, we too ensure the younger members of the family are kept safe.

The Philips Philetta we have, has a very slim/brown bakelite MK plug, which has a plastic arrow held in place by the retaining screw for the cover. This arrow points to a fuse rating which is written/part of the plug moulding. (3A, 7A & 13A if memory serves). Not seen any before or since ...

Some restorations where the plug or non-captive leads are missing, I've made leads from rescued/removable sleeved 'hot-condition' mains plugs from expired toaster & kettles, the beauty is, they look like black bakelite but comply with todays regulations.

On new but cloth covered mains leads, they look the part too.

Mark