Strange plugs & sockets at Lewis's Liverpool - Page 2 - UK Vintage Radio Repair and Restoration Discussion Forum

Tim · 29th Nov 2009, 12:31 am

We have some at work which have the L&N of a standard 13 amp plug, but a ROUND earth pin, as you would expect to see on the old 15 amp size. They are fused and are identical to standard bs1363 plugs otherwise(in fact I suspect they have been modified from same)
We had some Walsall gauge in the school science lab when I was a lad. I think these were all protected by a 30 mA trip, or were isolated or something.

cmjones01 · 29th Nov 2009, 1:17 am

There seems to be an infinite variety of non-standard 13-amp-like mains plugs. Our school science labs had some (made by Dorman Smith, if I remember rightly) which were exactly like 13-amp plugs but with the live pin at 90 degrees to its usual orientation. The application of a craft knife to the live holes of a cheapo 4-way extension lead allowed them to fit! They were all fed from an isolating transformer at the front of the lab. Good thing too, with that kind of bodgery around...

Tractorfan · 29th Nov 2009, 8:54 pm

Hi all,
It looks like the plugs & sockets in my original post were Wandsworth types very similar to those in Russell W B's post no.16. In Lewis's I don't think they were for any special supply as they were everywhere including the floors & ceilings! I posted the same query on Electroteknica's forum too and a reply contained an illustration from an old catalogue showing something almost exactly the thing I was thinking of.
All the other plugs discussed here are interesting too and I would be curious to find out exactly how many variants there are of the standard 13amp design. I think Britmac as well as Walsall were famous for those.
Thanks for all your replies.
Cheers de Pete

kalee20 · 29th Nov 2009, 9:17 pm

One of my schools (Ysgol Y Gader, Dolgellau) had a physics lab built in the 1960's, this had mains supply via Walsall sockets. As far as I know, these weren't fed via a big isolating transformer. My physics teacher commented to me that he'd never come across them.

Obvious question is: Who sells the mating plugs? (The school at that time - mid 1970's - had sufficient for its needs)

dseymo1 · 29th Nov 2009, 11:14 pm

RS sell a couple of versions - the round earth pin type, and one with a sort of T profile earth. I suspect that most of the big electrical factors carry a range.

BTW, I've come across these in hospitals too, for use with X-ray gear, and also for circuits intended for critical equipment (possibly to stop the cleaners unplugging it when vacuum cleaning, but more likely because they are maintained supplies, or have dedicated earths).

Phil G4SPZ · 30th Nov 2009, 1:07 am

I recall seeing plugs with 90 degree rotated earth pins in old hospitals, too, as well as normal-looking BS1363 plugs with a notch in the earth pin. These were for use with sparkless sockets which were interlocked mechanically to prevent the plug being inserted or withdrawn with the socket live. The on-off switches were mercury-bottle tilt switches.

These were developed to prevent explosions and messy fatalities when flammable anaesthetic gases were used in operating theatres. Don't worry, ether and chloroform have been replaced by safer alternatives nowadays, but the anti-static precautions still remain. In the 1970s we still used to megger-test floors, rubber tyres on trolleys and rubber hoses, all made from conductive materials in those days of course.

Tractorfan · 30th Nov 2009, 9:55 pm

Yes, I remember those mercury switched sockets at the hospital I worked at, They were made by Walsall. The matching plugs were marked "Theatre Use Only". The light switches were mercury types too. Also, there were special non-fused 13amp gauge plugs with standard pins and an extra large cable outlet for portable X-ray machines.
Cheers de Pete

Nickthedentist · 30th Nov 2009, 10:16 pm

Quote:

Originally Posted by Tractorfan

Also, there were special non-fused 13amp gauge plugs with standard pins and an extra large cable outlet
...

Shhh, don't tell the audiophools

Tractorfan · 30th Nov 2009, 10:44 pm

Ok, I won't.

russell_w_b · 1st Dec 2009, 9:58 am

Quote:

Originally Posted by Tractorfan

'All the other plugs discussed here are interesting too and I would be curious to find out exactly how many variants there are of the standard 13amp design. I think Britmac as well as Walsall were famous for those.
Thanks for all your replies.'

There are many 'legacy' plugs still used in industry (Walsall, Reyrolle, Niphan, Simplex, etc...) but there seems to be a trend towards those to BS4343 (now IEC 60309) for new equipment.

Of course, these are wildly different to what, at first glance, appears to be a normal domestic plug to BS1363, and I guess these are the ones you're interested in. To this end, I attach a photo of a fused 13A 'Walsall'-gauge plug, for the benefit of those who have never come across one. We use fused and unfused variants at work, with the unfused ones having sockets fed individually from suitably-rated fuses in a distribution board, and used on 'fixed' equipment, like 19" bays.

Note the lettering on the plug: 'Not for Domestic Use'.

29th Nov 2009, 12:31 am	#21
Tim Dekatron Join Date: Jan 2003 Location: Bradford on Avon, Wiltshire, UK. Posts: 3,310	Re: Strange plugs & sockets at Lewis's Liverpool We have some at work which have the L&N of a standard 13 amp plug, but a ROUND earth pin, as you would expect to see on the old 15 amp size. They are fused and are identical to standard bs1363 plugs otherwise(in fact I suspect they have been modified from same) We had some Walsall gauge in the school science lab when I was a lad. I think these were all protected by a 30 mA trip, or were isolated or something. __________________ "Nothing is as dangerous as being too modern;one is apt to grow old fashioned quite suddenly."

29th Nov 2009, 1:17 am	#22
cmjones01 Nonode Join Date: Oct 2008 Location: Warsaw, Poland and Cambridge, UK Posts: 2,677	Re: Strange plugs & sockets at Lewis's Liverpool There seems to be an infinite variety of non-standard 13-amp-like mains plugs. Our school science labs had some (made by Dorman Smith, if I remember rightly) which were exactly like 13-amp plugs but with the live pin at 90 degrees to its usual orientation. The application of a craft knife to the live holes of a cheapo 4-way extension lead allowed them to fit! They were all fed from an isolating transformer at the front of the lab. Good thing too, with that kind of bodgery around...

29th Nov 2009, 8:54 pm	#23
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,182	Re: Strange plugs & sockets at Lewis's Liverpool Hi all, It looks like the plugs & sockets in my original post were Wandsworth types very similar to those in Russell W B's post no.16. In Lewis's I don't think they were for any special supply as they were everywhere including the floors & ceilings! I posted the same query on Electroteknica's forum too and a reply contained an illustration from an old catalogue showing something almost exactly the thing I was thinking of. All the other plugs discussed here are interesting too and I would be curious to find out exactly how many variants there are of the standard 13amp design. I think Britmac as well as Walsall were famous for those. Thanks for all your replies. Cheers de Pete __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

29th Nov 2009, 9:17 pm	#24
kalee20 Dekatron Join Date: Feb 2007 Location: Lynton, N. Devon, UK. Posts: 7,078	Re: Strange plugs & sockets at Lewis's Liverpool One of my schools (Ysgol Y Gader, Dolgellau) had a physics lab built in the 1960's, this had mains supply via Walsall sockets. As far as I know, these weren't fed via a big isolating transformer. My physics teacher commented to me that he'd never come across them. Obvious question is: Who sells the mating plugs? (The school at that time - mid 1970's - had sufficient for its needs)

29th Nov 2009, 11:14 pm	#25
dseymo1 Retired Dormant Member Join Date: Dec 2007 Location: Shropshire, UK. Posts: 3,051	Re: Strange plugs & sockets at Lewis's Liverpool RS sell a couple of versions - the round earth pin type, and one with a sort of T profile earth. I suspect that most of the big electrical factors carry a range. BTW, I've come across these in hospitals too, for use with X-ray gear, and also for circuits intended for critical equipment (possibly to stop the cleaners unplugging it when vacuum cleaning, but more likely because they are maintained supplies, or have dedicated earths).

30th Nov 2009, 1:07 am	#26
Phil G4SPZ Dekatron Join Date: Apr 2005 Location: Bewdley, Worcestershire, UK. Posts: 4,748	Re: Strange plugs & sockets at Lewis's Liverpool I recall seeing plugs with 90 degree rotated earth pins in old hospitals, too, as well as normal-looking BS1363 plugs with a notch in the earth pin. These were for use with sparkless sockets which were interlocked mechanically to prevent the plug being inserted or withdrawn with the socket live. The on-off switches were mercury-bottle tilt switches. These were developed to prevent explosions and messy fatalities when flammable anaesthetic gases were used in operating theatres. Don't worry, ether and chloroform have been replaced by safer alternatives nowadays, but the anti-static precautions still remain. In the 1970s we still used to megger-test floors, rubber tyres on trolleys and rubber hoses, all made from conductive materials in those days of course. __________________ Phil Optimist [n]: One who is not in possession of the full facts

30th Nov 2009, 9:55 pm	#27
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,182	Re: Strange plugs & sockets at Lewis's Liverpool Yes, I remember those mercury switched sockets at the hospital I worked at, They were made by Walsall. The matching plugs were marked "Theatre Use Only". The light switches were mercury types too. Also, there were special non-fused 13amp gauge plugs with standard pins and an extra large cable outlet for portable X-ray machines. Cheers de Pete __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

30th Nov 2009, 10:44 pm	#29
Tractorfan Dekatron Join Date: Mar 2008 Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.) Posts: 3,182	Re: Strange plugs & sockets at Lewis's Liverpool Ok, I won't. __________________ "Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."