ECN Forum Forums General Topics of the Trade Non-US Electrical Systems & Trades BS317:1928 question

I've tried a search on this British Standard, but with no information other than it was replaced by the BS546:1950 standard for the round-pin plugs and sockets.

I wonder if anyone could tell me if this earlier standard was much different from the 1950 standard?

What I'm wondering if it had plugs that were
later discontinued.

Thanks for any help,

GeneSF

To be honest, if somebody had mentioned BS317 with no particular context, I wouldn't have even recognized the number as an electrical standard.

I've just checked back in the oldest A.S.E.E. guide I have, but as that relates to the 13th edition of I.E.E. Regs. (1955), it has no mention of BS317 at all.

The standard 2/5/15-amp connectors in BS546 were all in use prior to 1950, so I would assume that all were also in BS317, but as for what might have been in BS317 but not BS546 I can only take an educated guess.

One candidate might be the 2-pin (non-grounding) version of the 15A plug and socket. These were quite common in pre-war properties, but were dropped in later years. I'm not sure the exact date they ceased to be made, but it could have been as late as 1950.

Thanks Paul,

The only reference to this standard when I entered it into Google, was at the BSA store where they mention that the BS546 standard replaced it.

Chronomedia's website mentions in their July
1947 entry that the BS1363 standard replaced seven round pin plugs.

http://www.terramedia.co.uk/Chronomedia/years/1947.htm

If you count the grounded and ungrounded versions of the common 2/5/15A plugs, that's 6. Must be a seventh discontinued one I never heard about.

Just curious.

Gene

It's quite possible that it didn't update the plug configuration, but rather improved the actual design of the body of the plug itself.

Older (pre WWII) UK plugs sometimes had screw on backs, didn't necessarily have proper cord grips etc.

The older sockets also had terminals which were very close to the surface of the wall plate itself and could potentially be contacted quite easily by children etc.

While many of the manufacturers, e.g. MK, had already adopted much higher standards, I suspect the official standard didn't necessarily specify them until BS546 was introduced.

I'd say somehow it was a 'tidy up' of the existing standard rather than one that actually radically changed the specification of the plug/socket system.

I'd say the only way of checking would be to find some historical technical archive as BS546 is around quite a long time now.

Similarly, the BS1363 standard has been updated in more recent years, not to change the overall plug configuration but to add things like the sleeved line/neutral pins (the plug shown on that 1947 page is a relatively new one).

I can't work out the seven connectors referred to there. If the 3-pin 15A was still specified, what was the odd extra one? If 3-pin 15A had already been dropped, then we're two short.

I actually have an multi-adaptor which includes a strange British plug. Ungrounded, two pin, small. I think I've seen this type of plug called a BS 3?? plug, where I have forgotten the two last digits... I do remember a Google search for this standard turned up blank. Could very well be BS 317.

Any chance of a picture?

You might be describing the 2-pin 2-amp connector -- Much smaller, shorter pins than the 5A version and set closer together.

It's the ungrounded travel adapter from Kopp AG in this PDF:

http://www.kopp-ag.de/de/pdf/adapter.pdf

5 mm pin dia, 16 mm long pins, 16 mm spacing.

Those measurements match up with the standard 2-pin 5-amp plug.

Here's one compared with the European equivalent, U.K. plug on the left:

That's the one. But is that part of BS 546? It has no earth pin...