I recognize those 15A outlets very well, as when I was a kid in the early 1970s you could still see plenty in service in places such as village and church halls.
They're typical 1940s style, although as this was back in the days when designs weren't altered every five minutes it's a little hard to be more precise. They mey have made these into the early 1950s, but these look as though they don't have shutters.
Shortly after the introduction of the BS1363 shuttered socket (late 1940s), manufacturers tended to add shutters to their BS546 versions as well.
By the way, the switches on these are the quick-make-&-break type making them suitable for both AC and DC use.
[This message has been edited by pauluk (edited 03-12-2005).]
Re: BS546 plugs & outlets#142862 03/13/0503:10 AM03/13/0503:10 AM
Oddly enough, We did get a variation on the round pin theme here in NZ. It was called the 5A Clock plug. I'm still searching for a decent picture of one and I think that HPM still has a plug/socket arrangement like this. The socket was recessed into the wall (to fit behind a clock) and the plug fitted into the recessed socket. They were 3-pin, but most clocks of the era were only fed with 2-core Tru-rip.
You can still buy the dedicated "clock connector" here, which has been around for many years:
The front plug section has three very small flat blades which fit the outlet, and contains a cartridge fuse to BS646. They're ceramic-bodied fuses similar to the BS1362 fuse which is found in the 13A plug, but considerably smaller and available only in sizes from 1 through 5 amps.