Ring extension load

[PBC_1966]

I have to agree with John that diversity on feeders is not the same thing at all, since the feeder is still adequately protected at source so that a fuse will blow if somebody does switch every single thing on at once and overload the circuit. That's not going to happen with a double 13A socket unless it's on a 20A radial circuit.

I would also question this:

Remember that in the 40s and 50s any load over 1 kW was quite unusual in a domestic situation.

There were plenty of two-bar (and for that matter three-bar) electric fires in use then, more so than today given that central heating was still comparatively rare in British homes at that time. And how about the ubiquitous electric kettle, normally at least 2kW? (Although to be fair, most were probably connected to the single socket incorporated into the cooker control unit.)

Twin tub washing machines with integral heaters became more popular too. While the chances of a washer and dryer being connected to the same double socket have, I would say, increased immensely in more recent times, I think it would be fair to say that outside of the kitchen & utility areas the loads on 13A sockets around most of the house have, on average, probably decreased.

 

[AndyPRK]

thanks for the experiment fred.

Some photo's of the setup would have been nice to fully understand what is getting hot

 

[Echo the husky]

I will take some photos. My real name is Matt btw! I don't know why I used freddo when I signed up here all those years ago. I'm also known as Echo who is that fluffy dude in my avi.

 

[Echo the husky]

OK here are some photos I tried to match them to the thermal pics.

The loads.

The 2 Plugs at the end of the test, shown with their lids removed.

Rear of socket.

Top rear of socket.

20A through 13A fuse. The flex was draped around the socket to keep it from melting the carpet!

 

[PBC_1966]

Who cares about overheating fuses, plugs and sockets, undersized cables for the protective device and all that trivial stuff? I just hope you have an RCD on that lot!

 

[Echo the husky]

I just hope you have an RCD on that lot!

You're not going to go on and on about that are you?

I'd better make the ring a ring again too.

 

[PBC_1966]

You're not going to go on and on about that are you?

No need - I'm sure someone else will be along shortly to tell you that your experiment was illegal.

 

[DaveHerns]

Maybe he's made a New Year Resolution not to go on and on (and on)?

 

[ban-all-sheds]

Why don't you prove your assertion with reference to BS1363.

Err - how about for the blindingly, obviously, simple reason that for me to prove the standard does not contain something I would have to post the whole thing in its entirety and invite everybody to read the whole thing and to note that they cannot find what you claim is there.

Whereas for you to prove that it does contain something your quoting of the relevant part(s) would be very trivial.

Hopefully everybody else here is as offended as I am that you think we are all so stupid as to think that you have a point and that I should do what you suggest.

It really is so simple that I'm sure even you can understand it:

the Standard requires 20A rating and they must not be used to supply more than this.

Please show us where the standard says that.

Or fail to do so and accept that you are wrong.

 

[JohnW2]

Goodness. It's New Year's Day FGS ... don't you ever "loosen up"?

Kind Regards, John

 

[ban-all-sheds]

From what I understand of modern connector theory (e.g. 5A through a tiny USB C-Type connector) there is no reason that those massive 13A plug pins couldn't have coped with the current, but maybe metallurgy science at the time was not up to the job.

Logically, if they had thought that a double socket could cope with 26A they would have made that the standard. I guess we will never find out which manufacturer was most involved with the standard development. But they have a lot to answer for.

Logically they would not have used rectangular pins at all - round ones going into a sprung sleeve would have provided a much greater contact area. Obviously they would have had to change the layout, but sticking with the fundamental design of the 15A BS546 would have been better.

 

[Echo the husky]

Goodness. It's New Year's Day FGS ... don't you ever "loosen up"?

Do that to his terminals and he'll start overheating.

 

[Echo the husky]

...but sticking with the fundamental design of the 15A BS546 would have been better.

On 2 occasions now I have wired radial circuits feeding a 15A 546 socket for a single heavy load. Both were for 3kW heaters in lounges where the sockets and plugs would overheat around the line pin and fuse etc. when they were used for extended periods. With the 15A socket there was no sign of any heating.

 

[JohnW2]

Goodness. It's New Year's Day FGS ... don't you ever "loosen up"?

I look forward to seeing a rational explanation from you of why the date should make any difference to how I view that ridiculous suggestion from Risteard.

I might even frame that one!

Kind Regards, John

 

[Risteard]

Err - how about for the blindingly, obviously, simple reason that for me to prove the standard does not contain something I would have to post the whole thing in its entirety and invite everybody to read the whole thing and to note that they cannot find what you claim is there.

Or you could just post the bit which states about a double socket-outlet requiring a rating of 20A, and demonstrate that this states that it is to be greater than or equal to 20A and not equal to 20A.

Of course without knowing the BS1363 Standard verbatim you might have the known knowns and the known unknowns, but then there are the unknown unknowns as well.

Sound familiar?