You do realise, don't you, that whatever he tells you, it is not applicable to any products except the ones which that manufacturer manufactures?Friday afternoon I spoke to an ex-colleague who deals with product compliance issues for a major manufacturer of wiring accessories.
At no time have I said that there are no twin sockets made which can't "handle" (however you want to define that) 26A.
I'm quite prepared to accept that there are manufacturers who make twin sockets which can handle a 26A load indefinitely, without overheating.
But that does not make that a generic capability. If a conformant socket does not have to be able to do that in order to conform, then you cannot have any degree of certainty that one will. (Apart from one from Brand X Electrical Accessories Ltd if they say that theirs do.)
Indeed.When I asked him how much current could safely be drawn from a twin socket-outlet his response was "For how long?".
Let's call the 14+6A the lower bound.
And let's call 1,000,000 amps the upper bound.
We know that at the lower bound for several hours the socket has to not overheat, and to not still be heating up. Probably fair to say that at that lower bound it could cope indefinitely.
I think that without any testing we could all form a reasonable opinion that at the upper bound the socket would exhibit extreme thermal distress within a very short time.
So - somewhere between the lower bound and the upper bound a twin socket is not going to be able to "cope" with the current.
But at what point? We don't know, because to conform to BS 1363 a twin socket does not have to demonstrate any ability to cope with any load for any length of time apart from 14A+6A.
Would that point be 26A for 10 minutes? We don't know, because to conform to BS 1363 a twin socket does not have to demonstrate any ability to cope with any load for any length of time apart from 14A+6A.
Would that point be 26A for 4-8 hours? We don't know, because to conform to BS 1363 a twin socket does not have to demonstrate any ability to cope with any load for any length of time apart from 14A+6A for 4-8 hours.
Would that point be 26A for 1 hour? We don't know, because to conform to BS 1363 a twin socket does not have to demonstrate any ability to cope with any load for any length of time apart from 14A+6A for 4-8 hours.
Does the ability to cope with 14A+6A for 4-8 hours mean that it must be able to cope with any load beyond that? Clearly not.
Does the ability to cope with 14A+6A for 4-8 hours mean that it must be able to cope with 13A+13A? We don't know, because to conform to BS 1363 a twin socket does not have to demonstrate any ability to cope with any load for any length of time apart from 14A+6A for 4-8 hours.
Can you not see? WE DON'T KNOW.
Why that long? Is 30 minutes the duration associated with the "normal use" provision(s) in BS 1363? I thought we didn't know.I suggested 30 minutes,
I'm not sure why that would be relevant.when his next question was "Is it on a ring?".
But if it is, then that is one more factor which we don't know about when saying what a socket can handle, as we don't know whether a socket will necessarily be on a ring or on a radial. If it is relevant then that is one more reason why we don't know how one would perform when loaded more onerously than the standard requires one to tolerate.
It would also be the case for some sockets on a radial.I suggested that we consider one with an incoming and an outgoing cable, as would be the case on a ring final,
Oh - and BTW, from the POV of a socket on a ring, both the cables are incoming.
Which it does, although until now I'd never looked.and unlike the heat rise test in BS1363 which only uses an incoming cable.
As it does, I do have a couple of questions about that.
- Both I and Herr Dr. Kirchoff would be fascinated to know how one could arrange for an extra 6A to flow through the cable if it served only the socket drawing 14A.
- And I would love to understand the scientific/engineering principles behind it being relevant to how hot a socket gets when current is drawn from it.
But be that as it may, if it is relevant then I'm afraid that whatever argument you think you have made in support of your assertion that a twin socket must be able to cope with 26A has just crumbled to dust and blown away, because any socket might be the last one on a radial and therefore not have the significant outgoing cable.
Shall I add "please show me where BS 1363 specifies different ratings/performance/behaviour/whatever-you-want-to-call-it for sockets on rings, radials and the ends of radials" to the list of things you can't find in BS 1363?
And is he equally confident that every single make of twin socket in the world which legitimately conforms with BS 1363 could comfortably carry 13A through each outlet under those circumstances?He was confident that a good make of twin socket could comfortably carry 13A through each outlet under those circumstances.
Or is it a case that when considering the capabilities of every single make of socket in the world, "we don't know"?
And even with his sockets, what about different circuit topologies? That variable is not considered by the standard. So if it is relevant, then what happens when sockets are not wired according to the circumstances you specified to him? Could it perhaps be "we don't know"?
I have no reason to have even a shred of doubt that that is true.He told me that their in-house sample tests are performed at 15A on each outlet (exceeding the BS1363 test),
But so what? Other makers may not do that test because they are not required to.
Can you really not see?
All we know is that a conforming twin socket has to be able to handle 14A + 6A without overheating. The standard does not require any demonstration of any characteristics at any loading outside of that for any length of time.
Can you really not see? We don't know.
Unless they have tested every single make and model of socket available, and unless they have procedures in place to ensure that they always test all new ones, and unless they have the power to force the withdrawal from sale of any sockets which cannot perform in a way which BS 1363 does not require them to behave, whatever they tell you is irrelevant.I now have some contact details for a couple of independent test labs, so I'll see what they have to say on the subject next week.
Because unless they can say "yes" to all of those provisos we don't know how a socket will perform outside of the environment mandated by BS 1363.
Can you really not see?
WE
JUST
DON'T
KNOW.