Wiring remote switched sockets for Kitchen appliances

[JohnW2]

Given what has been said about suitability for foreign markets and 16A OPDs, I'm struggling to follow that logic to a point where any fuse other than 13A is required.

As I said, it depends whether "we" regard the practices of other European countries to be adequately 'safe' in the mind of the UK.

I would imagine that if you looked at some "very foreign markets", you would find some electrical practices which would definitely not be regarded as acceptable in the UK!

In the meantime, I'll continue to choose fuses based on the power of the connected appliance.

Same here. As I often say, that is 'how I woz brought up', coupled with 'why not?'. As I also often say, for this reason I must be one of the best customers of suppliers of 1A BS1362 fuses

Kind Regards, John

 

[oldbutnotdead]

That 3A/13A fuse one is odd. PAT exam there was one question (think it was something like what fuse should go in the plug of a 240v 800w resistive load appliance) where the instructor told us that in the real world you'd use a 5A fuse but in the exam you had to use a 13A fuse (since 3A would not be adequate).

 

[EFLImpudence]

Given what has been said about suitability for foreign markets and 16A OPDs, I'm struggling to follow that logic to a point where any fuse other than 13A is required.

Exactly.
On a 32A circuit, depending on the nature of the load, the 13A fuse may not actually be required either.

In the meantime, I'll continue to choose fuses based on the power of the connected appliance.

You are, of course, free to do so.

What fuse would you use for a 60W (or 5A led) inspection lamp?

 

[EFLImpudence]

That 3A/13A fuse one is odd. PAT exam there was one question (think it was something like what fuse should go in the plug of a 240v 800w resistive load appliance) where the instructor told us that in the real world you'd use a 5A fuse but in the exam you had to use a 13A fuse (since 3A would not be adequate).

As above, with a resistive load which cannot overload the flex, no fuse would actually be needed but you have to fit something in the British plug.

 

[JohnW2]

What fuse would you use for a 60W (or 5A led) inspection lamp?

As you know, in my case, the answer would (on the basis of "why not?") be 'the smallest available', which would be 1A. I agree with you that such a load does not require any fuse at all (so a 13A one would be just as adequate) but we don't have that option - as you have also said, with a BS 1363 plug one has no choice but to put some fuse in it.

Kind Regards, John

 

[echoes]

Exactly.
On a 32A circuit, depending on the nature of the load, the 13A fuse may not actually be required either.


You are, of course, free to do so.

What fuse would you use for a 60W (or 5A led) inspection lamp?

If it has 'normal' plug then I'd use a 3A fuse. @JohnW2 would use a 1A, but I don't have any(!). But I do understand that a 13A fuse may be permissible, it just seems sloppy.
On the other hand, if the flex was large enough, and had one of these on it:

then it wouldn't be individually fused, nor need to be!
An advantage of using the smallest suitable fuse is to maximise discrimination - we all seem to have stories about 13A fuses surviving when a 32A MCB has tripped. No so much with 3A fuses.

Perhaps I suffer from an up-bringing where a plug containing an unnecessary 13A fuse was frowned upon

 

[echoes]

As above, with a resistive load which cannot overload the flex, no fuse would actually be needed but you have to fit something in the British plug.

I'm with you.
So wedging a screw in the fuse holder might be wrong, but not for the reasons which might spring instinctively to mind.

 

[JohnW2]

Perhaps I suffer from an up-bringing where a plug containing an unnecessary 13A fuse was frowned upon

It sounds as if you "woz brought up" in the same way as myself

Kind Regards, John

 

[echoes]

It sounds as if you "woz brought up" in the same way as myself

Kind Regards, John

That's right! And if the opportunity arises for discrimination (of the current/fuse variety), why miss it?

 

[JohnW2]

I'm with you. ... So wedging a screw in the fuse holder might be wrong, but not for the reasons which might spring instinctively to mind.

I once came across a plug which had clearly be wired by someone with such an approach. They had clearly removed the neutral pin (with it's terminal) from another plug and used it to replace the L pin in the one in question, discarding the normal L terminal (with associated fuse clip). He/she had thereby created what appeared to be a BS 1363 plug, but without even any provision for a fuse!

Kind Regards, John

 

[JohnW2]

That's right! And if the opportunity arises for discrimination (of the current/fuse variety), why miss it?

Quite ... that's my "Why not?" argument (coupled with the possibility that there is an outside chance that it just might one day limit the damage in some connected equipment that had inadequate/sub-optimal internal protection).

Kind Regards, John

 

[echoes]

Quite ... that's my "Why not?" argument (coupled with the possibility that there is an outside chance that it just might one day limit the damage in some connected equipment that had inadequate/sub-optimal internal protection).

Kind Regards, John

Indeed - if my plinth heater motor became stalled, there's a chance of a 3A fuse in its FCU blowing before the blue smoke escaped.

 

[mwatsonxx]

I wonder how many people could get killed reading this nonsense and thinking it is correct advice

 

[EFLImpudence]

Quite ... that's my "Why not?" argument (coupled with the possibility that there is an outside chance that it just might one day limit the damage in some connected equipment that had inadequate/sub-optimal internal protection).

I can understand your thinking in a way but when explaining regulations and electrical principles, it is not logical to do so at length and then say "but I would still do something else because I just feel better".
Also, you frequently state quite correctly that fuses etc. do not limit the magnitude of a fault current but merely the duration so a few milliseconds, if any, are all that is involved.


Is this a good analogy?
You fitted an extractor fan which called for a 3A fuse so, obviously, you fitted an FCU with one. Then when needing a new fan the manufacturer of this one knew what he was doing and did not call for a fuse.
Would you remove the FCU? Of course not, but is it doing any good?
Would you fit a 5A or 13A fuse? Probably not, but it doesn't matter, does it?

 

[EFLImpudence]

Indeed - if my plinth heater motor became stalled, there's a chance of a 3A fuse in its FCU blowing before the blue smoke escaped.

I think John once worked out that an extractor fan stalling could not cause enough overload to blow a 3A fuse.

I expect he we remind us.