Everything has to be 13 Amp??!!

[SimonH2]

Personally, I think the examples above where the advice is wrong should result in a written complaint to the department involved, asking them to explain why they are offering incorrect, or even dangerous, advice. Ask for a copy of their risk assessment criteria, and how they arrived at their advice.

Do it in writing so that they cannot "forget" it happened or dispute the contents as can happen with phone calls. Insist on a written reply so they can't dispute what they said. If you don't get a satisfactory response, then take it higher until you do.

As said, many people making these rules really have no idea what they are doing. That will only change when someone who does know what they are doing is prepared to challenge them.

As if the Fire Service wanted to confiscate an adapter like that, I'd just tell them that they can take it if they don't mind me reporting it as aggravated robbery to the Police. Making sure you get their details and writing them down also tends to concentrate the mind (for any official) as they then can't say "it wasn't me, must have been someone else".

 

[EFLImpudence]

I am surprised at this:

http://www.esc.org.uk/public/home-electrics/plug-fuses/

Which I discovered while planning my scout assignment the other week.

So, that means flexes under 1.25mm2 can have 13A fuses?

Yes, actually. I recall a reg which allows a 13A fuse for cable above 0.75mm² as long as it's <2m in length. Check out any IEC C13 cable supplied with a PC, PSU, monitor..

But don't quote me on it. I don't have access to a copy of BS7671 (my library subscription does not include it, which is beyond annoying).

E: Actually, it's in BS1363-1, Table 2. 13A fuse for all conductor sizes above 0.5mm², and the 2m rule is for 0.75mm² being rated at 10A:

The figure in brackets indicates the flexible cord size which may be used for cord sets where non-rewirable plugs are used with a maximum flexible cord length of 2 m.

So, there you have it: 13A is deemed sufficient for protection of flexible lead sets above 0.5mm².

That may be so but the link is still incorrect by referring to wattages and not mentioning the flex/cable.

There are lots of appliances over 700W which should not be on a plug with a 13A fuse.

 

[Monkeh]

I am surprised at this:

http://www.esc.org.uk/public/home-electrics/plug-fuses/

Which I discovered while planning my scout assignment the other week.

So, that means flexes under 1.25mm2 can have 13A fuses?

Yes, actually. I recall a reg which allows a 13A fuse for cable above 0.75mm² as long as it's <2m in length. Check out any IEC C13 cable supplied with a PC, PSU, monitor..

But don't quote me on it. I don't have access to a copy of BS7671 (my library subscription does not include it, which is beyond annoying).

E: Actually, it's in BS1363-1, Table 2. 13A fuse for all conductor sizes above 0.5mm², and the 2m rule is for 0.75mm² being rated at 10A:

The figure in brackets indicates the flexible cord size which may be used for cord sets where non-rewirable plugs are used with a maximum flexible cord length of 2 m.

So, there you have it: 13A is deemed sufficient for protection of flexible lead sets above 0.5mm².

That may be so but the link is still incorrect by referring to wattages and not mentioning the flex/cable.

There are lots of appliances over 700W which should not be on a plug with a 13A fuse.

The fuse in the plug is not to protect the appliance. It is to protect the cable.

 

[EFLImpudence]

The fuse in the plug is not to protect the appliance. It is to protect the cable.

Precisely. As I said -

That may be so but the link is still incorrect by referring to wattages and not mentioning the flex/cable.

 

[Monkeh]

The fuse in the plug is not to protect the appliance. It is to protect the cable.

Precisely. As I said -

That may be so but the link is still incorrect by referring to wattages and not mentioning the flex/cable.

You also said:

There are lots of appliances over 700W which should not be on a plug with a 13A fuse.

Which has no relevance: The fuse is to protect the cable, not the appliance.

I have no interest in the link anyway, I was simply making clear that yes, smaller flex sizes can have 13A fuses.

 

[SimonH2]

There are lots of appliances over 700W which should not be on a plug with a 13A fuse.

Which has no relevance: The fuse is to protect the cable, not the appliance.

Sorry, but I can't see what your problem with that statement is - other than too literal an interpretation and deliberately ignoring the context.

If the appliance is over 700W then a 3A fuse isn't suitable. Thus the argument goes that you need to use a 13A fuse - intermediate sizes having been deprecated.

You are correct that it is the flex that matters, but unless it's a detachable flex, then the flex is part of the appliance and so it is correct (but arguably incomplete*) to say that some appliances** over 700W aren't suitable for a 13A fuse.
* The full statement would be "the appliance isn't suitable for a 13A fuse ... because the integral flex is too low a current rating".
** Where "appliance" means the actual device and it's integral cordset.

 

[securespark]

I find it odd that the advice from the ESC is that appliances over 700W should be fitted with a 13A fuse. That's OK if the flex is suitably rated, but usually appliance manufacturers fit sub-13A appliances with a flex of CSA relating to output of the appliance.

Therefore, you would end up with many appliances fitted with a 13A fuse that have a cord CSA < 1.25mm2.

Obviously, this seems at odds with BGB:

0.5mm2 = 3A
0.75mm2 = 6A
1mm2 = 10A
1.25mm2 = 13A.

The only other time this rule is broken is when you find 0.5mm2 flex feeding lampholders protected by a 5, 6 or 10A device.

 

[ban-all-sheds]

Don't forget that the fuse only has to provide fault protection, not overload.

 

[securespark]

Sure.

Might as well do away with the 1362 fuse and rely on the CPD for fault protection....

 

[ban-all-sheds]

Hey - it's not my idea.

But maybe you could - how do the I²t figures compare? Particularly vs a B20 or 25?

 

[EFLImpudence]

The fuse in the plug is not to protect the appliance. It is to protect the cable.

Precisely. As I said -

That may be so but the link is still incorrect by referring to wattages and not mentioning the flex/cable.

You also said:

There are lots of appliances over 700W which should not be on a plug with a 13A fuse.

Which has no relevance: The fuse is to protect the cable, not the appliance.

I have no interest in the link anyway, I was simply making clear that yes, smaller flex sizes can have 13A fuses.

You may have no interest in the link but it is the link about which I was commenting.

It says appliances under 700W should have a 3A fuse and appliances over 700W a 13A fuse.

NO mention is made of any cable which you rightly say the fuse is to protect.

My irrelevant reference to appliances over 700W was, for example, ovens, hobs, showers which according to the link, read by Joe Public, should be on a plug with 13A fuse.

 

[ban-all-sheds]

As if the Fire Service wanted to confiscate an adapter like that, I'd just tell them that they can take it if they don't mind me reporting it as aggravated robbery to the Police. Making sure you get their details and writing them down also tends to concentrate the mind (for any official) as they then can't say "it wasn't me, must have been someone else".

I'm sure it would be just as effective to just say "No".

AIUI the person concerned didn't protest.

 

[Monkeh]

The fuse in the plug is not to protect the appliance. It is to protect the cable.

Precisely. As I said -

That may be so but the link is still incorrect by referring to wattages and not mentioning the flex/cable.

You also said:

There are lots of appliances over 700W which should not be on a plug with a 13A fuse.

Which has no relevance: The fuse is to protect the cable, not the appliance.

I have no interest in the link anyway, I was simply making clear that yes, smaller flex sizes can have 13A fuses.

You may have no interest in the link but it is the link about which I was commenting.

It says appliances under 700W should have a 3A fuse and appliances over 700W a 13A fuse.

NO mention is made of any cable which you rightly say the fuse is to protect.

My irrelevant reference to appliances over 700W was, for example, ovens, hobs, showers which according to the link, read by Joe Public, should be on a plug with 13A fuse.

I apologise for missing that rather odd point. I'm not good at thinking like Joe (middle name Moron) Public.

 

[StuDH]

Refering to my original post; the fire safety officer arrived today for the inspection.
He was quite reasonable! He said that they 'didn't like' 3 way mains adaptors', but approved 4 gang extension leads. We had 2 adaptors, but he never tried to ban them or say anything silly about them. Instead, he left 2 ( free ), 4 gang extension leads for us to use.
He also decided that our 2 present smoke alarms didn't cover enough downstairs, so he supplied and fitted another one in the hall - again quite free !
We also had to sign a disclaimer that basically said his role was advisory and he couldn't be held responsible in any way; this was quite satisfactory as he also said not to hesitate for more advice at any time in the future. Quite a decent chap and very helpful!!

 

[EFLImpudence]

I apologise for missing that rather odd point. I'm not good at thinking like Joe (middle name Moron) Public.

You don't want to be 'normal' these days.