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I have ----ed a theory around in my head, that this sort of thing is kind of a side effect of good intentions / regulated de-skilling. Stay with me on this -

So even as recently when I was young, appliances came without plugs. As such I was eventually taught to wore a plug and along with this given a loose guide on which fuse to select from the tobacco tin in the shed and why.

However, in an effort to eliminate the dangers of poorly wired plugs, plugs now come moulded. This means fuses are only seen if one fails (which for many consumers and items is quite rare) rather than being introduced to the user to actually make an appliance work - each time they buy an appliance, from heaters to lamps.

So because fuses are interacted with less and less due to plugs arriving pre-fitted, it's understandable that as time goes on, your average public member won't have any reason to understand the fuse. But if you have to install it yourself - you should understand.

Now of course there's holes in my theory. I mean I've seen countless poorly wired plugs fitted in the 60's/70's/80's, or items from the same era with the incorrect fuse fitted - but I do feel that by having a consumer install their own plug, there is a need for the education and thus people perhaps have a slightly greater chance of having to understand basic consumer electrical theory.
 
People are not willing to learn. If they buy an item without a plug they will just call on the guy down the pub/ bloke down the road to fit it and we all know how good that guy is. Let's be fair, most people don't even take the cardboard off the plug that tells you what fuse is in it. If they could they would plug it in with the (useless) plastic prong cover still on. I think that supplying without a plug would be a step backwards.
 
Compared to wiring a plug there are far fewer and less dangerous things you can do with getting the wrong fuse. Worst case is a cable under-rated for a 13A fault clearance which is fire hazard in a range of high Zs cases when it fails the adiabatic limit.

Wiring a plug wrong allows a L/E swap. Why, Well brown is the colour of earth, isn't it?

To me what is more dengerous these days is the crap off eBay and the likes. Recently a friend of mine got various tablet computers and they came with (I think) USA adaptors and a unfused 13A converter for them. It even had under-sized pins. I told her to bin the adaptors and contact trading standards, but I doubt anything happened.
 
In my eyes the problem shouldn't even exist anymore.

I don't feel its down to the customer to be clued up on how to change the fuse, I know nothing about Chlorine Trifluoride which to me is equally as dangerous.
But i can't just go and buy that off the shelf.

The fuse sizing mentioned here is a good idea and the only work around possibly.
Moulded plugs have stopped most people dabbling around with taking them off and putting them on to something else, though that has nowhere near eliminated the problem. It's almost like the moulded plugs should have a mini mcb built into it but perhaps that technology isn't here yet to make a switch/button so small.

To me it just seems like a really massive problem in a world of Electrics where we have some amazing safety devices and protective regulations.

My sister rang yesterday and said had I got any 13amp fuses, I asked her what it was for, she replied, 'my hairdyer' lol
 
Is it true , most appliance cables now 0.75mm ?
Reason for 15A .. Fuse busting capability.
..Thanks to fuse less European plugs ...
(Dumbed down like somewhere else )
 
a bit unrelated, but.... my lady's Ford (2012 vintage) has a BS1361 socket in back of centre console, so ther must be an inverter somewhere. it wasn't working. investigation found that the inverter was fed , along with the cig'lighter from a 10A fuse, which had blown. 10A@12V eaquates to 0.5A @ 240V. bloody pointless when the female of the species plugs in hair dryer/straighteners etc. it would even struggle to charge a mobile phone. what's the point?
 
some numpty takes out a 3A fuse and replaces with a 13A. BOOM ...... Darwinism strikes again.
Probably of an old laptop , they had the power mobile phones have now ! ( Fancy accesories -were Silly money )
... or other low current purposes ..The mind would boggle... ouch ...
 
I think there is somewhat of a confusing idea of plug top fuse rating here, for the majority of plug tops the fuse is simply there for short circuit protection and not overload as the majority of appliances would sit in the category of fixed load device/item.

If you actually look at old vacuum cleaners (bigger motors) or fridges etc you will note that the fuse (13amp) is larger than the rated current carrying capacity of the flex so for all purposes it cannot be there for overload protection as the flex would readily melt and short before the fuse popped, inrush on both these items limit the choice of fuse fitted to 10amp and 13amp but as we no longer recognise 10amps our PAT testing values then we see 13A been the fitted fuse of choice.

Noted here that this does not apply to extension with multiple outlets as this by its nature does need to overload protect the cable as it does not fit in the fixed load category even if items plugged in do, noted it is easy to plug in various heavy loads and exceed the flex rating so fusing needs to be correct.

Smaller fuse ratings are commonly put on electronic goods with low inrush and low current demands, it can be argued that it helps protect the electronics in the event of a S/C by reacting quicker but in truth a dead short will not be all too fussy at blowing a 13amp or a 3amp instantaneously and if a device has sensitive electronics then by good design it should have a quick acting fuse integral to the electronics.

The only risk of fire I see is if the load is not fixed which is rare in normal domestic items although those that carry say motors etc will have integral thermal protection anyway by design, a stalled motor should be protected in other ways than a plug top fuse.
 
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Returning to the original point, these days almost all appliances are fine with a 13A fuse. They are designed to withstand being protected at 16A for EU-wide compatibility, which as mentioned has driven the general use of 0.75mm² flex. The only plugs that definitely require a smaller fuse are extension leads rated <13A (which are a menace anyway) and old appliances and lights with 0.5mm² flex or where the manufacturer stipulated that fuse size. FCUs might require a fuse <13A for some dopey extractor fan or to achieve disconnection times where deriving a long radial circuit with high Zs, but this is a limited application and typically again a 13A fuse would probably offer sufficient protection.

We have to look at the plug fuse in context today. Applilances are built with more internal protection against overload and faults, so a plug fuse <13A is no longer a key component in appliance safety. Its other purpose, to allow appliances to be used on highly rated circuits (32A) is still a boon, but that doesn't require any fuse other than 13A. I say it is a boon because it allows us to do more with less, because the additional diversity of one 32A circuit over two 16A circuits often allows it to do the work of three or four 16A circuits without nuisance tripping. But it would be impractical to fit flexes suitable for fault protection by a B32, so the fuse pays its way.

E2A crossed with DW, very similar ideas there.
 
It's almost like the moulded plugs should have a mini mcb built into it but perhaps that technology isn't here yet

I proposed a different solution in the mid 1980s, around the time IEC 60906-1 16A plugs were on the table as a possible global standard. My approach was to build the MCB into the socket, so that 16A sockets with unfused plugs could still be used on 32A circuits. The idea was that the plugs would be smaller, neater, cheaper and less prone to overheating (a disadvantage of a fused plug). The MCB would simply replace the switch in the socket. It could be mechanically interlocked with the plug so that it would only operate with the plug pushed fully home, and would trip if the plug was pulled out.

To retain the benefit of being able to fuse down below 16A, I also saw the possibility of two different profiles of plug that either engaged or missed a lever in the socket that would alter the MCB calibration. E.g. moulded plugs to be protected at 5A would miss the lever, 16A versions would depress it, and rewireable plugs would have a tab that could be folded to one side or the other according to application. That could then be interlocked with the flex clamp so that fitting an oval or small diameter flex would cause the clamp to press on the edge of the tab and prevent it being flipped over to the 16A side.

But IEC 60906 and my ideas were all ahead of the times. Brazil and SA have since adopted the plug, and the MCB-socket is available from Bticino in Italy.
 
I remember having a couple of multi plugs in the 70's. They were adaptable to 13 amp, 5amp round pin and 15amp round pin, fitted to leads so you could pick up what supply was available. Thinking about it, I can't remember if they were fused or not......anyone remember them?
I'm sure I'll still have one, stuck away somewhere....determined to find that now.
 
That was the Fitall. It had to be fused at 13A because of the 13A pins (there has never been an unfused 13A variant.)
JW has a page:
 
'nuff said.
That was the Fitall. It had to be fused at 13A because of the 13A pins (there has never been an unfused 13A variant.)
JW has a page:
That looks like the one, with the slider at the bottom. Really handy. That long since, I couldn't remember the fuse.

Get this class for a body shop welder.....'nuff said.
 

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Looks OK to me, I think it's one of these:
3/5/13 Amp Fuses For Plugs And Fused Spurs... D1 fuse - EletriciansForums.net
 

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