"idiot proof" final circuit design

[:::Jerry::::]

have

Well, lets go back to bare wires and crock-clips, as even the present regulations causes such irritation to the majority, and if they wish to kill themselves then that's Darwinism...

[Dave Plowman (News)]

I doubt it. But have the sense not to try and run two 3 kW heaters off one extension lead, or to have extension leads that won't carry 13 amps.

You give the impression it's so common to be a serious problem. But if it was, I'd suggest changing to radial circuits would make things worse by having less sockets therefore more overloaded extension leads, etc.

I'm trying hard to remember the last plug fuse I had blow - despite having a vast number of electrical appliances. The one I do remember was on a 25" hybrid TV - it said 500 watts but would blow a 5 amp fuse.

What appliance have you had a fuse blow on recently?

[Andrew Gabriel]

Well, they don't do any harm either, and BS1362 fuses aren't only used in plugs.

[Adrian C]

Not with you on that one. The function of plug fuses was to protect the lead. An excess of fault current through a damaged and shorted thin cable normally used to carrying half an amp will cause heating and a fire risk. Internal fuses may be ineffective here.

-- Adrian C

[Doctor Drivel]

You are pathetic. The point is how to make a circuit idiot proof. We are not interested in your Little Middle England pro Tory and anti Blair crap.

[Andy Hall]

I thought Blair was a Tory.... Seems to have most of the characteristics.

[Dave Plowman (News)]

As has been pointed out, all flexes have to be capable of carrying somewhat more than 13 amps as a fault condition. But then if your flex is damaged, you shouldn't be using the appliance anyway until properly repaired.

But a fused plug is additional protection over and above what most of the rest of the world have.

[John Rumm]

Don't recall ever using vare wires and crock clips. Perhaps things are different in your neck of the woods.

You seem to be trying to solve a problem that for the most part does not exist. Much like Part P for example. Yes yuu can abuse fuses in plugs, but in the grand scheme of things it does not seem to be a regular cause of problems. People who abuse fuse ratings seem far more likely to abuse rewireable fuses in old consumer units in my experiance.

Like others have said, I don't recall having to replace a fuse in a plug for many years.

If you want to fix a problem, find a way to make sure that the earth terminals on IEC (cold) plugs don't splay and hence interrupt the earth connectivity to portable appliances. I have seen numerous power leads fail PAT testing for this.

[:::Jerry::::]

,

Well, nothing can stop that, even moulded plugs, and what's more if a moulded plug does need to cut off (for what ever reason) the plug is left with a lethal condition with bare wires exposed. IMO moulded on plugs should be outlawed, anyone who defends their design must be blind to their dangers.

without

So design it so that it's impossible to use the plug whilst the two halves are apart.

these

IMO those who can source such tools are not the people who are the problem, in general, although there are always the exceptions admittedly.

[Dave Plowman (News)]

Err, why would cutting off a moulded plug be a common thing to do by an idiot? Unless it's Drivel just wanting to find something else to use his hacksaw on.

Now if you were complaining about the dangers of badly fitted plugs in the days when they weren't moulded on I'd have to agree with you.

[:::Jerry::::]

,

amps.

need to

fuses.

It's more common that you seem to think though, taking the nation as a whole and not just personal experience.

worse by

How do you work that one out, radial circuits don't mean less outlets at all, it's true that it could mean more circuits though. Perhaps you are you more worried about cost than safety...

As for replacing fuses, it's the fact that they are still a user item designed to be replaced by everyone from expert to idiot rather than a fix unit that is reset (such as a MCB). If MCB's were fitted into plugs and the appliance came with the correct MCB-plug that would be one way to make the abuse of ring circuits that bit more difficult / common. This would also allow for backwards compatibility.

[:::Jerry::::]

those were

protect the

But as has been pointed out, being able to carry 13 amps is way under the possible maximum protection rating - something that you seem unwilling to understand, just because you haven't come across such a 'user instigated fault'.

But that's the point of the fuse, or do leads only get damaged when not in use?...

[Dave Plowman (News)]

Where's your evidence?

All radials tend to have a limit on the number of socket outlets per circuit. And judging by posts from those where such circuits are the norm, they're soon reached in practice. And your ideas on 'safety' seem to suggest that they would be protected in such a way as to also protect the appliance, which would mean something like 16 amp maximum. So easily exceeded by a couple of normal household appliances. In a normal household with reasonably well thought out rings, this really can't happen.

Are you serious? MCBs cost many pounds each. And do you think you could fit one into a plug without making it a stupid size?

I really think you're trying to find a solution for a problem that simply doesn't exist - or basing it on some dodgy workshop you've had the misfortune to work in. And I've seen many of those - but then rings aren't designed for this sort of use.

[Dave Plowman (News)]

[sigh] No it's not. Unless some cretin bypasses the fuse in the plug - and even a cretin knows the dangers of this.

Appliance leads very rarely get damaged. You're on about workshop use again. It's about time you improved your safety standards there.

[Nick Atty]

When I last shut this computer down, it did all the nice things, and then finished with a dramatic "phut!". It turned out to be the (5A) fuse in the plug. I replaced it, turned on at the mains and "phut!" again.

With a new PSU fitted it's working fine again. I'm pretty sure it could have taken a 13A out - it must have gone as close to short as makes no difference - but I'm happier it was a smaller fuse. No internal fuse involved.

So a perfect case of the plug fuse doing just what it should have done, and there being no internal one.

[:::Jerry::::]

,

plug and

sticks - or

Well, I bet a lot of dish-washers, dryers, washing machines and probably microwave ovens have there moulded on plugs removed when being connected to FCU's, even though you seem to think it's a pointless way of installing them....

You are becoming like 'Drivel', you are totally missing the point being made. :~(

[Dave Plowman (News)]

So you can't use a length of copper to replace the fuse in an FCU?

And yes, I do think it totally pointless. If you want a switch elsewhere from the socket - or a means of simply switching it off - use a 20 amp DP type. Neater, and the plug fuse still 'protects' the wiring, and you can simply unplug it when needed.

Sorry, Jerry, but your points are becoming increasingly difficult to follow.

[:::Jerry::::]

,

Yes, of course, but if the circuit is a radial that's also protected by a suitable MCB, in fact if it was a radial you would only need a CU and not a FCU.

elsewhere

No you can't, unless you have a plug and socket taking up space in a cupboard, and what if there isn't a cupboard near - what do you do when you have three appliances in a row, only the two end units are next to any possible cupboard.

The point was about bare cable being left sticking out of moulded plugs that have been cut off appliance leads (which is impossible to remove, unlike those that can be split), your comment about badly wired plugs was irrelevant.

[:::Jerry::::]

Your taking the p*ss aren't you, has your wife never run over the vacuum lead and damaged it, or worn the iron lead through on the ironing board etc., she must be one in a million....

[Doctor Drivel]

Then he should be your hero.