American electrics

How many people would run a 3kW fire from an extension? But in any case, the extension will be clearly marked with its maximum load. If an idiot doesn't understand that then perhaps Darwin should apply?

No it's not if the guidelines are followed. If it were 'open to abuse' it would have been superseded.

Reply to
Dave Plowman (News)
Loading thread data ...

Probably less than you'd think, since they'll act as electrode heaters as well as element heaters.

For a bit... the fuse should pop when the waters reached about the right temp. Your MTBF might be on the low side though. As might your family's MTTD.

NT

Reply to
bigcat

,

they

Perhaps, but then things are meant to be made safer, if Darwinism is the way to go - bare wires straight off the meter and crock-clips around the house....

abuse' it

There is nothing to stop any idiot, who can open a plug, replacing a

3amp fuse with the shank of a 8mm bolt, with radial circuits and final protection back at the distribution board that is not so easy, especially if that final protection is via circuit breakers - so yes, the final 'ring circuit' is wide open to abuse. It was years before all appliances came pre-fitted with plugs and the correct fuse, how many people fitted a plug without then changing the supplied 13amp fuse to the correct lower rating?...

As I said, the final ring circuit is a 'one size fits all' solution that is open to abuse.

Reply to
:::Jerry::::

And when there were different sizes of plugs, what was to stop an idiot using a five amp one for a 3 kW heater?

Reply to
Dave Plowman (News)

,

replacing a

before

13amp

solution

True, but then the final protection would trip...

Reply to
:::Jerry::::

Decades ago we had exactly that system. All sockets were on radials, all fused at the fuseboard. There were 3 ratings, 2A, 5A and 15A, ensuring each apliance was ideally fused. Each appliance had the right plug fitted, and there was no plug fuse to tamper with.

There are a veritable list of good reasons why we moved away from that system to what we now have. It was riddled with problems inherent in its design, as well as the more well known problems in its implementation.

The whole point of having fused plugs is that a faulty appliance that pops a fuse is disconnected, so if its plugged in again, to another socket, it isnt live once more, and dangerous once more.

The whole point of having appliance fuses in plugs rather than at the fuseboard is so that it is practically possible to fit the right fuse. It doesnt guarantee it by any means, but it means the right fuse will frequently be used. When the fuse is at the board, the applince will simply use whatever fuse supplise that socket, regardless.

The whole point of having both a plug fuse AND a fuseboard fuse or mcb is that if one is defeated, there is a backup still working.

The whole point of rings instead of radials is to increase safety, reliability and socket availability.

EVERY system is open to abuse. Our ring system puts safety backups in place in case of abuse. Your all-radial vision does not.

And your radial system leaves dangerously faulty appliances in a dangerous state. And the risk of fixed wiring fire is significantly higher, and so on.

Does anyone understand the ring system these days?

NT

Reply to
bigcat

You weren't around in the days of those radial circuits? It was common to see both 5 and 15 amp plugs on the same circuit.

Reply to
Dave Plowman (News)

And nails in the fuse box

Reply to
EricP

,

common to

I was actualy...

But that is not what you originally implied, someone trying to run a

3kw heater off a 5amp supply. What is the difference between someone running a 5amp load off a 15amp radial circuit and someone leaving a 13amp fuse in a BS 1363 type plug, or worse still, using that bolt to bridge out were the fuse goes and thus protecting something at 30amp rather than the correct 5amp ?...
Reply to
:::Jerry::::

replacing a

before

13amp

solution

radials,

will

solution

Only if abused by idiots, as is any system.

Only if someone is daft enough not to recognise that the appliance is faulty, or are you saying that the final protection is somehow different on a radial circuit?

Any way, if someone puts another fuse into a BS1363 type plug, the appliance is again dangerously faulty, and will again trip it's protection device. You seem to be making an argument for totally fix wiring, with all appliances connected via FCU's !...

As for fire risk, how is it any higher on a correctly protected radial circuit than a correctly protected ring circuit - if you are correct why do we still use radial circuits in houses even today ?!

I suspect more than you think, and many can see the problems with it.

Reply to
:::Jerry::::

,

A bit like now, what with people bridging the fuse space of BS1363 plugs with nails or bolts and replacing fuse wire with large cross section wire that would still be good for many hundreds of amps.....

No system is going to prevent blatant abuse, the problem with the BS1363 type plug and 30amp ring circuit is that it's far to easy for someone to fit an incorrectly rated fuse and not even be ware that they have done anything wrong.

Reply to
:::Jerry::::

And irons plugged into ceiling lights.

Reply to
John Cartmell

,

Apart from education, the non supply of bayonet plugs and the correctly rated protection of those circuits, what is there to stop some idiot doing that today ?

Reply to
:::Jerry::::

No - I said using a 5 amp plug. Didn't say anything about the supply, which were usually a 15 amp radial.

The fuse in the plug top is to protect the appliance - not the circuit. If you overload the appliance - or in this case extension lead - it will be obvious by the smoke. Overloading a circuit with concealed cables is a different matter

Reply to
Dave Plowman (News)

Given they are different colours I'd say it's impossible to do without knowing.

Reply to
Dave Plowman (News)

What happens instead is, "Oh, I wonder which appliance blew the fuse?" Start trying them all in another circuit, and eventually BANG!. "Oh it must be this one". That's the best result in this circumstance

-- you only blew the circuit protection twice and generated two small explosions in some appliance, which is the best you can do with such poor circuit/appliance protection. The not so good result is you try them all and they all work fine. So now you have a faulty appliance, you don't know which, and you're going to carry on using it until it fails again, maybe worse next time.

Yes, well you don't understand it. But don't worry, that's quite common.

The design starts by looking to see where the failures tend to be. They tend to be in the appliances and appliance cord, i.e. the parts which get moved around, and not in the fixed wiring which is generally well protected from degrading effects. So to localise such failures, protection is applied at the start of the common failure path, which is the appliance plug. This has a big advantage that the protection is intimately associated with the item it protects, so when you have a faulty appliance, there is never any question of which appliance it is (ignoring RCD's, which are a later 'problem'), or of moving the faulty appliance to a different socket and continuing to use it.

Strange that the EU countries with radial circuits generally have twice as many electrical incidents as we do (and that's ignoring the ones with poor quality wiring).

Well, that's because prior to around 1970, it wass illegal to supply an appliance with a plug in case it was the wrong type, someone cut it off, and then stuck the resulting loose plug and exposed flex into a socket. That was just one tiny part of the problem of having multiple socket types. By 1970 (can't remember the exact year), judgement was that sockets other than

13A were now sufficiently rare that the law could be changed to require a BS1363 plug to be fitted to all appliances which were expected to be plugged in to a socket.

All new appliances nowadays are required to remain safe with 16A protection, so actually you can leave a 13A fuse in everything sold in last 10-20 years. Exceptions are old appliances with longer thinner flexes (which are no longer allowed), and extension cords, whose ratings are horribly complicated anyway, but you aren't going to dangerously overload any extension cord you buy today at 13A providing you fully unwind and don't cover it (there are other complications though).

But seems to be around twice as safe as most of its EU alternatives, fortunately for us.

Reply to
Andrew Gabriel

The only thing you demonstrate is that you fail to grasp the basic principles of our modern ring system, or even basic electrical safety principles. I'm sorry but I dont have the patience or the desire to continue this discussion.

NT

Reply to
bigcat

Yes theyre different issues, I was just responding to his unlikely vision of an unfused plug all radial system. How he intends to implement multiple fusing requirements into that I didnt even ask.

Good luck.

NT

Reply to
bigcat

On Sun, 24 Jul 2005 18:12:36 +0100,it is alleged that ":::Jerry::::" spake thusly in uk.d-i-y:

Nothing, also, irons then were probably 750w maximum, and not earthed, so technically other than the mechanical stress on the pendant fixture, nothing was wrong with doing that. Remember, older lampholders were more solidly built and could probably handle up to 5 amps without a major issue.

Reply to
Chip

,

that

without

What shade of grey is a 3amp fuse, and what shade of grey is a 13amp one, to someone with colour blindness or those with sight problems?...

Reply to
:::Jerry::::

HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.