Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
Posted Feb 9, 2024 19:12 UTC (Fri) by Wol (subscriber, #4433)In reply to: Quotes of the week: Theo de Raadt by khim
Parent article: Quotes of the week
> Why? Only UK have fuses in the plugs. The majority of the world only have them in the place where 60 ambs is separated into thinner wires.
So basically, it's EXACTLY the same as the UK. Everywhere you drop the ampage, you have a lower rated fuse. Oh - and in the UK once you leave the fuse box, everywhere is, I think, 20Amp wire until it leaves the house circuit.
And the reason for the ring main is, I can't remember the proof, but a ring main allows you to deliver more power, over a longer distance, with less copper.
> Some devices have additional fuses (computers often have them), but it's entirely optional and not needed for safety.
Try telling that to people who's houses have burnt down!
A portable radio needs, what, 0.2 Amps? What sort of damage is going to be caused by feeding 16Amps through it! These things are *supposed* to have a 3amp fuse (although often they have a 13). And they cause fires at regular intervals. One of the most famous examples being Windsor Castle. I think the Cutty Sark is another.
So it's very MUCH safety. Fires set furniture alight. Most furniture, if it burns, releases poison gas. Your sofa catches fire? You've probably got MINUTES to get out the house before you're dead from poisoning. Okay, most furniture is meant to be fire-resistant, but ...
Or what about expensive failures? You've gone away for a week, your radio in the kitchen fails (and they do), and takes out the fuse the day after you left. How much is that going to cost? You're probably looking at hundreds of pounds to fix all the damage.
You're welcome to think it's over the top. If I have an electrical problem, I'd rather it was confined to the smallest area possible, not taking out a large chunk of the house. I've had circuit breakers trip and take out a ring main. They cause grief. A LOT of grief. To me our regs give both safety and security. WELL WORTH IT.
Everything comes with fuses. We never even notice until something goes wrong. At which point, it's worth its weight in gold.
Cheers,
Wol
Posted Feb 9, 2024 19:44 UTC (Fri)
by khim (subscriber, #9252)
[Link] (22 responses)
How do you measure it? I couldn't find meaningful comparisons, but what I was able to find doesn't show UK superiority in that department. In fact most stats that could find say that fires are less of a problem for Norway or Germany than they are in UK. IOW: somehow “superior approach” with bazillion fuses everywhere that are designed to support wires that are too thin and weak to be usable in any other configuration don't provide extra-safety, but quite the opposite. Why would I have radio in the kitchen and why would it fail if I turn off power feed to my home when I'm leaving it for week?
Posted Feb 9, 2024 21:10 UTC (Fri)
by Wol (subscriber, #4433)
[Link]
> Why would I have radio in the kitchen and why would it fail if I turn off power feed to my home when I'm leaving it for week?
You're clearly not married, then ...
Okay, I've got a tv in the kitchen, not a radio, but ...
You turn off the pwer to the house for a week ... what happens to contents of the fridge and freezer? What happens to the tropical fish? What happens to, well, I'm sure people can think of other things ... the insurance insists I leave my central heating on - which needs electric ...
(And no, most of that lot is not my choice. But I have a family. It's not my decision to make ...)
Cheers,
Posted Feb 9, 2024 21:19 UTC (Fri)
by Wol (subscriber, #4433)
[Link] (20 responses)
> How do you measure it? I couldn't find meaningful comparisons, but what I was able to find doesn't show UK superiority in that department. In fact most stats that could find say that fires are less of a problem for Norway or Germany than they are in UK.
I said TO ME. I've never had a fire, and fires have never affected me (electrical fires, at least). I just don't want the entire house taken out, by an accident in, say, the garden. I would have thought that was obvious! And when that sort of thing DOES happen, it causes major grief!
So isolating a problem to the smallest possible area just MAKES SENSE. It makes sense for programming. It makes sense for electronics. Why shouldn't it make sense for household electrics!? (And with disabled people in the family, it's actually quite a serious issue - that HAS bitten me. BADLY!)
Cheers,
Posted Feb 10, 2024 17:15 UTC (Sat)
by khim (subscriber, #9252)
[Link] (19 responses)
Not always. It's all about the trade-offs. Same. It makes sense to do the sensible things and not to use, e.g. aluminium wires if you may afford copper. But putting bazillion fuses everywhere? That doesn't make sense. And it makes even less sense to insist that said fuses save anyone from anything unless we have proof. And no I feel myself safer when I have these is not an adequate reason: people's feelings about what is or is not working are, at best, unreliable and often flat out wrong.
Posted Feb 10, 2024 17:24 UTC (Sat)
by mb (subscriber, #50428)
[Link] (18 responses)
Come on. It's well understood how electricity works by 2024.
Posted Feb 10, 2024 17:37 UTC (Sat)
by khim (subscriber, #9252)
[Link] (17 responses)
It's only “that simple” when you ignore important parts of the problem. Then you have not one, but two solutions: And it's really not clear to me why do you believe having more potentially fallible protectors and thus more points of failure is superior solution. Bazillion fuzes… approach may be cheaper one, but it's entirely not clear to me why would it be more robust and safer. I know for a fact that in software design it often (but not always, it's all about trade-offs, as I have said) leads to more fragile and less reliable end result and I'm not sure why with household appliances it would be different.
Posted Feb 10, 2024 17:52 UTC (Sat)
by mb (subscriber, #50428)
[Link] (15 responses)
You should really really educate yourself about how energy distribution works and how the protection mechanisms work and (most important) what the job of those protection devices is.
Nobody is "filling the household with fuses" anywhere.
There are many different kinds of protection devices with many different characteristics.
Nobody is just randomly putting these everywhere.
Posted Feb 10, 2024 18:23 UTC (Sat)
by Wol (subscriber, #4433)
[Link] (1 responses)
When you have disabled people in the house who rely on electricity, the LAST thing you need is a short in the garage (caused by rain) taking out the house circuit breaker for one example.
Or you go away for a week, something trips, and you've just lost the entire contents of your freezers. Plural. And your wife is up in arms because none of her favourite tv programs recorded. Etc etc.
At the end of the day, KISS. And every where the maximum ampage drops, we have a fuse to enforce that drop. JUST LIKE THE REST OF EUROPE.
And I'd much rather spend a few quid on a few fuses than hundreds of pounds on UPSs for all my vulnerable appliances. That's not even a theoretical. I'VE BEEN BURNED (figuratively) BY THAT.
I'm not talking about theoretical benefits to "the general populace". I think our system works BECAUSE I'VE SEEN IT WORK *FOR* *ME*.
Oh - and did I say "KISS"? Which is simpler - some fuses in some leads so people have to remember to use the right lead in the right appliance, or a fuse in every lead so you can't get it wrong? Or a wiring system that will allow you to put an earthed plug in an unearthed socket but not an unearthed plug in an earthed socket (which *encourages* you to mess up)?
Cheers,
Posted Feb 10, 2024 18:25 UTC (Sat)
by corbet (editor, #1)
[Link]
Posted Feb 10, 2024 18:43 UTC (Sat)
by Wol (subscriber, #4433)
[Link] (12 responses)
Do we really want a *designed* current of 30Amps pouring from a socket - unfused - through a plug and wire designed for 13Amps? :-) Come to that, do we really want somebody having 30Amps flowing through their body if they touch a live wire! (Although a current of amps is actually less likely to kill you than a current of milli-amps - amps will burn but milli-amps will stop your heart.)
It would probably make more sense to insist on fused sockets, but that would then make them a lot more complex - especially if they're double sockets.
Cheers,
Posted Feb 10, 2024 20:08 UTC (Sat)
by pizza (subscriber, #46)
[Link] (10 responses)
There's more than one way to skin the proverbial cat.
In the US, what you described would be a violation of the National Electric Code. The circuit breaker must be sized for the lowest-rated portion of the circuit. Even if the wiring can handle 50A, if the socket(s) can only handle 15A, the breaker for that circuit must be no greater than 15A.
(This means that if two loads on the same circuit try to suck down 10A each, while that's fine from each socket's perspective, it's going to to pop your 15A breaker.)
Additionally, high-amperage circuits (water heater, HVAC, etc) are usually required to be dedicated to a single load.
> Which is cheaper, a couple of fuses at a couple of pennies each, or a hundred quid for another drum of cable (or more)?
At my local hardware store, 10/2 (30A) wire is nearly 3x the price of 14/2 (15A) wire ($0.92/ft vs $0.32/ft). So it's considerably cheaper to run two 15A circuits instead of one 30A.
Posted Feb 10, 2024 20:21 UTC (Sat)
by pizza (subscriber, #46)
[Link]
I should also point out that in the US, higher-amperage/voltage (>20A, >120V) plugs and sockets are physically incompatible with lower-amperage/voltage (<= 15A, 120V) ones. So you are physically prevented from plugging something only capable of safely handling 10A into a socket capable of delivering 30A.
Of course, nothing prevents you from buying a 240V 30A plug, using 26AWG (<2A) to connect a 120V electric kettle and setting your house on fire, but at that point it's darwinism.
Posted Feb 10, 2024 21:17 UTC (Sat)
by Wol (subscriber, #4433)
[Link] (8 responses)
Different code, same purpose. Don't forget we have a ring, so we're delivering 30Amps over two (I think it's) 20Amp wires. So the socket will be designed to cope with 15Amps coming in either side, and delivering 13Amps to the socket. In fact, I think single sockets are designed to the same standard as doubles, so the socket has to be capable of delivering 26Amps.
Although I get your point - what happens if the ring gets broken? I don't actually know.
> At my local hardware store, 10/2 (30A) wire is nearly 3x the price of 14/2 (15A) wire ($0.92/ft vs $0.32/ft). So it's considerably cheaper to run two 15A circuits instead of one 30A.
So a 30Amp ring will cost roughly one third the price of a 30Amp spur. And I can have 2 x 3KW heaters in my room compared to your one if you have a 15Amp spur :-) At a cost almost identical to yours. Why I would want two 3KW heaters I have no idea :-)
Cheers,
Posted Feb 11, 2024 8:59 UTC (Sun)
by khim (subscriber, #9252)
[Link] (7 responses)
Sorry, but no. Different code, different purposes. Yes. That allows you to save some metal. And allows you to make things cheaper. But, in turn, that mean more points of failure. Which means less reliable protection and more chances of fatal failure. That means that UK have cheap and convenient yet dangerous setup. That's simple logic. And then you start preaching safety and when I become surprised you explode and, again, explain how you have convenient yet more dangerous setup. Because I'm not even sure what we are discussing here. Just what people are trying to tell me when they say you should really really educate yourself about how energy distribution works? I know how energy distribution works, but I also know how it fails. Fires happen not when protectors work but when they fail. Fuse doesn't blow up when it should (often because someone become tired of replacing it all the time and user piece of wire instead of fuse) or protector doesn't disconnect what it supposed to disconnect. And wire designed for 5A received 16A or wire designed for 16A received 60A. Then it overheats and burns. Now, there are, basically, two ways of designing things: “UK” and “everyone else”. UK way is to use thin wires and then put fuses everywhere to proctect them. That's convenient, cheap, complicated and dangerous design. Because these fuses are very much needed there and if any if them will not work and wouldn't break connection in danger you risk damage, including, but not limited to fire damage. “Everyone else” uses approach that's less convenient, more expensive, but simple and safe. Thick wires everywhere means there are less points of failure and less points of failure means more safety overral. Now, you may argue your preference for convenience or your preference for safety, but it's just stupid to praise safety if you have cheap and convenient, but dangerous setup, don't you think? Now, about practicality: “everyone else” approach doesn't preclude you to add more fuses if you wish. E.g. you may have connector to your garage which includes fuse and thus prevents your house from being powered-off after raid. But, and that's critical difference, that't convenience fuse, if it fails you are still safe. You house would be disconnected yet it wouldn't burn, because the main fuse would protect you.
Posted Feb 11, 2024 9:25 UTC (Sun)
by mgb (guest, #3226)
[Link] (5 responses)
¯\_(ツ)_/¯
P.S. Unlike US breakers, UK fuses do not sometimes fail to blow when overloaded - too much current through a thin wire vaporizes it reliably, quickly, and safely. However replacing a blown fuse takes a couple of minutes longer than flipping a tripped breaker.
Posted Feb 11, 2024 10:09 UTC (Sun)
by khim (subscriber, #9252)
[Link] (1 responses)
If no one ever mixes them up, no one puts some piece of wire “to make the damn thing work, because I need it now” and so on. Well, maybe UK citizens are living in a different universe and they never make any mistakes, but then why do they need these fuses in the first place? I don't even use ani-virus (except what Microsoft shoves down my throat) and I don't see the point of it (that abomination Microsoft calls protector only ever acts on me when I compile programs with non-standard settings and I've never seen it acting upon real threat). But it's like “convenience fuse” on the extender in non-UK setup: it may help you if you are not careful enough, but if you built your whole security system on the assumption that anti-virus never fails and always protects you… then you are doing it wrong.
Posted Feb 11, 2024 12:24 UTC (Sun)
by mgb (guest, #3226)
[Link]
Oddly enough, since this is LWN, I don't have Microsoft pushing anything on me - none of our laptops, servers, or virtual servers run Windows.
Posted Feb 11, 2024 14:57 UTC (Sun)
by pizza (subscriber, #46)
[Link] (1 responses)
...Have look at some of Loius Rossman's rants on fuses that aren't what they claim to be. If you think UK plugs aren't full of similarly dodgy fuses then I have a bridge in London to sell you...
FWIW I grew up in a place that used UK-style fused plugs (on radial, not ring circuits), and have personally witnessed plenty of fuses/plugs/sockets that *melted* but didn't blow, only "failing" when something melted to the point where the contacts no longer contacted, or causing a short that tripped the upstream breaker/fuse.
So personally, I place far more trust in dual-action circuit breakers [1] than fuses.
[1] A thermal component that trips if the sustained current is too high for too long, and a magnetic component that trips if the current suddenly spikes. Then there are the Ground Fault and Arc Fault breakers that add additional protections.
Posted Feb 11, 2024 16:47 UTC (Sun)
by Wol (subscriber, #4433)
[Link]
You'd be surprised then ...
Okay, from what you've said about dodgy Chinese suppliers, you could be right, but your typical UK plug nowadays is a sealed unit where if the fuse blows you just replace the cable. Your typical UK consumer today wouldn't have a clue how to cut off and replace a moulded plug. Even where you can replace the fuse, they wouldn't have a clue how to do that!
(And we did have a bridge in London we sold to you :-)
Cheers,
Posted Feb 11, 2024 17:11 UTC (Sun)
by farnz (subscriber, #17727)
[Link]
UK fuses also fail to blow when overload - too much current through a thin wire heats it, yes, but it does not always vaporise; and even when it does vaporise, it can do so by coating "non-conductive" parts of the fuse in metal, resulting in the fuse carrying more current than it was designed to do (since the new coating is shorter and thus thicker than the wire was).
Both of these are rare failure modes, but they exist; there's a reason why BS 7671 now recommends breakers over fuses, because breakers (when well-constructed) are more reliable than fuses.
Posted Feb 11, 2024 10:27 UTC (Sun)
by mb (subscriber, #50428)
[Link]
No.
Posted Feb 10, 2024 21:14 UTC (Sat)
by songmaster (subscriber, #1748)
[Link]
Posted Feb 10, 2024 18:28 UTC (Sat)
by Wol (subscriber, #4433)
[Link]
> You have fill your household with fuses, or…
Changing the wire setup means adding extra wires to achieve the same carrying capacity.
Which is cheaper, a couple of fuses at a couple of pennies each, or a hundred quid for another drum of cable (or more)?
Cheers,
> To me our regs give both safety and security. WELL WORTH IT.
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
Wol
Quotes of the week: Theo de Raadt
Wol
> It makes sense for programming.
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
If the wire setup (which includes its environment) can't carry the max short circuit current, we need a fuse in front of it, to drop down the max short circuit current.
It's that simple.
> It's that simple.
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
They are added at places which follow certain rules. These rules are based on electricity physics and thermal physics.
Fuse != fuse.
Breaker != breaker.
RCD != RCD.
etc. etc...
Not even the UK style of putting them into every connector is random by any means.
Quotes of the week: Theo de Raadt
Wol
At this point, I'm thinking that this conversation has gone pretty far afield and that there's little to be gained by continuing it. Maybe it's time to stop?
I think we've blown the fuse
Quotes of the week: Theo de Raadt
Wol
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
Wol
> Different code, same purpose.
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
> Unlike US breakers, UK fuses do not sometimes fail to blow when overloaded - too much current through a thin wire vaporizes it reliably, quickly, and safely.
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
Wol
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
Can you please stop it? Thanks.
Quotes of the week: Theo de Raadt
Quotes of the week: Theo de Raadt
> You may change the wire setup
Wol