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The electrical hazard isn't that big. In a traditional electrical Christmas candle chain, the individual candle lights are coupled in series, so that the 240 V AC distributed over 24 candle lights make the voltage drop over each of them about 10 V. You can see the series coupling in that unscrewing any one of the lights make the entire chain go black. In theory you could by accident create a shortcut between the first and the last light in the chain; that would be a voltage similar to that of the outlet where it is plugged in. I never heard of that happening.
Today, most people use about five hundred LED bulbs rather than 24 candle lights, with an adapter box providing maybe 12 V, maybe only 5. Not really life threatening.
One of our friends 30 year ago still used live candles. They had a fair number of spray bottles available all around the tree. Their sons had an awe for the tree when the candles were lit that I found impressing, yet not something that I wanted to transfer to my children.
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trønderen wrote: The electrical hazard isn't that big.
I can imagine it has improved over the years. The last Christmas lights I placed on a tree only had that little two-pronged plug. Those were the times when we'd scoff at wearing a helmet while skateboarding in concrete parking lots, or jumping over a set of stairs. Our tolerance for risking danger back then was a lot more casual than it is now. Either way, I'll skip the candles for LEDs.
trønderen wrote: One of our friends 30 year ago still used live candles. They had a fair number of spray bottles available all around the tree. Their sons had an awe for the tree when the candles were lit that I found impressing, yet not something that I wanted to transfer to my children.
Wow. That's nuts. You can understand why the whole concept of setting up Christmas trees is so baffling to me. I've gotten some good answers though.
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trønderen wrote: In a traditional electrical Christmas candle chain,
I meant real candles, not "electric" candles.
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Sure. I was referring to your first paragraph - I wanted to point out that electrical candles are not as life threatening as you seem to think.
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Marc Clifton wrote: using real candles, which is what people traditionally did
Yes, I cannot believe that. If you're going to append lit candles to a tree located inside your house, there must be a really good reason why you'd risk so much danger to do so.
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Christmas trees arrived before electricity.
Besides, in the early days of electricity, you wouldn't believe how people handled it! They knew how to handle open flame, having lived with it for thousands of years. Even today, lots of fires are caused by people not knowing how to handle it.
Having a modern city-guy put real candles on a tree would probably scare the sh*t out of me. A 90-year old great grandpa who learned to lit both the oven and the open fireplace when he was five years old would make me feel much more confident. Modern people do not know how to handle open fire. A kid may still learn from the great grandpa, but I fear that the young adult would shrug at the old man and rather check if there are some YT videos that can show him how modern people would do it.
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trønderen wrote: Having a modern city-guy put real candles on a tree would probably scare the sh*t out of me.
That made me laugh. I know a bit about the origins of Christmas trees, but who was responsible for coming up with the idea of lighting candles and appending them to a flammable plant inside their house? Perhaps people may have been more familiar with fire science in the past, but it's beyond any person's ability to avoid accidents. The thing about fire is that you don't realize it's out of control until it's too late. I can attest to that. It's one thing to embrace nature, but who came up with the candle idea? The meaning and significance behind that practice are still a mystery to me. Killing a tree, abducting it, and decorating it with shiny objects and fire is a strange thing to do. I can see why you'd like to have a tree inside your home, but dressing it up after you kill it doesn't seem to be in line with the Pagan philosophy of embracing nature. If you do that to a tree, you might as well lure farm animals into your living room and decorate them with all sorts of obscure ornaments and fire, too. Set a few chickens on fire and watch them run around the living room in a ball of flames. What a wonderful time of year. 
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Steve Raw wrote: Set a few chickens on fire and watch them run around the living room in a ball of flames.
Why not go whole hog, and set a pig on fire? Roasting meat smells a lot better than burning feathers.
(For the humour-impaired, I certainly do not advocate burning pigs, chickens, or any other creature alive)
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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For the serious side: Have you ever tried yourself, or been to a party where they roast a whole pig? Or lamb, or calf or whatever?
It takes a long, long time to roast it! With lots of intense heat. If you are talking about a small piglet, it can be baked at moderate temperature for a few hours, but for a large hog, you will probably cut off slices as they have been roasted, to let the heat in to the meat that is not yet done. Roasting a pig over a bed of charcoal is suitable for a celebration that runs all day, with people coming to have their serving(s) over a period of many hours.
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I sit corrected.
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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Yes, I've attended a Hawaiian luau. It was a lot of fun.
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google videos for “turkey frying disasters” to reaffirm your skepticism!
Biggest mistakes:
- Too close to structure
- Too much oil in pot
- Turkey is still frozen
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Steve Raw wrote: Do you ever take a step back and think
about the idea of a Christmas tree?
No I haven't put up a tree in probably 30yrs.
As the aircraft designer said, "Simplicate and add lightness".
PartsBin an Electronics Part Organizer - Release Version 1.3.0 JaxCoder.com
Latest Article: SimpleWizardUpdate
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It's been many years for me as well. I do find Christmas trees to be confounding, but that doesn't mean I don't like them.
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let's not forget to tip the waitresses . then there's the Easter Bunny . but that of course is a few months away . so we have something to look forward to .
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No fuse? Two prongs? 120V?
I don't really get any of these things. Here in the UK every plug has a fuse in it, every plug has three pins (not always used for 'double insulated' appliances) and a punchy 240v flows through those terminals. No fuse? Why doesn't everything burn down with electrical failures? No earth, how do you protect metal items? 120v - So you need twice the current/twice the area of wire per watt? Do you have RCD protection, so any earth leakage will cut the power?
I take your point!
Regards,
Rob Philpott.
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UK is the only country I know of which (often) has fuses in the socket. (And the only country to use those huge sockets fuse or not.)
The common solution is to have a central fuse box - that is, in the other end of the cable. It doesn't make that much difference. Except that the central fuse is dimensioned according to the cable running to the socket, to keep it from overheating and causing a fire.
If there were no central fuse, and the cabling was 1.5 sqmm (capable of handling 10 A), then you plug in a 4 kW heater with a 20 A fuse, this fuse will not prevent the cable up to the socket from overheating. So I guess that you have a central fuse box as well. Then you have a cable (from the fuse box to the socket with one fuse in each end. Having fuses in both ends won't prevent that many fires compared to a cable with only a fuse in the central end.
This plug with a fuse is/was closely associated with the "ring circuit" wiring layout, which is something else I have never heard of outside the UK.
The British plug does have its advantages over Schuko, say, used in most European countries. One is the the mechanical strength. Compare it to the original USB B plug compared to mini, micro and C plugs - people rejected the B plug, crying for something smaller and more lightweight.
Another: It is polarized - the Schuko (as well as the ungrounded US plug) is not, even though the most common power supply ("TN") is asymmetric: One pin is "live", the other is "neutral". If you turn the plug 180 degrees around, live and neutral switches, on the plug side. So you really should always use two-pole switches on the plug side; they are almost always single-pole.
So I am not too exited about neither Schuko or the US plug, we should have learn some lessons from the UK, but without adopting that strange "ring circuit" layout and the cast iron (or is it lead?) plugs.
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trønderen wrote: UK is the only country I know of which (often) has fuses in the socket. (And the only country to use those huge sockets fuse or not.)
My mother-in-law's house in South Africa also used giant plugs, albeit of a design different to the British standard (three round prongs, with the ground larger than the other two). I understand that the modern South African standard uses something closer to the European standard.
I don't remember off-hand whether the sockets were fused.
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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South African plugs were almost identical to BS546 British "three pin round" plugs which preceded the BS1363 "three pin square (sic)" plugs that we currently use domestically.
BS546 plugs are still widely found in theatres, to discriminate between dimmer circuits and standard circuits. They have advantage, in the theatre context, of no fuse in the plug to blow; the circuits are individually fused centrally.
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Have you ever broke a Schuko?
Never wear down a mini, micro or C USB plug yet (mostly plugging C these days as headphones changed connector), but B, used mainly for printers, placed on the back of the printer, multiply the pain of the fractional dimension of the A by two.
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Rob Philpott wrote: I don't really get any of these things. Here in the UK every plug has a fuse in it, every plug has three pins (not always used for 'double insulated' appliances) and a punchy 240v flows through those terminals.
I know what you mean. I lived in Britain for just under 6 months. I remember the plugs were entirely different from what we have in the US. I needed to buy an array of plug adapters designed for multiple types of plugs for various foreign countries. That allowed me to operate my electrical devices. I don't know if the adapters changed the volts and amps of the outlet's electricity, but I assume they did. Otherwise, I suspect my electronic devices would short-circuit and die.
In the US, the standard power for residential applications is 120 volts and 15 amps. Multiplied together, these give us 1800 watts. It's an alternating current that cycles 60 times per second.
I know in the UK, 240 volts is the standard, but I've long forgotten how many amps there are. I assume that the current cycles are 60 times per second, but I don't know. I'll have to Google that.
Here's a link: England residential electricity volts amps cycles - Google Search[^]
This is one of the results that popped up. Sounds as though it's correct.
A standard UK plug socket typically supplies electricity at 230 volts AC and up to 13 amps. Strictly speaking, 32A if fed via a ring main or 20A if fed from a radial circuit. The plug is the limiting factor, not the socket. Plugtops (the correct term) are fitted with a maximum of a 13A fuse.Sep 28, 2017
One of the search results stated that in the UK, AC electrical current cycles at 30 times per second.
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Steve Raw wrote: I don't know if the adapters changed the volts and amps of the outlet's electricity, but I assume they did.
A lot of newer electronic devices with (built-in) semiconductor based power supplies can handle anything from 100 to 250 V. So you charge your smartphone, plug in your portable radio etc. They work fine; you think that it will work fine with any sort of equipment, and plug in something that does not have any built-in regulator, or one based on a transformer, and it goes Pooof!.
If your adapter plug appears to be nothing more than a plug with a "US style" socket, and an English (or other) plug, with no apparent "box" for electronics or a small transformer, do not assume that it converts 240V to 120V! You can get small transformers; they are marked with the in and out voltages and maximum effect. I have got one transformer bases, it is rated for 50 W, and one semiconductor based, rated for 1000 W. Neither can handle plugs with a ground pin, on either side. (Since all new houses, and major upgrades to the electric cabling of older houses, are all grounded, so both my adapters are now useless!)
I know in the UK, 240 volts is the standard, but I've long forgotten how many amps there are. The actual current, in amps, depends on the consuming apparatus. The rating of the plug, socket or cable is the maximum load, determined essentially by the cable dimension. 1.5 sqmm conductors can handle 10A, and the central fuse box has a 10A fuse. 2.5 sqmm conductors can handle 16A, with a 16A fuse in the box. For 25A, for electric stoves, 4 sqmm cable is used. Nowadays, the fuses are electronic, but in old houses you can still see those ceramic screw-in fuses: Fuses for higher currents has a wider throat, so a 16A fuse will not fit in a 10A socket. In Norway, the old standard was 1.5 sqmm cables, for a max load of 10A. The last 25-30 years (? I am not sure when the change came about), 2.5 sqmm, 16 A, became the standard.
The socket/plug must also be capable of handling the maximum load. In most of Europe, using "Schuko" plugs, all of it is made to handle 16A. For higher effects, there are special plugs, often for three-phase power.
GB is a little by itself, with its mammoth plugs and built-in fuse, and "ring circuits" which are unheard of in the rest of Europe. The fuse is usually 3, 5 or 13A. As standard voltage in GB is 240V, but 230V in the rest of Europe, the difference in power handling (240V * 13A = 3120, vs. 230V * 16A = 3680) isn't that much different from GB to the rest of Europe.
Note that a lot of apparatus, especially motorized stuff, have fuses to keep the motor from burning off in case of overload. It is a lot cheaper to replace a fuse than to replace the motor! The size of this fuse is set to what the motor can handle, which is usually a lot lower than the max rating for the cable (such as 13 or 16A).
One of the search results stated that in the UK, AC electrical current cycles at 30 times per second. All of Europe, including GB, uses 50 Hz AC. Nowadays, all of Europe is perfectly synchronized; they all hit the peak voltage at the same time. Norway had an all synchronized power network since the late 1950s; power people from other countries said "You guys are crazy, synchronizing power stations 2000 km apart!" - but we did. Today, with atomic clocks and power semiconductors, it is a trivial matter.
There are some oddballs, like the Norwegian railroad system (which is mostly electrified) for historical reasons run on 16 2/3 Hz AC, so they must either have their own power stations (which they partly have), or they must convert from the standard 50 Hz. But if you look up the various voltages, AC frequencies or DC, and ways of getting the electricity to the locomotive (pentagraph, third rail, ...), it is a big mess all over the world, and a mess in Europe. Many countries have two or three different alternatives. Norwegian subways use 750V DC from a third rail, while (long distance) trains use 15,000V, 16 2/3 Hz AC from an overhead cable (catenary), but at least four other systems are used in Europe.
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Yeah, that 230v is a misnomer. It's still 240v but we label everything as 230v and add a tolerance to harmonise with Europe's 220v. So we've got 240, they've got 220 and we all call it 230!
50Hz. Ah, the 50Hz hum. You get to recognise it, whenever a jack plug isn't in properly or something. I've not heard the US 60Hz, but I guess your mains hum must be a couple of semitones higher (I could work it out, but can't be bothered!)
1800W - that's not a lot. So the most common fuse here is 13A which gives an appliance circa 3KW. I'm told that a 13a fuse will actually blow at about 20 amps. My ovens require a 16A fuse, but I've just stuck a 13A socket on them and they work fine, which is handy as otherwise I'd have to go all the way back to the consumer unit.
I, and probably some other weirdos, feel some affection for our 3 pin plug. It heralds from a time when the UK did things properly (now we just do everything as cheaply as possible or better yet import it). The earth pin is longer than the live/neutral, and the extra length opens shutters in the socket which prevents kids sticking metal things in the sockets. Everything is fused and earthed. It's very good!
But coming back to the 120v, I wonder what that feels like. Having had more than my fair share of connections to 240v, I can say it certainly wakes you up (at a minimum). Actually, I had a near fatal shock when I was six where I couldn't let go which burned a hole in my hand. 240v is lethal, your chances have to be much better at 120v, so maybe the need for all the clever stuff of the three pin plug isn't needed.
I don't know why I find all this so interesting.... 
Regards,
Rob Philpott.
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Rob Philpott wrote: But coming back to the 120v, I wonder what that feels like.
It's happened to me. I felt quite shocked. Ha! 
That was awful, wasn't it? I deserve to be berated.
Seriously though, when I was around age 4, I somehow received an electric shock while trying to push my finger into an electrical socket. That's not supposed to happen. I didn't understand electricity or electrical sockets. I thought that something sharp inside the socket had suddenly jumped out and jabbed me. I concluded that an ill-tempered tiny little animal lived inside. I never tried it again.
I have also been shocked inadvertently by making skin contact with the power cable to the vacuum cleaner. Its protective sheath was previously mangled by the vacuum cleaner itself, exposing the wires. The shock certainly got my attention, but I don't remember it being particularly painful.
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Most of Norway uses a power distribution system called "IT", Isolated Terra (i.e. ground), rather than "TN", Terra and Neutral. IT is "delta" 3-phase: There is no neutral; you'll find 230V between two triangle corners. TN uses "star" 3-phase, with 230V from a corner to a center neutral, 400V between triangle corners.
With IT, the two pins giving you 230V is supposed to be symmetric around ground potential (otherwise you have a ground problem that should be fixed). So e.g. if one of the conductors shortcut to the shield of the apparatus, you touch it and ground at the same time, you will experience roughly half the voltage. To get a 230V shock, you would have to touch both conductors at the same time, before the fuse blows.
In a TN system, you will have a 230V blow if you touch any conductor, and you are grounded. If you touch two corners of the star, i.e. two live conductors on different phases, you get a 400V blow.
Several times I have tried to make power supply people explain to me what is so great about TN, what's in it for me as a consumer. They invariably come up with a lot of advantages as seen from the power station, things that I do not see as a consumer. I am currently on an IT network, and I see no reason to fight for an "upgrade" to TN. (It won't happen anyway, as it would require all new cabling: IT manages with 3 conductors, TN requires 4 or 5, depending on whether you want a separate ground conductor.
The only issue with IT is for those who want to install a fast 3-phase charger for their electric cars. Very few cars have onboard chargers that can handle 3*230V, almost all are for 3*400V. As I do not yet have an electric car, it doesn't matter much. Besides, an 11 or 22 kW single-phase charger is fast enough for me (with less wear on the batteries). I much prefer a lower shock in case of a short circuit somewhere.
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