120 V or 240 V Mains - which voltage is better?

Myriad said:
If it's just one more choice added onto the list for wiring a new circuit, then it's not really much different. It has the advantage of being able to change your mind later about whether you're using the new outlet(s) for 120 or 240 VAC equipment. But unless those 240 VAC appliances come wired with those 5-prong plugs, it's also a drawback. (I'd consider it if wiring a new workshop, but first I'd have to research whether tools equipped with those plugs are available. Also, whether the electrical code allows them.)
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These are valid considerations. I am just surprised that nobody has thought of this already if power limitations are an issue. In most parts of the house they would not be necessary but they would be a boon where they were (especially if a standard 120V plug can be inserted into them).

I don't know if washing machines or water heaters are hard wired in the US but if they use a plug and socket, then from the links that bruto posted earlier, you are looking at some pretty specialized (ie expensive) plugs and sockets anyway.

Myriad said:
There are many many available standards that are objectively superior to the ones currently in use, but there's no economical path from the status quo to the superior standard. Imperial units in U.S. fittings, fasteners, machinery, and tools. "Positive" and "negative" in electronic notation. Probably too many to count in IT and digital communications.
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No such a valid concern in this context. Australia was forced to go metric by the government and although it was an unnecessary expense, it wasn't disastrous (though for a while, I had to have both imperial and metric spanners).

Nobody would be forced to use any particular plug and socket. You can use any one that is up to code.
 
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psionl0 said:
Nobody would be forced to use any particular plug and socket. You can use any one that is up to code.
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Then it's chicken and egg, and the appliance manfuacturers can't drive adoption. It would have to start on the home side, but there it's more expensive over 2-conductor solutions from cable, panel, labor, and box fill perspectives. Anyone trying to cut costs is going to stay far away.
 
psionl0 said:
So you weren't explaining why it isn't?
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Yes, I was explaining why it isn't, in part, which is not quite the same as explaining why it couldn't. Standards in the US are set by industry, which has no true authority. Localities setting up codes tend to go with industry standards, which tend toward improvement but are not usually very fast, and Americans have a dislike of retroactive standards. The result is a mess. Many things that could be done aren't.

Part of what I was explaining, which you are free to dismiss, was for the possible benefit of other non-USA persons who may not be familiar with the way power systems here work.

By the way, to address a later issue, just for information. Washers and dryers are generally not hard wired. Washing machines generally use an ordinary outlet, though I think most modern standards call for it to be on a circuit of its own, and may now also call for it to be a GFCI. All the washers I've installed in the last many years have included clamps and wires for a hard ground to a water pipe in addition. Dryers are wired also on an individual 30 amp 240 volt circuit (unless they're gas dryers, of course, whose electrical part goes to the normal 120 volt outlet). The trick here is that the dryers themselves do not come with a cable. So, presuming that you're doing it yourself, you first determine what kind of outlet you already have, and then buy the correct cable (either three or four prong, depending mostly on age of the outlet).
 
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Mexico runs on an antiquated system that is based off the US system. Your main can be 1 - 3 phase and it can be split into one phase if you desire.

Most all residential is 110 feed and code is quite lax, it mostly applies to commercial builds. At home any damn thing that works can be used, depending on how much you like little kids.

My home is closer to basic US code and outlets
The good ones and all have cover plates. What I replaced wasn't so good.

The better bits ran me a lot more money but it has been well worth it. I had to replace only two light switches in our time here.

The old house was a Simpsons level of bad wiring and a mix of 50 years of crap level parts in states of decay. No fuses or cutoff switch at all. I added that in my time there.

My son got a safer setting to grow up in.
 
On careful reflection, I can't remember ever having an electrical appliance that didn't work off a 13 amp square pin socket. They're pretty much universal in the UK these days for domestic use.

Dave
 
Dave Rogers said:
On careful reflection, I can't remember ever having an electrical appliance that didn't work off a 13 amp square pin socket. They're pretty much universal in the UK these days for domestic use.

Dave
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Even range and dryer? I could add central AC, but my understanding it that isn’t common.
 
Been a while since I saw the UK, so can't say about current practices there, but in Australia, the 10A socket is the standard, with 15A seen occasionally... usually for specific appliances or in workshops/sheds (for welders and the like)

Ranges are always hardwired here (except gas, they usually have a 10A socket for the controls) usually in 4mm or 6mm depending on number/size of elements (although you can get 'camping' two burner counter top units sometimes seen in single bedroom flats etc, they are a 10A plug)

Same with central or split cycle aircons, always fixed cables...
'Window rattlers' are 10A for smaller units, or 15A for larger ones- usually on their own circuit and breaker

Dryers are a 10A for domestics (some commercial dryers use 15A's) and are always supplied with lead and plug fitted, as indeed is any non fixed or 'semi portable' appliances.... no separate circuit required however (here ALL circuits- power and light are required to have a ground leakage breaker- older systems are required to be upgraded to them any time any work is done on the property)

Washers, driers, 'window rattler' aircons- always come with lead and plug fitted (indeed under Australian Standards, 'home handyman' fitting of leads, plugs etc is against the law, and can possibly land you with a fine- anything except changing a bulb or tube is a big nono- electrician required...
 
In urban areas it makes sense to have that type of law, I am sure out on remote locations a lot of home fixes are DIY.
 
Dabop said:
Been a while since I saw the UK, so can't say about current practices there, but in Australia, the 10A socket is the standard, with 15A seen occasionally... usually for specific appliances or in workshops/sheds (for welders and the like)

Ranges are always hardwired here (except gas, they usually have a 10A socket for the controls) usually in 4mm or 6mm depending on number/size of elements (although you can get 'camping' two burner counter top units sometimes seen in single bedroom flats etc, they are a 10A plug)

Same with central or split cycle aircons, always fixed cables...
'Window rattlers' are 10A for smaller units, or 15A for larger ones- usually on their own circuit and breaker

Dryers are a 10A for domestics (some commercial dryers use 15A's) and are always supplied with lead and plug fitted, as indeed is any non fixed or 'semi portable' appliances.... no separate circuit required however (here ALL circuits- power and light are required to have a ground leakage breaker- older systems are required to be upgraded to them any time any work is done on the property)

Washers, driers, 'window rattler' aircons- always come with lead and plug fitted (indeed under Australian Standards, 'home handyman' fitting of leads, plugs etc is against the law, and can possibly land you with a fine- anything except changing a bulb or tube is a big nono- electrician required...
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So if you require an electrician anyway the USAsian can get the electrician to hook up 220V at 30A (at least).

After a quick perusal of Australian Washing Machines I see the Aussies have gone full Eurotard. Which is, I guess, why one poster is so obsessed with putting the electric kettle on? Anyway, North American Washing Machines hook directly into the taps (both hot and cold) so no waiting around for the EU certified Energy Saver Washing Machine to heat up the water inside the machine (with its pathetic 240V 10A heating element) to 90C to do whites. Whites take about as long as colors! Or is that colours! Bwahahahahahaha. Cough ...
 
Elagabalus said:
So if you require an electrician anyway the USAsian can get the electrician to hook up 220V at 30A (at least).

After a quick perusal of Australian Washing Machines I see the Aussies have gone full Eurotard. Which is, I guess, why one poster is so obsessed with putting the electric kettle on? Anyway, North American Washing Machines hook directly into the taps (both hot and cold) so no waiting around for the EU certified Energy Saver Washing Machine to heat up the water inside the machine (with its pathetic 240V 10A heating element) to 90C to do whites. Whites take about as long as colors! Or is that colours! Bwahahahahahaha. Cough ...
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Hm, still better then having to deal with electrical nonsense found in USA... (even Italians have more sense then you and their electrical wiring and sockets are crazy)
 
Dabop said:
(indeed under Australian Standards, 'home handyman' fitting of leads, plugs etc is against the law, and can possibly land you with a fine- anything except changing a bulb or tube is a big nono- electrician required...
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Heh, my most recent sub woofer was wireless. That would have been terrific if it didn't need to be plugged into a power outlet. Worse, the power cord was so short that it wouldn't have reached any power point. Worser still, it used a special brand of plug that went into the back of the unit so there was no buying a longer cord off the shelf.

My only option was to splice an extra length of cable into the cord. :eusa_shhh:
 
psionl0 said:
Heh, my most recent sub woofer was wireless. That would have been terrific if it didn't need to be plugged into a power outlet. Worse, the power cord was so short that it wouldn't have reached any power point. Worser still, it used a special brand of plug that went into the back of the unit so there was no buying a longer cord off the shelf.

My only option was to splice an extra length of cable into the cord. :eusa_shhh:
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When faced with similar problems here (many things have cords too short) our usual solution would be an extension cord at the other end. Is there some reason in your case why that couldn't be done?
 
bruto said:
When faced with similar problems here (many things have cords too short) our usual solution would be an extension cord at the other end. Is there some reason in your case why that couldn't be done?
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Classic cases of "spoiling the ship for a ha'porth of tar".

In my case, the cord had to run through some tight spaces which didn't really accommodate a plug and socket in the middle.
 
psionl0 said:
Classic cases of "spoiling the ship for a ha'porth of tar".

In my case, the cord had to run through some tight spaces which didn't really accommodate a plug and socket in the middle.
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That makes sense, then.

WRT cords too short, there was a period in the 1970's, coinciding with a copper shortage, when power tool manufacturers apparently decided to economize by putting little stub cords on tools. I suppose, along with the economy angle, they figured most tools need an extension cord anyway. Consumers, of course, hated it and the trend did not last long. One of the things they sort of forgot to take into account was the fact that extension cords pull apart easily unless they're knotted. It's one thing to have an extension at the end of a four foot cord somewhere behind you, and a whole lot different to have the plug six inches from the handle of a tool, where not only is it in the way, and likely to pull out, but deadly dangerous if it's part of the way out. Nowadays most of the power tools with cords that I see have nice long ones again.

A good exception is hedge clippers, which often have a plug recessed into the handle, and no cord at all. The assumption here is that you will clip through the cord at some time, so it's your problem now.
 
bruto said:
A good exception is hedge clippers, which often have a plug recessed into the handle, and no cord at all. The assumption here is that you will clip through the cord at some time, so it's your problem now.
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And I've done that. The hedge clippers also had an arrangement to snap the cord into to stop the plug pulling out. It was somewhat helpful. Then I got a battery hedge clipper, for the little I needed it. Now I just have a yard man.
 
Dave Rogers said:
Oh, yeah, cookers are hard-wired in; sorry, I forgot that, because until this year I've always had gas cookers. Normal domestic tumble dryers work off a single standard 13A 240V socket.



Dave
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Quite a few cookers can now run from a standard plug socket and induction hobs as well. A normal plug in induction hob is OK unless you want to use all 4 plates on full power all at once.
 
psionl0 said:
Heh, my most recent sub woofer was wireless. That would have been terrific if it didn't need to be plugged into a power outlet. Worse, the power cord was so short that it wouldn't have reached any power point. Worser still, it used a special brand of plug that went into the back of the unit so there was no buying a longer cord off the shelf.
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You're going to have to run that by me again.

If it plugs "into a power outlet" then it could use a normal extension cord. It matters not what the plug that goes into the device is.

Are you merely saying that you do not like the look of 2 cords joined together and that you prefer one cord?
 
Speedskater said:
While not as common as 15A receptacles, 15/20A receptacles are seen in kitchens, bathrooms & laundry rooms. That would be a 2400W max.
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IIRC, the plug for 20A appliances has one prong horizontal (I don't remember whether it's hot or neutral. Most 20A sockets I have seen are constructed so that they will take either type of plug.
 
lomiller said:
Even range and dryer? I could add central AC, but my understanding it that isn’t common.
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Full size Ranges (cookers in the UK) are hard wired into a dedicated 20A ring with it's own fuse or RCD, depending on the age of the wiring, and a wall switch (in addition to controls on the oven and/or hob).

Washing machines, tumble driers, dishwashers, fridges, microwave ovens, countertop halogen ovens, toasters, kettles, pizza makers, etc all use the standard three pin plug.
 
Dave Rogers said:
On careful reflection, I can't remember ever having an electrical appliance that didn't work off a 13 amp square pin socket. They're pretty much universal in the UK these days for domestic use.

Dave
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Your cooker. :)

That said, I'm just under fifty and I can just about remember the council house I grew up in having a different type of plug, a circular three pin with a round center earth pin and a rectangular live and neutral either side in a straight line. I still have an appliance (a radiant heater that would never pass H&S legislation these days but can heat a freezing room in minutes) that I remember being fitted with one. I've also encountered small, round pinned 3A plugs in a couple of places, the last was a Harvester Restaurant less than five years ago, but these are pretty much exclusively used for low power lighting. They were used in pubs to stop people unplugging the lamps to either plug in something else... Or steal the lamps.
 
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P.J. Denyer said:
… I'm just under fifty and I can just about remember the council house I grew up in having a different type of plug, a circular three pin with a round center earth pin and a rectangular live and neutral either side in a straight line. I still have an appliance (a radiant heater that would never pass H&S legislation these days but can heat a freezing room in minutes) that I remember being fitted with one. I've also encountered small, round pinned 3A plugs in a couple of places, the last was a Harvester Restaurant less than five years ago, but these are pretty much exclusively used for low power lighting. They were used in pubs to stop people unplugging the lamps to either plug in something else... Or steal the lamps.
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Those unfused 3 round pin 15A and 5A plugs were the UK standard until the fused 13A version arrived but that was not long after the war. They remained in UK use for stuff like theatrical lighting rigs and they're still used in S. African and India. Maybe other places too. My parents' 1930s house still has a bunch of those outlets but they're not live any more (though they were when I was a kid in the '70s).
 
bruto said:
... One of the things they sort of forgot to take into account was the fact that extension cords pull apart easily unless they're knotted. ...
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Oddly enough, I used to have a bunch of fold-over plastic covers to prevent that from happening. They were very cheap, perhaps a dollar for a packet of ten?

I'm struggling to think if I could find one now, because I don't have any short-cord power tools anymore...

(They're still around, but cost $5 ea now!)

https://www.bunnings.com.au/hpm-extension-lead-safety-cord-lock_p4337970
 
Stuff that amuses me: "Cooker". In the USA it's a "stove" or "range". We only have "slow cookers".
Somewhere beneath my propane cooktop is the wiring for an electric one, or electric range. The breaker for that is off. But at least we have the option if we want to change in the future.
Back about 1980, the "slide in" range in our first house expired. I probably could have gotten an element, but it was "avocado" in color, courtesy of the late 1960's, and my wife wanted it gone. I pulled it out, modified the cabinetry, and installed a new freestanding one. The slide-in was hard wired, I had to install a 240V receptacle for it. I also did some other wiring in that house. As far as I know, it hasn't burned down yet.

I haven't yet done any wiring in our new house. Emphasis on "yet".
 
bruto said:
The neutral is horizontal. On polarized outlets the neutral is always the wider prong.
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Another case of backward thinking. The neutral wire can't possibly carry more current than the live wire and at the junction box, the net current should be zero if the loads are balanced.
 
psionl0 said:
Another case of backward thinking. The neutral wire can't possibly carry more current than the live wire and at the junction box, the net current should be zero if the loads are balanced.
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It does seem backwards, but in a two wire system, although the potential to ground is zero from the neutral, and though it's grounded and currentless at the breaker box, it's carrying load between breaker box and appliance. It's one reason that proper installations these days include both a neutral and a ground wire, even though they are at the same potential, and why it's against code to wire the ground and neutral terminals together on an outlet. The neutral carries current, but the ground (we hope) does not.

Why the wide terminal is neutral is a bit of a mystery, and it may just be an arbitrary choice that stuck, but I speculate that, especially in the older two wire polarized system, where there is no separate ground, it was thought safer to give the neutral higher ampacity, and a more foolproof connection, than the hot, as a neutral failure would be more deadly. Remember too that the original polarized outlet and plug system was shared by both AC and DC. But I would not be surprised to find that the real reason is that Thomas Edison flipped a coin.
 
Most if not all plugs and sockets were developed before RCD breakers became available: fuse wire and cartridge fuses were used back then.

RCD breakers have made things safer. Maybe the USA would have adopted higher voltages if RCDs had been available many years earlier.

In general, higher working voltages are better, providing that the risk of electrocution can be kept acceptably low,
 
bruto said:
It does seem backwards, but in a two wire system, although the potential to ground is zero from the neutral, and though it's grounded and currentless at the breaker box, it's carrying load between breaker box and appliance. It's one reason that proper installations these days include both a neutral and a ground wire, even though they are at the same potential, and why it's against code to wire the ground and neutral terminals together on an outlet. The neutral carries current, but the ground (we hope) does not.

Why the wide terminal is neutral is a bit of a mystery, and it may just be an arbitrary choice that stuck, but I speculate that, especially in the older two wire polarized system, where there is no separate ground, it was thought safer to give the neutral higher ampacity, and a more foolproof connection, than the hot, as a neutral failure would be more deadly. Remember too that the original polarized outlet and plug system was shared by both AC and DC. But I would not be surprised to find that the real reason is that Thomas Edison flipped a coin.
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Or simply so the neutral can't under any circumstances be shoved into the wrong hole. UK earth pins are bigger, even if someone uses a broken up or dismantled plug (some designs allow the pins to be removed) they can't push the earth pin into the live hole and (for example) make a metal external casing live. Of course they could misswire the plug but that's a seperate issue. It's also worth considering that where electrical devices are connected, deliberately such as amplifiers, or through faults or errors, that may be on separate power supplies, it is conceivable that a fault could lead to more current needing to be discharged to earth than is being supplied through a single live pin.
 
P.J. Denyer said:
Or simply so the neutral can't under any circumstances be shoved into the wrong hole. UK earth pins are bigger, even if someone uses a broken up or dismantled plug (some designs allow the pins to be removed) they can't push the earth pin into the live hole and (for example) make a metal external casing live. Of course they could misswire the plug but that's a seperate issue. It's also worth considering that where electrical devices are connected, deliberately such as amplifiers, or through faults or errors, that may be on separate power supplies, it is conceivable that a fault could lead to more current needing to be discharged to earth than is being supplied through a single live pin.
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I suppose now that you put it that way, it makes sense. If you put the hot pin to ground, you might get an instant short, spark, and blown fuse. But if you reverse and put the ground to hot, the results are less immediate and more deadly.

It's not that hard to get some two-wire polarized devices plugged together wrong. Old TV's and radios with common ground chassis were pretty easy, and the result could be a nasty jolt or worse.
 
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BowlOfRed said:
From the shared 110/220 outlet idea, I had never seen one of these before, but it's a dual outlet with one side 110 (nema5) and one side 220 (nema6). https://www.leviton.com/en/products/5844

So some folks do use things like this (with the hit to wiring cost), but you can use standard 220 plugs in it.
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An interesting idea. I don't see it having a lot of use in domestic applications unless they start making more 240 volt appliances, but I wouldn't mind a couple of those in my shop.

If you're currently having to run two sets of wire, one for 240 and one for 120, going to a single three-wire plus ground would end up as a saving.
 
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