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I’m aware we have 240V outlets. They are just not used in a place where you would put a PC. Until there is a shift in need (I.e., every normal user would need more than a 120V plug could handle), you won’t ever see 240V outlets in offices. I suspect it will never happen.

In server areas and extremely specialized stuff? Yea, sure. But we’re talking desktop PCs here.



There's also 20 amp circuits which are common.

Many houses run circuits that are rated for 20 amps even if they don't have the right outlet for it so this is an inexpensive upgrade for most.


I did not realize the outlet impacts the amperage… Is it a rating issue, or is there an actual part there that will trip?


Retired electrician's comments:

Most of the US utilizes the NEC for installation compliance. Per NEC, 15A-style outlets are "to code" on 20A circuits unless a single recepticle ("dedicated") circuit — in which case a 20A-style recepticle MUST be installed.

For any electric appliance (including computers) which operates for 3hrs+ ("continuously"), the circuit rating is reduced to 80% capacity (e.g. only 16A load allowed continuously on a "20A circuit" == only 1920W computers allowed on 20A circuit, 1440W on 12A).

Pro tip: check your own PSU, but practically all modern computers can handle AC input 100-240V (all you need is the correct IEC power cord for a 240 US plug).

I have fixed enough melted devices in my career to always twice-torque each&every connection I make. For temporary extension cords/plugs, "twist lock" ends are worth all the extra dollars.

Protips: use Eeez-Ox (a conductive paste which inhibits corrosion) for high-load applications (non-data, only). My own gamerig's AMD GPU has it (sparingly applied) within its dual 8-pin connectors. I supply the 8-pin connectors from a single pair of 8awg copper, which is directly soldered within the PSU's PCB power-take-offs... so only a few inches of 16awg for voltage drop (into the GPU), which reduces the amperage required (but is also unnecessary overkill).


> For any electric appliance (including computers) which operates for 3hrs+ ("continuously"), the circuit rating is reduced to 80% capacity

That's a new one for me. Do you have a reference for that? I'd love to read more.


NEC§210.20(A) a/k/a "80% Load Rule"

As trade practice, certain applications are ALWAYS deemed "continuous," e.g. water heaters, computers, space heaters, general lighting.


It’s the whole chain - 20a outlets typically require 12ga wire instead of 14ga, a 20 amp breaker, and yes - the outlet is different. The 20a outlets add a horizontal opening to one of the 2 vertical slots, making a sideways T shape. Devices that require 20 amps will have one of those horizontal prongs to ensure you don’t plug them in to a 15 amp outlet.


The outlet itself doesn't care, but the shape of the receptacle is supposed to restrict insertion of a 20 amp device into a 15 amp socket. You can stick a 15 amp device into a 20 amp socket, but not vice versa. The electrician should be installing 20 amp sockets if the cabling can support it, but many don't.

It's the difference between NEMA 5-15 and 5-20: https://en.wikipedia.org/wiki/NEMA_connector#NEMA_5


> The electrician should be installing 20 amp sockets if the cabling can support it, but many don't.

I think this is mainly because the 20 amp outlets are kind of ugly, and the fact that barely anything actually uses a 20 amp plug.

In my house, almost every circuit has a 20 amp breaker and 12 ga (yellow) romex, but only a couple of outlets are 5-20.


20a outlets are also expensive compared to 15A ones. When redoing the electrical in the house I inherited I put a dedicated circuit in the living room for the TV/game consoles/etc since my daughter's gaming rig would be going in the living room as well; since I hadn't decided to put the recessed panel for the TV wiring in at the time it was the only outlet on the circuit and code dictates that a 20A circuit with a single outlet must use a 20A receptacle.

I can buy a 10-pack of nice 15A Leviton Decora Edge outlets (that use lever lock connectors instead of screw terminals) for $26 ($2.60 each), but basic 20A tamper resistant outlets (which newer editions of the NEC require anywhere a small child can access them) are $6+ a pop.

When nothing outside of my electrical room (where the servers live) has need of a 20A receptacle it's kind of pointless to spend the extra money on them, but the extra couple bucks on 12 gauge copper is always wise.


It has long been my understanding that a single regular, bog-standard 15A duplex (ie, dual outlet) receptacle meets the multi-receptacle requirement of a 20-amp branch circuit.

If my understanding is correct, then you overkilled it and you could have saved a few dollars, at least one welli-intentioned rant, and still have been compliant with NEC.

A literally-single 15A outlet like a Leviton 16251-W would not pass muster, while one dual-outlet example of the 15-amp lever-lock devices you mention would.


Well, the rant still applies either way - the 20A outlets are 2x the cost, that's the big reason why the aren't routinely installed. I was thinking when I embarked on the project "oh, I'll just put 20A ones everywhere because why not?" and immediately decided not to when I looked at the prices for the packs of outlets....


Oh, for sure.

I had the luxury (or curse, depending) once of owning a home that needed all of the wiring replaced.

Being the kind of person that I am, I overbuilt things as I felt was appropriate. As part of that, I certainly wanted to install 20 amp outlets (even though I've never held in my hand a 20 amp plug).

The cost of that, vs good spec-grade 15A duplex outlets, was insane.

I know that the only difference is using one T-shaped contact instead of a straight and some different molds for the plastics. The line producing T-shaped contacts already exists, and so do the molds. Every 15A outlet sold today can transfer 20A safely.

It should be pennies difference in cost, and it was instead whole dollars.

Sucks.

(I'm reasonably certain that we are going to be broadly stuck with this low-current, low-voltage business until something very different comes along, and that any of this is unlikely to change in my lifetime.)


NEMA 5-20 is only required for commercial. You can use NEMA 5-15 on a 20A circuit for residential in the US.


When I said "should", I didn't mean code required it, but that slapping a 15 amp cover over a 20 amp capable circuit is kindof stupid.


If the cheaper 14guage wire was used in the walls then only the 15 amp socket is appropriate, otherwise you might plug in a 20amp device and melt the wires or burn down the house.


Not really. 15A receptacles are required by code to be able to handle 20A of current at their terminals, so the larger wire and breaker allows for more loads to be run instead of one big load to draw it all (and if you need that, then a 20A circuit with a single receptacle does actually require it to be a 20A receptacle).


>The electrician should be installing 20 amp sockets if the cabling can support it, but many don't.

Electricians will almost always install 20 amp sockets where they can, but they avoid running 12 gauge wire because it costs about 50% more.


The shape of the outlet is different for different current allowances (the spades are wider or rotated). It is supposed to allow an electrician to indicate that the whole circuit is rated to handle the higher expected load, and that there aren’t other outlets on the same circuit which might also try to use the whole current available. Basically a UI problem trying to encourage robust designs for use by non-experts


I envy my European friends' 240v electric kettles


British kettles draw so much power, the electric utility had to consider the additional power draw on the grid from synchronized tea-making during the commercial breaks of a popular soap opera, back when broadcast TV was king.


And to drive that point home, we get induction stoves that run on three-phase 400V.


D':


It is odd that having 240VAC outlets installed in kitchens for kettles has not caught on. A NEMA 6-15R would allow for parity.


> I envy my European friends' 240v electric kettles

... do you not have electric kettles in the US? Foolishly, I thought this was a standard kitchen appliance all over the world, I've even seen it in smaller cities in Peru.


We do. Like others have said, they're unusual here -- in part, because culturally we drink a lot more coffee than we do tea, but also because heating a large-ish volume of water with a normal American outlet takes awhile.

My solution to drinking a cup of tea is also unusual: I have a no-longer-in-production Sunbeam Hotshot and I use it heat only as much water as I need right now.

It raises one tea-cup worth of water from whatever temperature it is that comes out of the cold tap to boiling in about 40 seconds.

I just dump a cup of water in, push one button to heat it up, wait until it boils, and then push another button to dispense that hot liquid into the cup that I'm using for tea.

It then turns itself off until next time.


We do, but they’re limited to much lower wattage due to the outlet limits. A typical US kettle is 1100-1400W, and takes maybe 1-2 minutes to boil. Kettles in the UK are typically 2.5-3kW.



And they're probably not real. Take look at any of the clones of the dyson hair dryer and check their proclaimed RPMs, many of them would have the tip of the fan blade spinning at several mach if they actually hit their limit.

There's aquarium heaters on amazon that say they're 10kw or more and plug into a 120 outlet.

I bought a magnet that is supposed to hold "150 pounds", but pulls off the ceiling (in it's strongest position) with just 10-15 pounds.

Amazon specs are fake.


The Ninja one and probably the Breville ones will be accurate - I have the same Ninja kettle here in the UK and its 3000Watts vs the US 1500Watts.


What's your point? There's likely a few 1800W kettles that exist too. They are not common, and you definitely will never see anything above 1800W (outside of maybe some specialized commercial product designed for an 20A outlet) in the US. A 'normal' average kettle is going to be ~1200W here. Kettles start at 2kW and go up from there in the UK.


We don't have a need for an exclusive water boiling device as we aren't obsessed with tea. Most people drink coffee and the heating element is already built into the coffee maker. Idk what else you'd use it for. The stove works fine for boiling water without needing a separate appliance.


They’re far faster than a stovetop most of the time, have auto shutoff so you can wander away for a minute or two or not pay attention to it and not boil off a lot of water, etc.

Many parts of the world, it’s a good idea to boil water before using it for drinking, brushing teeth, etc.

So it’s actually really convenient for many use cases besides tea or coffee.


That's fine, but there are no use cases in the US. If we are boiling water, it's for food, and we're doing it on the stove, just like the way everyone else cooks. In the US, there is no use case for a specialized water boiling appliance.


We can agree they're less common than the UK, but saying they have "no use case" is a gross exaggeration. Pretty much everyone I know owns a kettle, given how cheap they are (~$15-20 for an OK one). Great for hot chocolate, coffee, tea, boiling water for a pot of water (to speed it up vs heating up your entire house), and numerous other reasons.


I have been known to heat water in a microwave after doing the calculations needed to know roughly when the water would reach boiling. It is rather quick once the microwave timer starts going.


There are plenty of use cases in America, and electric kettles are not uncommon here, even if they are less common than in the UK.


I use it to make oatmeal in the morning. Fastest and easiest option.


They’re readily available, but most households don't actually have one. Many more households have a coffee maker, which is essentially the same thing but specialized for dripping the boiling water through coffee grounds. Anyone else who needs boiling water just puts a pot on the stove, or possibly an old–fashioned metal tea kettle.

We could even use 240v electric tea kettles here in the US if we wanted to; most kitchens with an electric range and oven have 240v (or 208v) outlets to plug them in to. But those outlets are usually inconveniently located for counter–top appliances. It wouldn’t cost much to add another above the counter, but it is rarely done in practice. Of course, in many parts of the US natural gas heating is cheaper than electric so the houses there are built for gas ranges and ovens instead.




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