The US electrical system

[Homer J Simpson]

From Technology Connections   https://www.youtube.com/channel/UCy0tKL1T7wFoYcxCe0xjN6Q/videos


I liked the ending the best.

[Tony_G]

Thanks for sharing - I think he does a good job generally on these.

That said, as an Australian living in the US for 25 odd years, I still miss having a switch on the socket...

TonyG

[GlennSprigg]

Wow!!!  As an Aussie, I was blown away by this....  EVERYONE including outside of the U.S.
should look at this video!  I always wondered how/if in Australia we have a heater, or clothes
drier or air-cond, running on 240v and drawing 15A, then on 120v in the U.S. then it must be
drawing 30-Amps!!?? That never sounded right??

And yes, outlets without 'Switches'??  Why??

[joseph nicholas]

The US system in not just US.  Its North American, including Canada and Mexico.

[ciccio]

I'm shocked by the 200 Amps main breaker.  Here in Italy a standard family has a 3.0 to 5.5 kVA contract, which means a 16 or 20  Amp breaker.
The new meters (the ones that allow for remote reading) are programmed for a maximum load of 3.3 kVA continous (in my case, with a 3.0 kVA contract) and it will trip if you drain more than the max for a long time (minutes?).
A contract with larger limits has higher costs.
I understand the US electric supply does not discourage customers from using a lot of energy (as long as they pay the bills), but in Europe a limited amouut of current to the users side allows for better planning of the network.

[ciccio]

I always wondered how/if in Australia we have a heater, or clothes
drier or air-cond, running on 240v and drawing 15A, then on 120v in the U.S. then it must be
drawing 30-Amps!!?? That never sounded right??

And yes, outlets without 'Switches'??  Why??

If you are in the US and  you have an heater in a room, (e-g- an electric stove), it will be powered via a ridicolus plug at 120 V. The plug will overheat and a fire will start, in the standard US home built with wood.
When I was in Seattle 20 years ago, I noticed a lot of firetrucks passing by, a lot more than was usual in Europe.
My US friend said: it's normal, Christmas is coming...

[themadhippy]

a maximum load of 3.3 kVA

What? my kettle nearly uses that paltry limit  up,i'd be buggered if i wanted toast with me coffee.

[duak]

I have a 230 V kettle that I use in the workshop.  It's not instant but the waiting time is shorter - No low torque water heating for me!  It's a Tefal and uses the same 120 V base as its domestic brethren.  I imagine a 120 V unit would incinerate its heating element on 230 V.

[Bassman59]

I'm shocked by the 200 Amps main breaker.  Here in Italy a standard family has a 3.0 to 5.5 kVA contract, which means a 16 or 20  Amp breaker.

The main breaker is right after the meter, and its outputs feed the two phases (the vertical bus bars). Each individual circuit has its own breaker. It's common to see a 50 A 240 V circuit for air conditioning, a 30 A 240 circuit for an electric dryer (and yes, I'd prefer a gas dryer which is cheaper to run, but the cost of bringing the gas line to my laundry room exceeds any savings I'd get ever), and a bunch of 15 A or 20 A 120 V circuits for various household use. Yes, I just described my house.

It used to be common to pull the meter to kill power to the entire house, but now the meters are locked down by the utility. The main breaker is the only way to de-energize the panel so you can work on it.

The new meters (the ones that allow for remote reading) are programmed for a maximum load of 3.3 kVA continous (in my case, with a 3.0 kVA contract) and it will trip if you drain more than the max for a long time (minutes?).
A contract with larger limits has higher costs.
I understand the US electric supply does not discourage customers from using a lot of energy (as long as they pay the bills), but in Europe a limited amouut of current to the users side allows for better planning of the network.

The idea that the utility can control your total draw and cut you off if you exceed some limit is a complete non-starter here. And for the most part, that sort of micromanaging the grid isn't really necessary. We have "tiered" pricing as a means of discouraging excessive use, so that up to some amount of usage you pay one price per kHh, above that to the next level you pay a higher price, and above that you get fucked.

In extreme cases, like in the deep summer where air conditioning puts significant loads on the entire grid, if the utilities cannot generate or bring in the necessary power, they will institute rolling blackouts. Customers are told that power will be off for some time and to plan for that outage.

[Monkeh]

The idea that the utility can control your total draw and cut you off if you exceed some limit is a complete non-starter here.

So that's why you have no fuses. There I was thinking it was just old infrastructure you refuse to improve.

[joseph nicholas]

Here we go again.  In all of North America, the newest utility meters can turn off the power to your house without even going outside the main power station, its all done remotely.  If the cops want to get you off guard to invade your home, all they need to do is cut the power to your house and you will come outside to see what the fuck is happening.  Gotcha, without every getting their hands dirty.  It's your world, more ways to have your liberties die.

[rstofer]

I always wondered how/if in Australia we have a heater, or clothes
drier or air-cond, running on 240v and drawing 15A, then on 120v in the U.S. then it must be
drawing 30-Amps!!?? That never sounded right??

And yes, outlets without 'Switches'??  Why??

If you are in the US and  you have an heater in a room, (e-g- an electric stove), it will be powered via a ridicolus plug at 120 V. The plug will overheat and a fire will start, in the standard US home built with wood.
When I was in Seattle 20 years ago, I noticed a lot of firetrucks passing by, a lot more than was usual in Europe.
My US friend said: it's normal, Christmas is coming...

That is just wrong!  I can't even imagine an oven or stove top that isn't running on 240V.  A typical stove top might have 2 ea 3kW heaters and 2 ea 1kW heater for a total of 8kW, probably more.  This would take at least 33 Amps at 240V and the typical circuit is probably 50A.  Based on 80% usage of circuit breaker ratings, a 40A circuit would be too small so it's usually 50A.  The clothes dryer is probably 30A at 240V.  Well pump, pool filter, HVAC also run on 240V.  I'm not talking about window mounted AC units, I'm talking central air and perhaps a 3200 square foot house.

Throw in a 1200W microwave, a 5 kW air conditioner, maybe a few kW for an arc welder plus, of course, the automotive EV charger and 20 kW wouldn't be a surprise.  That's the reason most service panels are 200A.  For a single family dwelling, 100A might prove to be too small.  I know I missed (or misstated) some of the loads.  It's a fact that people used to have me replace their 100A panels with 200A.  I didn't like doing residential work but sometimes the people were friends of friends, that kind of thing.

ETA:  I forgot to add in another 5kW for the oven!

The reason that the European countries have such low demand limits (the US has none, I have installed 400A residential panels) is that the system is underbuilt.  What's a 'contract'.  We connect to the utility (actually, they connect to us) and we use whatever we want.  If our load is too high, and there is some legitimate reason, they will simply run a bigger drop and probably install a bigger transformer.  They're in the business of selling electricity, not telling their customers that they buy too much.


When I had solar power (different house) an 8 kW array provided all the energy we needed.  At the end of the year (known as settle-up), I owed the utility nothing for electricity other than a non-negotiable meter charge of $5/month.  It's pretty clear that we exceeded 8 kW during the heat of the day but it all averaged out.

[themadhippy]

In all of North America, the newest utility meters can turn off the power to your house without even going outside the main power station

Not just limited to  america,but anywhere were smart meters are installed.However that aint the worst aspect of smart meters,with them the utility providers are now able to measure your  power factor and charge accordingly

clothes dryer is probably 30A at 240V.

7kw to dry yer clothes, aint you guys heard of washing lines

[rstofer]

In all of North America, the newest utility meters can turn off the power to your house without even going outside the main power station

Not just limited to  america,but anywhere were smart meters are installed.However that aint the worst aspect of smart meters,with them the utility providers are now able to measure your  power factor and charge accordingly.

But they're not doing it anywhere I have ever heard of.  More popular is Time of Use billing and, around here, that is pretty much a dead issue.  Individual customers can subscribe to that type of billing if it suits them, the rest of us just kiss it off.

[Monkeh]

I always wondered how/if in Australia we have a heater, or clothes
drier or air-cond, running on 240v and drawing 15A, then on 120v in the U.S. then it must be
drawing 30-Amps!!?? That never sounded right??

And yes, outlets without 'Switches'??  Why??

If you are in the US and  you have an heater in a room, (e-g- an electric stove), it will be powered via a ridicolus plug at 120 V. The plug will overheat and a fire will start, in the standard US home built with wood.
When I was in Seattle 20 years ago, I noticed a lot of firetrucks passing by, a lot more than was usual in Europe.
My US friend said: it's normal, Christmas is coming...

That is just wrong!  I can't even imagine an oven or stove top that isn't running on 240V.  A typical stove top might have 2 ea 3kW heaters and 2 ea 1kW heater for a total of 8kW, probably more.  This would take at least 33 Amps at 240V and the typical circuit is probably 50A.  Based on 80% usage of circuit breaker ratings, a 40A circuit would be too small so it's usually 50A.  The clothes dryer is probably 30A at 240V.  Well pump, pool filter, HVAC also run on 240V.  I'm not talking about window mounted AC units, I'm talking central air and perhaps a 3200 square foot house.

stove, noun, "A heater, a closed apparatus to burn fuel for the warming of a room."

Not a great leap to realise he's not talking about your kitchen stove.

The reason that the European countries have such low demand limits (the US has none, I have installed 400A residential panels) is that the system is underbuilt.  What's a 'contract'.  We connect to the utility (actually, they connect to us) and we use whatever we want.  If our load is too high, and there is some legitimate reason, they will simply run a bigger drop and probably install a bigger transformer.  They're in the business of selling electricity, not telling their customers that they buy too much.

Well, see, you pay for the provision and connection of a service capable of a particular load, and that's what you receive. If you want bigger, uhm, you'll have to pay for it.

contract, noun, "An agreement between two or more parties, to perform a specific job or work order, often temporary or of fixed duration and usually governed by a written agreement."

[alpher]

Here we go again.  In all of North America, the newest utility meters can turn off the power to your house without even going outside the main power station, its all done remotely.  If the cops want to get you off guard to invade your home, all they need to do is cut the power to your house and you will come outside to see what the fuck is happening.  Gotcha, without every getting their hands dirty.  It's your world, more ways to have your liberties die.

 
Have you ever been to this side of the pond?

[WattsThat]

In general, only commercial/industrial customers pay power factor penalties in the US. As for the time of use, you can still get off-peak metering for heating swimming pools and other high kw usages at reduced rates.

The earlier comment about being out of power with the kettle on and not being able to make toast reminded me of the “ten second toast” video.

[themadhippy]

More popular is Time of Use billing and, around here, that is pretty much a dead issue.

we've economy 7 or whatever its called these days,originally meant for night storage heaters ,charge them up with cheap off peak electricity during the night then hope theirs enough energy stored to keep the house warm during the day.Originally it was a separate meter and fuse board so only the heaters were supplied by off peak but now its all done with 1 meter and the whole installation is charged at the lower rated during off peak hours,if your nocternal it can save  you a few quid,the downside is the peak  rate is slightly more than the standard tariff

[bdunham7]

 (the US has none, I have installed 400A residential panels)

I doubt those McMansions ever actually pull that much power at once, but might one reason to get a 400A service might be to get approval for more breaker spaces?  I don't know if the code limits subpanels, but my 200A service is maxed out on breakers even with a 12-space subpanel and separate panels for the solar and the pool stuff.  If it wasn't for tandem breakers, I'd be screwed.  And yet there's almost no way to get my max current over 100A, even if I run the AC, charge the car and bake a cake all at once.

[rstofer]

We do have 120/240V single phase in the US.  Other countries have 240/415V three phase or perhaps the house doesn't get 3 phase, just 240V single phase.  I don't see why the video author is so amazed, it's been this way forever!  He would be more amazed to know that we got out of the 25Hz power business just recently in New York City.  Amtrak still uses it!

Why single phase?  Well, if you use earth for the high voltage return, you can string a single wire for miles and miles through 'fly-over' country to provide power to a house where the nearest neighbor is miles away!  You can still see poles with a single insulator and just a single conductor.

This arrangement is known as SWER - Single Wire Earth Return
https://en.wikipedia.org/wiki/Single-wire_earth_return

[Monkeh]

We do have 120/240V single phase in the US.  Other countries have 240/415V three phase or perhaps the house doesn't get 3 phase, just 240V single phase.  I don't see why the video author is so amazed, it's been this way forever!

.. did you watch the video at all?

[rstofer]

 (the US has none, I have installed 400A residential panels)

I doubt those McMansions ever actually pull that much power at once, but might one reason to get a 400A service might be to get approval for more breaker spaces?  I don't know if the code limits subpanels, but my 200A service is maxed out on breakers even with a 12-space subpanel and separate panels for the solar and the pool stuff.  If it wasn't for tandem breakers, I'd be screwed.  And yet there's almost no way to get my max current over 100A, even if I run the AC, charge the car and bake a cake all at once.

If they use marginally more than 200A, the next panel size is 400A and that is independent of breaker spaces. I think panels are limited to 42 circuits (poles) but you can buy 30 circuit, 24 circuit, any of a number of other sizes.

My incoming panel is 400A with just 2 pole breakers for feeders.  There is a 100A panel in the Laundry, another 100A panel in the Garage, a 50A panel in the shed and another in the Gym.  Lots and lots of 15A and 20A circuits.  We use gas for heating and the fireplace insert but the rest of the place is electric.

[rstofer]

We do have 120/240V single phase in the US.  Other countries have 240/415V three phase or perhaps the house doesn't get 3 phase, just 240V single phase.  I don't see why the video author is so amazed, it's been this way forever!

.. did you watch the video at all?

About the first exciting 30 seconds!

[Monkeh]

We do have 120/240V single phase in the US.  Other countries have 240/415V three phase or perhaps the house doesn't get 3 phase, just 240V single phase.  I don't see why the video author is so amazed, it's been this way forever!

.. did you watch the video at all?

About the first exciting 30 seconds!

Well that explains why you don't know what the video is about, doesn't it?

[duckduck]

 (the US has none, I have installed 400A residential panels)

I doubt those McMansions ever actually pull that much power at once, but might one reason to get a 400A service might be to get approval for more breaker spaces?

Just put in a bigger breaker for one breaker space and then run a sub-panel. This is sometimes done for a kitchen that is far away from the main panel, etc. It's cheaper / easier to run one big wire than a bunch of little ones.

EDIT:

I realize this doesn't directly address your question. I'm not sure how permitting is typically done for residential in the USA. It's by county and they all follow the National Electric Code (with various modifications). I assume that as long as everything meets code you can get as many amps and breakers as you can afford to install. Those damn breakers are US$50 each for modern combo GFCI/arc-flash ones (you might need 15-20 of the 20A ones) and US$1,000 for an average size residential load center / panel / breaker box. You'll be paying an electrician to do this work, too.

EDIT EDIT:

I've never heard of a power meter that can cut power by remote control until this thread. That seems a little scary to me for all kinds of reasons: fire safety, security, etc. My nest has two 120 V RMS phases that can easily supply 100 A each. That's a lot riding on a couple of switches that I can't physically inspect or secure from hackers.

EDIT EDIT EDIT:

I'm just gonna edit this post to death. I live in the Seattle metro area and I haven't noticed more house fires than when I lived in other (warmer) parts of the US.

EDIT EDIT EDIT EDIT:

Electromechanical spinning disk meter on my nest. I'm not a big fan of "smart" meters or "smart" anything else. Also, get off my lawn.