6 ms·

I always forget the size difference between US and UK homes (I assume toomuchtodo is speaking from a US perspective). Here, in my three-bedroom UK house I'm on

I always forget the size difference between US and UK homes (I assume toomuchtodo is speaking from a US perspective). Here, in my three-bedroom UK house I'm on a 60A service fuse and considering updating to 100A in the future (amusingly, as part of a solar PV / electric vehicle charger install). I've never heard of a UK house having a larger than 100A service (although I imagine they exist here and there - it's certainly not common).

SketchySeaBeast 4y ago
I'd never heard of a 400 A service until just this discussion (it's common to have 100 A - 200 A), but it's important to keep in mind the voltage differences and that effect on total power: UK: 100 A x 230 V = 23,00 W US: 200 A x 120 V = 24,00 W Edit: I am wrong in my understanding of US power distribution. It's 200 A per leg, which the US has two of. But it seems like the UK may or may not have 380 3 Phase, so the numbers are weird there too. Wrong all around!
- throwawayacc3 4y ago
  Voltage to residential main electrical service panels in the United States is 240V. Major appliances run on 240V circuits. So when you install a 400A panel in the US, it's 400A*240V which is 96,000W.
  - kuschku 4y ago
    And service in EU is 380V, so the relationship between the numbers remains similar.
    - throwawayacc3 4y ago
      That is incorrect. The EU/UK are on 230V at 50Hz at residential service entry.
      - kuschku 4y ago
        I'm not sure where in EU you live, but every instant water heater, stove, and many semi-professional workshop devices require 380V. At least in Germany, 380V is standard for such devices and available in every household.
        xxpor 4y ago
        3 phase vs single phase depends on which country you're in in the EU.
        rootusrootus 4y ago
        I think you might almost understand how it feels when someone makes gross generalizations across the entire US :). One thing I keep learning about the EU is ... do not generalize using Germany as the baseline. There are many areas where Germany is the odd one out, not the standard.
- sbradford26 4y ago
  Services to the US are at 240V though they just utilize a center tap transformer to allow two different 120v legs. So that 200 amp service is 200 amps at 240V so approximately 48kW. Largely US homes have bigger feeds in because the US has significantly larger homes on average and the prevalence of AC and other higher power usage devices in US homes.
- danans 4y ago
  > but it's important to keep in mind the voltage differences and that effect on total power: > UK: 100 A x 230 V = 23,00 W > US: 200 A x 120 V = 24,00 W That's incorrect. The service drop in the US is 220V. It gets stepped down at the main load center to 120V for most of the regular circuits. So it's more like 48000W service in US houses.
  - kuschku 4y ago
    The service drop in EU/UK is 380V. The point stands.
    - petre 4y ago
      400V between phases, 230V phase to neutral. Most homes have single phase though.
      - kuschku 4y ago
        So how would you run an instant water heater or electric induction stove then? Every apartment and house I've ever lived in had 380V three-phase right to the kitchen, to the bathroom, and to basement rooms (e.g. for prosumer workshop tools).
        danans 4y ago
        > So how would you run an instant water heater or electric induction stove then? Every apartment and house I've ever lived in had 380V three-phase right to the kitchen, I run an induction stove on 220V single phase every day here in the US.
        petre 4y ago
        Isn't it two phase? AFAIK in the US you have 240V two phase with 180° between them.
        4y ago
- deleted 4y ago
  [deleted]
- rsync 4y ago
  No, he's right. It's not about having 400 amps per se but about sizing the wire you put in the ground. Maybe you'll have a 200a main breaker and you'll only ever use 200 amps, etc. - but the hard part was digging and future you or other future yous will be happy that the wire was upsized when it was put in. Same with conduit. Same with number of conduits. I can't tell you how many times I have been very pleased with myself that I threw in that extra 3/4 conduit line when we dug that one trench that one time ...
cortesoft 4y ago
Isn't this because the UK standard is 230 volts? The US is only 120, so you need almost twice the amps for the same power.
- sbradford26 4y ago
  Services to the US are at 240V they just utilize a center tap transformer to allow two different 120v legs. So that 200 amp service is 200 amps at 240V so approximately 48kW.
mech987 4y ago
UK homes run on 230 volts, so each amp is worth double what US amps are worth (running on 115 volts in the US) edit: 115 volts per leg, and US has 2 legs, so it comes out in the wash, surprisingly. UK homes have tiny little service amps!
- rootusrootus 4y ago
  No. US homes run on 240V, not 120, and not 115 * 2. We provide a center-tap neutral so you can split the single phase 240V if you desire. And we do exactly that for many smaller circuits, including the majority of wall sockets.
nemo44x 4y ago
A friend of mine has 400A of service in the UK in the countryside as it's an old farmhouse and is pretty large even by USA standards.

SketchySeaBeast 4y ago

I'd never heard of a 400 A service until just this discussion (it's common to have 100 A - 200 A), but it's important to keep in mind the voltage differences and that effect on total power: UK: 100 A x 230 V = 23,00 W US: 200 A x 120 V = 24,00 W Edit: I am wrong in my understanding of US power distribution. It's 200 A per leg, which the US has two of. But it seems like the UK may or may not have 380 3 Phase, so the numbers are weird there too. Wrong all around!

throwawayacc3 4y ago
Voltage to residential main electrical service panels in the United States is 240V. Major appliances run on 240V circuits. So when you install a 400A panel in the US, it's 400A*240V which is 96,000W.
- kuschku 4y ago
  And service in EU is 380V, so the relationship between the numbers remains similar.
  - throwawayacc3 4y ago
    That is incorrect. The EU/UK are on 230V at 50Hz at residential service entry.
    - kuschku 4y ago
      I'm not sure where in EU you live, but every instant water heater, stove, and many semi-professional workshop devices require 380V. At least in Germany, 380V is standard for such devices and available in every household.
      - xxpor 4y ago
        3 phase vs single phase depends on which country you're in in the EU.
      - rootusrootus 4y ago
        I think you might almost understand how it feels when someone makes gross generalizations across the entire US :). One thing I keep learning about the EU is ... do not generalize using Germany as the baseline. There are many areas where Germany is the odd one out, not the standard.
sbradford26 4y ago
Services to the US are at 240V though they just utilize a center tap transformer to allow two different 120v legs. So that 200 amp service is 200 amps at 240V so approximately 48kW. Largely US homes have bigger feeds in because the US has significantly larger homes on average and the prevalence of AC and other higher power usage devices in US homes.
danans 4y ago
> but it's important to keep in mind the voltage differences and that effect on total power: > UK: 100 A x 230 V = 23,00 W > US: 200 A x 120 V = 24,00 W That's incorrect. The service drop in the US is 220V. It gets stepped down at the main load center to 120V for most of the regular circuits. So it's more like 48000W service in US houses.
- kuschku 4y ago
  The service drop in EU/UK is 380V. The point stands.
  - petre 4y ago
    400V between phases, 230V phase to neutral. Most homes have single phase though.
    - kuschku 4y ago
      So how would you run an instant water heater or electric induction stove then? Every apartment and house I've ever lived in had 380V three-phase right to the kitchen, to the bathroom, and to basement rooms (e.g. for prosumer workshop tools).
      - danans 4y ago
        > So how would you run an instant water heater or electric induction stove then? Every apartment and house I've ever lived in had 380V three-phase right to the kitchen, I run an induction stove on 220V single phase every day here in the US.
        petre 4y ago
        Isn't it two phase? AFAIK in the US you have 240V two phase with 180° between them.
        4y ago
deleted 4y ago
[deleted]
rsync 4y ago
No, he's right. It's not about having 400 amps per se but about sizing the wire you put in the ground. Maybe you'll have a 200a main breaker and you'll only ever use 200 amps, etc. - but the hard part was digging and future you or other future yous will be happy that the wire was upsized when it was put in. Same with conduit. Same with number of conduits. I can't tell you how many times I have been very pleased with myself that I threw in that extra 3/4 conduit line when we dug that one trench that one time ...

cortesoft 4y ago

Isn't this because the UK standard is 230 volts? The US is only 120, so you need almost twice the amps for the same power.

sbradford26 4y ago
Services to the US are at 240V they just utilize a center tap transformer to allow two different 120v legs. So that 200 amp service is 200 amps at 240V so approximately 48kW.

mech987 4y ago

UK homes run on 230 volts, so each amp is worth double what US amps are worth (running on 115 volts in the US) edit: 115 volts per leg, and US has 2 legs, so it comes out in the wash, surprisingly. UK homes have tiny little service amps!

rootusrootus 4y ago
No. US homes run on 240V, not 120, and not 115 * 2. We provide a center-tap neutral so you can split the single phase 240V if you desire. And we do exactly that for many smaller circuits, including the majority of wall sockets.

nemo44x 4y ago

A friend of mine has 400A of service in the UK in the countryside as it's an old farmhouse and is pretty large even by USA standards.