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Household Amperage

  1. Jun 3, 2010 #1
    What is the typical Amperage that comes into a normal household?
     
  2. jcsd
  3. Jun 3, 2010 #2

    stewartcs

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    Less than the service breaker rating. Most residential homes have around a 150-amp to 200-amp service. The load will depend on what is on in the house of course.

    CS
     
  4. Jun 3, 2010 #3
    Well it depends upon the supply voltage.

    What is yours?
     
  5. Jun 3, 2010 #4

    russ_watters

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    True, but AFAIK, most countries use similar supply voltages in the 220-240V range. The US uses 240V and typical amperages range from 40A for a small apartment to 200A for a medium-sized house.
     
  6. Jun 3, 2010 #5
    How many amps tipically for an Industrial 3-phase Y and Delta?
     
  7. Jun 3, 2010 #6
    Typical Amperage for 3-phase.
    Supply to Demand:

    Delta to Delta
    Deltas to Y
    Y to Delta
    Y to Y
     
  8. Jun 3, 2010 #7

    russ_watters

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    There is no "typical" for industry since industrial requirements can vary by several orders of magnitude. You could see anything up to a few thousand amps at anything up to 13,200 volts. From a few kilowatts to a few dozen megawatts.
     
  9. Jun 3, 2010 #8

    dlgoff

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    You got me curious as I was thinking about http://en.wikipedia.org/wiki/Electric_arc_furnace" [Broken].
     
    Last edited by a moderator: May 4, 2017
  10. Jun 3, 2010 #9

    Borek

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    Strange, I always thought it is 110/120V. That's why we here have problems with things bought in US.
     
  11. Jun 3, 2010 #10

    turbo

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    The US feeds street-level transformers with high line voltages, and the transformers knock the voltage down to 240V. The secondary coils are center-tapped to provide 120V to each of the two legs at the breaker panel. We only get 240V when loads are connected leg-to-leg, like electric ranges, clothes dryers, and submersible pumps.
     
  12. Jun 3, 2010 #11

    dlgoff

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    Yes 120volts would be nominal. But...
    http://en.wikipedia.org/wiki/Mains_electricity#Standardization"
     
    Last edited by a moderator: Apr 25, 2017
  13. Jun 3, 2010 #12
    In my first house (back in the 1970s) i had a problem with lights burning out very quickly. When I checked the line voltage it was 127.x VAC. When I switched to sylvania bulbs from the GE I was using they lasted almost twice as long.... all I can think is that GE specs their lights at 110 and Sylvania specs them at a higher voltage.
    It all depends on where you are on the grid as to what your actual voltage is.
     
  14. Jun 3, 2010 #13

    russ_watters

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    So that's 120V (or in special cases 240V) at the wall, but 240V at the main electrical panel. It's nice for flexibility.
     
  15. Jun 3, 2010 #14

    turbo

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    And generally topped out at 200 amps design rating at the main panel and breaker box. In the US, we generally have 15 amp breakers, and in bridged (240 V) breakers the total amperage is 30 amps.
     
  16. Jun 4, 2010 #15

    Averagesupernova

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    Care to explain that?
     
  17. Jun 4, 2010 #16

    russ_watters

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    I think he's talking about a two-pole (so 240V) breaker being 15+15=30A. If so, it isn't correct. 15A times two poles is still just 15A. Nor is the typical amperage correct. 40A breakers are pretty standard for large household devices and you'll occasionally see 60A breakers.
     
  18. Jun 4, 2010 #17
    Looking at both the OP's questions together I wonder if this is homework?
     
  19. Jun 4, 2010 #18

    russ_watters

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    Dunno. They are pretty vague for homework.
     
  20. Jun 4, 2010 #19
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