1. If you enjoy the forum please consider supporting it by signing up for a NES Membership  The benefits pay for the membership many times over.

  2. Dismiss Notice

Electrical help pls, what amperage is this breaker

Discussion in 'Off-Topic' started by boatman, Feb 11, 2019.

  1. boatman

    boatman

    Joined:
    Jan 30, 2012
    Messages:
    1,438
    Likes Received:
    329
    Unsure of how breakers are notated for 240 V, this is on my water heater circuit, see position 13-15. This is a double/ganged breaker, I think this is 40A total for the 240V, and not 80 total, right? 40A on each 120, so 40 total on the 240? thanks.
     

    Attached Files:

  2. Super99Z

    Super99Z NES Member

    Joined:
    Aug 30, 2010
    Messages:
    4,046
    Likes Received:
    2,838
    Location:
    South Shore
    40
     
    TLB and Lip like this.
  3. arsco

    arsco NES Member

    Joined:
    Dec 21, 2012
    Messages:
    360
    Likes Received:
    501
    2 pole 40amp
     
    Lip likes this.
  4. n1bsbri

    n1bsbri NES Member

    Joined:
    Dec 3, 2011
    Messages:
    3,141
    Likes Received:
    779
    Location:
    RI - but not on the island part
    40 amp at 240 volts,
    2X 40 amp at 120 volts
     
    MuzzleDiscipline and Lip like this.
  5. one-eyed Jack

    one-eyed Jack Manufacturer Dealer NES Member

    Joined:
    Apr 12, 2006
    Messages:
    8,547
    Likes Received:
    8,006
    Location:
    Eastern Mass and southern NH
    That's why they put"40" on the breaker. Jack.
     
    Koolmoose, xjma99, DPR and 7 others like this.
  6. chrbla2000

    chrbla2000 NES Member

    Joined:
    Mar 24, 2012
    Messages:
    678
    Likes Received:
    339
    He was probably hoping for a 9mm or .45 breaker instead of a fo-tay.
     
    bauer, xjma99, AHM and 3 others like this.
  7. Super99Z

    Super99Z NES Member

    Joined:
    Aug 30, 2010
    Messages:
    4,046
    Likes Received:
    2,838
    Location:
    South Shore
    They really don't want consumers doing math[​IMG]
     
    slugworth, DPR, crazymjb and 4 others like this.
  8. Mark from MA

    Mark from MA NES Member

    Joined:
    Jun 4, 2008
    Messages:
    4,738
    Likes Received:
    1,391
    No one likes 40 here....even in electrical service boxes.
     
    xjma99, DPR, Dennis in MA and 3 others like this.
  9. slap shot

    slap shot NES Member

    Joined:
    Mar 5, 2013
    Messages:
    11,711
    Likes Received:
    5,462
    Location:
    NH
    which one?, the one that says 40 or the one that says 30? or the one that says 60? [rofl]

    i'm sorry, i can't help it sometimes...
     
    DPR, AHM, Uzi2 and 1 other person like this.
  10. SERE

    SERE NES Life Member NES Member

    Joined:
    Oct 30, 2010
    Messages:
    5,043
    Likes Received:
    3,341
    Location:
    North of Boston
    I was ready, too, but he had this in there:
    [angry]
     
    slap shot likes this.
  11. Mr.E

    Mr.E

    Joined:
    Mar 29, 2014
    Messages:
    2,929
    Likes Received:
    1,610
    upload_2019-2-11_15-20-57.jpeg
     
    xjma99 likes this.
  12. MisterHappy

    MisterHappy NES Member

    Joined:
    Jul 28, 2009
    Messages:
    20,124
    Likes Received:
    4,824
    Location:
    On the 16 yard line, shootin' for the Lewis!
  13. Spanz

    Spanz NES Member

    Joined:
    Feb 25, 2009
    Messages:
    28,627
    Likes Received:
    13,529
    in a 120 v system, there is a hot lead, and a return lead. In the USA the hot lead is colored black, and the return lead is white. If the white lead gets cut, and touches earth ground somewhere....nothing happens as the return lead is also at 0 volts (approximately). So in a 120V system, you only need to fuse the hot lead.

    But in a 240 V system, it is really comprised of TWO 120V circuits. I guess you can think of one as being Positive polarity, and the other negative polarity. If EITHER of these two hot leads is cut and touches earth ground, there will be a short circuit and a big arc of current forms. You do not know ahead of time if the positive lead, or the negative lead will be the one short circuiting, so you have to put a circuit breaker on BOTH hot leads. If Either of them shorts out, you want to turn off the other one, even if it is not short circuited, for safety reasons, so the two circuit breakers are ganged together with a physical bar.

    Normally current flows out of the positive lead circuit breaker, to the load, then back to the negative lead circuit breaker, completing the circuit loop. NO current should flow in the neutral wire at all. So even though there are two 40 amp circuit breakers, the actual current in the loop is only 40 amps. The same 40 amps flows thru each breaker.
     
    amb, crazymjb, alpineboard and 4 others like this.
  14. radioman

    radioman NES Member

    Joined:
    Jul 9, 2009
    Messages:
    3,736
    Likes Received:
    1,580
    Location:
    N.C.MA, NRA Life Member
    Looks like you got your answer. To simplify———
    A 240v 40a breaker is 40a total. Not 80.
     
    Uzi2 likes this.
  15. Mr. Brownstone

    Mr. Brownstone NES Member

    Joined:
    May 2, 2012
    Messages:
    3,116
    Likes Received:
    1,044
    Location:
    PRM Northshore
    Wanna really blow his mind...
     

    Attached Files:

    xjma99 and SgtHal75 like this.
  16. Winchester73

    Winchester73

    Joined:
    Dec 31, 2012
    Messages:
    776
    Likes Received:
    257
    Location:
    Nipmuc Country Until 1673
    I wired this once. The hard part was getting the Holy Water to remain Holy.
     
    xjma99, fshalor, mibro and 1 other person like this.
  17. AHM

    AHM NES Member

    Joined:
    Dec 30, 2013
    Messages:
    5,666
    Likes Received:
    2,872
    "We really try and discourage people from arithmetic".
    -- Marsha​
     
  18. Spanz

    Spanz NES Member

    Joined:
    Feb 25, 2009
    Messages:
    28,627
    Likes Received:
    13,529
    [​IMG]

    you ONLY use one of those if you need to reverse the polarity of the neutron flow
     
    Mr. Brownstone likes this.
  19. alpineboard

    alpineboard

    Joined:
    Sep 26, 2014
    Messages:
    660
    Likes Received:
    258
    Location:
    New Hampshire
  20. 1776

    1776 NES Member

    Joined:
    Mar 5, 2006
    Messages:
    3,331
    Likes Received:
    902
    Location:
    SE MA
    Test it with a wet finger. I'll have to check the book on those positions...never got that far!
     
  21. SgtHal75

    SgtHal75 NES Member

    Joined:
    Jul 10, 2016
    Messages:
    1,333
    Likes Received:
    1,210
    Location:
    Hidden rebel base
    Hahahaha!!!!!
     
    Mr. Brownstone likes this.
  22. JackOfAllTrades

    JackOfAllTrades

    Joined:
    Jul 5, 2013
    Messages:
    757
    Likes Received:
    392
    Yep... where 120+120=208.
     
    SgtHal75 and Mr. Brownstone like this.
  23. Mr. Brownstone

    Mr. Brownstone NES Member

    Joined:
    May 2, 2012
    Messages:
    3,116
    Likes Received:
    1,044
    Location:
    PRM Northshore
    And 120+120+120 = 208 as well.
     
  24. 1776

    1776 NES Member

    Joined:
    Mar 5, 2006
    Messages:
    3,331
    Likes Received:
    902
    Location:
    SE MA
    The flux converter needs to be in temporal phase
     
  25. 556USER

    556USER NES Member

    Joined:
    Dec 19, 2018
    Messages:
    279
    Likes Received:
    233
    Location:
    Northshore MA
    All the current is lagging by 90 degrees.
     
  26. one-eyed Jack

    one-eyed Jack Manufacturer Dealer NES Member

    Joined:
    Apr 12, 2006
    Messages:
    8,547
    Likes Received:
    8,006
    Location:
    Eastern Mass and southern NH
    If it runs backwards change any two wires. (3phase, that is) Jack.
     
    xjma99, RHJJ and AHM like this.
  27. 556USER

    556USER NES Member

    Joined:
    Dec 19, 2018
    Messages:
    279
    Likes Received:
    233
    Location:
    Northshore MA
    Yep 120 degree phase diff says Nikola Tesla
     
  28. 1776

    1776 NES Member

    Joined:
    Mar 5, 2006
    Messages:
    3,331
    Likes Received:
    902
    Location:
    SE MA
    I always change the outer two to reverse direction
     
  29. MisterHappy

    MisterHappy NES Member

    Joined:
    Jul 28, 2009
    Messages:
    20,124
    Likes Received:
    4,824
    Location:
    On the 16 yard line, shootin' for the Lewis!
    I would have put my money on the ee, or the warm front. [laugh]
     
  30. RHJJ

    RHJJ

    Joined:
    Oct 5, 2007
    Messages:
    15,887
    Likes Received:
    3,280
    Location:
    South Coast
    Good chance it is 40.
     

Share This Page