How small can my service neutral be when most of the load is 240v?

Discussion in 'Electrical Forum discussion & Blog' started by tkeoki, May 14, 2013.

  1. tkeoki

    tkeoki New Member

    Messages:
    29
    Non-residential 120/240 single phase service. 320amp meter to (2) 200 amp panels. The distance from the meter on a pole to service panels are 50ft. I'm running 3/0 copper for the phase conductors. #6 for the grounds.

    First panel will have 160 amp continuous load. Everything connected will be 240v. The second panel will have 40 amps of 120v and 120 amps of 240v.

    Even though there is no 120v equipment on the first panel, I can't go lower than the GEC, right? #6?
  2. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,529
    Location:
    North Carolina
    can't go lower than the GEC
  3. Glennsparky

    Glennsparky New Member

    Messages:
    22
    Location:
    Oviedo, FL near Orlando
    Or no neutral. There's no code forcing you to bring a neutral to a box. But, then you could never use that box for a 120v load.
  4. bluebinky

    bluebinky Member

    Messages:
    383
    Location:
    Santa Clara, CA
    I thought 3/0 copper service required #4 GEC. I'm probably reading the wrong table again, though...
  5. jwelectric

    jwelectric Electrical Contractor/Instructor

    Messages:
    2,529
    Location:
    North Carolina
    You are correct about a #4
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