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Thread: Definition of Feeder

  1. #21
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    Quote Originally Posted by Dennis Alwon View Post
    Yes but the proposal has an exception when there is an overcurrent protective device in between the load center and a piece of equipment only then I want that normally called feeder to be called a branch circuit. Thus the entire run between a panel and a single piece of equipment is a branch circuit whether there is a disconnect with overcurrent protective device in it or not
    what is the benefit of doing so?
    Bob

  2. #22
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    Quote Originally Posted by al hildenbrand View Post
    The conductors coming to the work bench SSU, when fused, are Feeder conductors. The conductors between the fuse LOAD side terminal and the Outlet are the Branch Circuit. The SSU is the "final OCPD."
    I can go along with that.
    Cheers and Stay Safe,

    Marky the Sparky

  3. #23
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    Quote Originally Posted by petersonra View Post
    what is the benefit of doing so?

    I believe here is the issue. 430.62 speaks of feeder for fixed motor load(s). This states that a feeder should be based on the largest overcurrent protective device for a motor plus the sum of other motors. We have only one motor so a 3 phase 20 hp motor @ 208 volts is 59.4 amps. Table 430.52 tells us to take 250% of the load for a polyphase inverse time breaker-- 148.5 amps

    This means the feeder technically should be 148.5 amps instead of a conductor size for the branch circuit at 125% 74.25 amps



    430.62 Rating or Setting — Motor Load.
    (A) Specific Load. A feeder supplying a specific fixed motor
    load(s) and consisting of conductor sizes based on 430.24 shall
    be provided with a protective device having a rating or setting
    not greater than the largest rating or setting of the branch circuit
    short-circuit and ground-fault protective device for any
    motor supplied by the feeder [based on the maximum permitted
    value for the specific type of a protective device in accordance
    with 430.52, or 440.22(A) for hermetic refrigerant motorcompressors],
    plus the sum of the full-load currents of the
    other motors of the group
    They say I shot a man named Gray and took his wife to Italy
    She inherited a million bucks and when she died it came to me
    I can't help it if I'm lucky



  4. #24
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    Maybe article 430.62 should be changed????
    They say I shot a man named Gray and took his wife to Italy
    She inherited a million bucks and when she died it came to me
    I can't help it if I'm lucky



  5. #25
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    430.62 only allows you to increase the size of the feeder OCPD above what the ampacity of the feeder conductors might otherwise limit you to. It is not the minimum rating of the feeder OCPD.
    Bob

  6. #26
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    Quote Originally Posted by petersonra View Post
    430.62 only allows you to increase the size of the feeder OCPD above what the ampacity of the feeder conductors might otherwise limit you to. It is not the minimum rating of the feeder OCPD.

    I believe it is--- read it again it states the max size of the short circuit , ground fault protective device
    They say I shot a man named Gray and took his wife to Italy
    She inherited a million bucks and when she died it came to me
    I can't help it if I'm lucky



  7. #27
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    Quote Originally Posted by Dennis Alwon View Post
    I believe it is--- read it again it states the max size of the short circuit , ground fault protective device
    430.62 Rating or Setting — Motor Load.
    (A) Specific Load. A feeder supplying a specific fixed motor
    load(s) and consisting of conductor sizes based on 430.24 shall
    be provided with a protective device having a rating or setting
    not greater than the largest rating or setting of the branch circuit
    short-circuit and ground-fault protective device for any
    motor supplied by the feeder [based on the maximum permitted
    value for the specific type of a protective device in accordance
    with 430.52, or 440.22(A) for hermetic refrigerant motorcompressors],
    plus the sum of the full-load currents of the
    other motors of the group
    It does not seem to say what you think it says. "Not greater than" means a maximum upper limit is set, but it does not affect how low the rating can go.

    All the "maximum permitted value" language does is allow you to apply the maximum allowed rating to the calculation as opposed to the rating of the actual OCPD used. It does not set a floor, but a ceiling.
    Bob

  8. #28
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    The examples on test materials say exactly what I think it says
    They say I shot a man named Gray and took his wife to Italy
    She inherited a million bucks and when she died it came to me
    I can't help it if I'm lucky



  9. #29
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    Quote Originally Posted by Dennis Alwon View Post
    Maybe article 430.62 should be changed????
    430.62 regulates "Part V. Motor Feeder Short-Circuit and Ground-Fault Protection."

    430.62 directs you to 430.24 to size the conductors. That's in Part II.
    Another Al in Minnesota

  10. #30
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    Quote Originally Posted by al hildenbrand View Post
    430.62 regulates "Part V. Motor Feeder Short-Circuit and Ground-Fault Protection."

    430.62 directs you to 430.24 to size the conductors. That's in Part II.
    If the wire between the panel and the disconnect is a feeder then that wire must be sized to the overcurrent protective device....NO? The branch circuit is sized per the motor
    They say I shot a man named Gray and took his wife to Italy
    She inherited a million bucks and when she died it came to me
    I can't help it if I'm lucky



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