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  1. #1
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    Default Panel - balanced load

    This panel was wired with all 120V breakers on a single phase. Is this a problem and if so, what is the code requirement.

    Thanks

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  2. #2
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    Default Re: Panel - balanced load

    Every other breaker is on the opposite leg of the one above or below it. Panels use an ABABA arrangement top to bottom.

    All answers based on unamended National Electrical codes.

  3. #3
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    Default Re: Panel - balanced load

    Quote Originally Posted by Ken Amelin View Post
    This panel was wired with all 120V breakers on a single phase. Is this a problem and if so, what is the code requirement. Thanks
    Jim is correct (no surprise there). If you look at the center of the panel, you will see the buss bar stubs alternate, one from the left buss bar and the next from the right. If you were to put a meter or neon tester on adjacent breaker terminals, you would get 240 volts.

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    Default Re: Panel - balanced load

    Also, balancing a single phase residential panel is an exercise in futility. The loads are transient based on the time of day as the usage moves. A 240 volt circuit is automatically balanced.

    All answers based on unamended National Electrical codes.

  5. #5
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    Default Re: Panel - balanced load

    Like this (see annotated photo).

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    Default Re: Panel - balanced load

    Quote Originally Posted by Ken Amelin View Post
    This panel was wired with all 120V breakers on a single phase. Is this a problem and if so, what is the code requirement.

    Thanks
    Ken,
    For clarity. When you said "single phase" were you meaning to say "single leg"?


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    Default Re: Panel - balanced load

    Quote Originally Posted by Garry Sorrells View Post
    Ken,
    For clarity. When you said "single phase" were you meaning to say "single leg"?
    Based on the arrangement of the breakers I assumed he meant single leg. The question really wouldn't make sense since the entire panel is single phase.

    All answers based on unamended National Electrical codes.

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    Default Re: Panel - balanced load

    Quote Originally Posted by Jim Port View Post
    Based on the arrangement of the breakers I assumed he meant single leg. The question really wouldn't make sense since the entire panel is single phase.
    I was thinking the panel was 2phase? (2 - 120V conductors?)

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    Default Re: Panel - balanced load

    A 120/240 residential service is single phase. Commercial electric will be three phase. Two phase is not used.

    All answers based on unamended National Electrical codes.

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    Default Re: Panel - balanced load

    Quote Originally Posted by Ken Amelin View Post
    I was thinking the panel was 2phase? (2 - 120V conductors?)
    Ken,

    The confusion may come from that there are two phase conductors, 240 volts between them with a tap off the center to create 120 volts between each phase conductor and the neutral tap conductor.

    Single phase, two ungrounded phase conductors with one grounded neutral conductor.

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    Default Re: Panel - balanced load

    Ken, I thought you were heading down the path of 2 legs means 2 phase. There is a difference between 1, 2 and 3 phase and there preferred applications. I do not know who still may supplying 2 phase, though there is some reference to a couple of locations in the US.

    I am not sure how to truly simplify the explanation of 2 phase and 3 phase, maybe some one else might make an attempt. Basically it primarily revolves around motors and cable size.

    Here is a link to understanding the application.

    Major difference between a 2-phase and a 3-phase stator

    Major difference between a 2-phase and 3-phase stator? | EEP


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    Default Re: Panel - balanced load

    Quote Originally Posted by Ken Amelin View Post
    This panel was wired with all 120V breakers on a single phase. Is this a problem and if so, what is the code requirement.

    Thanks
    How many 120 amp breakers?
    What does the panel legend say?
    From what I understand without going in code, Jerry will be more helpful, a main panel can be used as a source to provide 6 remote panels.

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    Default Re: Panel - balanced load

    Quote Originally Posted by ROBERT YOUNG View Post
    From what I understand without going in code, Jerry will be more helpful, a main panel can be used as a source to provide 6 remote panels.
    One could start with one service equipment panel with one main service disconnect (and there could be up to six service disconnects), and that one service equipment panel could feed as many remote panels as there are circuits in that panel.

    The limiting factor is the rating of the service disconnect, which needs to be the same as, or less than, the rating of the service entrance conductors and the rating of the bus in the service equipment panel.

    One could have a 100 amp service equipment panel feeding a 400 amp remote panel ... it would be a waste of money because the most that will be available to that 400 amp remote panel is 100 amps through the service equipment panel.

    That would be like trying to feed a 2" fire hose from a 1/2" garden hose ...

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    Default Re: Panel - balanced load

    Quote Originally Posted by Jerry Peck View Post
    One could start with one service equipment panel with one main service disconnect (and there could be up to six service disconnects), and that one service equipment panel could feed as many remote panels as there are circuits in that panel.

    The limiting factor is the rating of the service disconnect, which needs to be the same as, or less than, the rating of the service entrance conductors and the rating of the bus in the service equipment panel.

    One could have a 100 amp service equipment panel feeding a 400 amp remote panel ... it would be a waste of money because the most that will be available to that 400 amp remote panel is 100 amps through the service equipment panel.

    That would be like trying to feed a 2" fire hose from a 1/2" garden hose ...
    Ha ha ha. Or a two pound salami in a an 8 pound rated paper bag.
    Good point.

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    Default Re: Panel - balanced load

    Quote Originally Posted by Ken Amelin View Post
    This panel was wired with all 120V breakers on a single phase. Is this a problem and if so, what is the code requirement.

    Thanks
    Quote Originally Posted by Ken Amelin View Post
    I was thinking the panel was 2phase? (2 - 120V conductors?)
    Quote Originally Posted by ROBERT YOUNG View Post
    How many 120 amp breakers?
    What does the panel legend say?
    From what I understand without going in code, Jerry will be more helpful, a main panel can be used as a source to provide 6 remote panels.


    Like many things it is the meaning of the words that make true understanding.

    Single phase and 2 or 3 phase are specific things.
    Legs don't make up, under normal residential use, Phases.
    Ken says that he is looking at 120 v breakers.
    It may be that Ken has confusion over how the breakers are actually balanced between the two legs not realizing that the breakers alternate between the two legs on one side of the panel.
    Which takes us back to the words used and what he was trying to say. I and others may understand what he meant and what was the real question question, but others may not, so it is always better to correct the question so that the words are in proper use and context.

    ROBERT,,, We nee to read a bit slower and take time to comprehend what is being said. Ken was talking about 120v not 120amp breakers. You take the original question and have morphed it into something entirely different and into a different topic all together.

    Read a bit slower...

    PS.: HAPPY LABOR DAY TO ALL ! ! !

    Last edited by Garry Sorrells; 09-05-2016 at 09:33 AM.

  16. #16
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    Default Re: Panel - balanced load

    The photo is a bit dark, but I noticed that the OP said it was all 120 volt breakers. I see a couple white wires connected to breakers, so it looks like there are a could 240 volt circuits. You really cannot properly inspect a panel without understanding the concept of how panels are constructed.

    Regarding phases, look up some basic electrical theory on the web. Three-phase can get complicated, but just looking at diagrams showing sine waves for single phase and three-phase can be a good visual indicator of how they work.


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    Default Re: Panel - balanced load

    Quote Originally Posted by Garry Sorrells View Post
    Like many things it is the meaning of the words that make true understanding.

    Single phase and 2 or 3 phase are specific things.
    Legs don't make up, under normal residential use, Phases.
    Ken says that he is looking at 120 v breakers.
    It may be that Ken has confusion over how the breakers are actually balanced between the two legs not realizing that the breakers alternate between the two legs on one side of the panel.
    Which takes us back to the words used and what he was trying to say. I and others may understand what he meant and what was the real question question, but others may not, so it is always better to correct the question so that the words are in proper use and context.

    ROBERT,,, We nee to read a bit slower and take time to comprehend what is being said. Ken was talking about 120v not 120amp breakers. You take the original question and have morphed it into something entirely different and into a different topic all together.

    Read a bit slower...

    PS.: HAPPY LABOR DAY TO ALL ! ! !
    I concur.
    Concentrate on the subject/topic.

    I am not a good multi-tasker.

    Happy labour day to you all.

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