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Thread: 65 amps

  1. #1
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    65 amps

    The plans call for a 65 amp over backfeed breaker, existing 200 amp de rate main to 175, which only leaves room for 65 amp, I can't find a 65 amp breaker can I go up to the next standard size 70 amp but then I'm over the 120% thanks

  2. #2
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    Quote Originally Posted by SAP View Post
    The plans call for a 65 amp over backfeed breaker, existing 200 amp de rate main to 175, which only leaves room for 65 amp, I can't find a 65 amp breaker can I go up to the next standard size 70 amp but then I'm over the 120% thanks
    Who drew up those plans? There is no 65A breaker.

    If you are under the 2014 NEC, you use 125% of the nameplate inverter current, not the breaker rating, to make your 120% rule calculation.

  3. #3
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    Quote Originally Posted by ggunn View Post
    Who drew up those plans? There is no 65A breaker.

    If you are under the 2014 NEC, you use 125% of the nameplate inverter current, not the breaker rating, to make your 120% rule calculation.

    So the 120% rule doesn't use the panel buss rating anymore.
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  4. #4
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    Quote Originally Posted by Dennis Alwon View Post
    So the 120% rule doesn't use the panel buss rating anymore.
    705.12(D)(2)(3); case (b) is the 120% rule. The main breaker rating plus 125% of the inverter nameplate current cannot exceed 120% of the bus rating. It's the backfed breaker rating that no longer applies.

  5. #5
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    So I have two 6000 solar edge single phase inverters 25 amps 1.25 percent of each inverter is 31.25, backfeed going to main would be 62.5. If I'm reading right I can put whatever breaker in my main which in this case would be a 70 amp thank you

  6. #6
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    Quote Originally Posted by SAP View Post
    So I have two 6000 solar edge single phase inverters 25 amps 1.25 percent of each inverter is 31.25, backfeed going to main would be 62.5. If I'm reading right I can put whatever breaker in my main which in this case would be a 70 amp thank you
    You can put in any breaker you want as long as it adequately protects the conductors between it and the inverter AC combiner. Qualify the bus in the AC combiner under 705.12(D)(2)(3)(c).

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