Circuit breaker test

Electrical Testing Talk Apparatus Testing
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![image|375x500](upload://n5qkArL3ecfHVi0t2mRMdbC7uD4.jpeg

Hello everyone, I was trying to understand breaker curves alitte bit better. An why we use the NETA 100.7 as well and where I could possibly look up table 3,NEMA AB 4-2017. If there is any videos or advice that anyone has I highly appreciate it.

Thank you

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Can you rephrase your question?
I think what you are asking is what “spec” we should be primary testing MCCBs to. Manufacturer trip curves should be used, but NETA acknowledges they may not be available and offers table 100.7.
100.7 is derived from AB4. The AB4 spec (so also 100.7) is incredibly broad. My personal opinion is it would be very difficult to “fail” a breaker using AB4 spec.
Manufacturer spec, AB4 spec, job spec may be 3 different things.

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I am horrible at at wording things, but you did answer my question. Thank you

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Also, NEMA AB4 is a free electronic copy on the NEMA website:

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