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Should circuit breakers be selected by symmetrical AIC rating or asymetrical? What is the conversion factor?

Issue:
Should circuit breakers be selected by symmetrical AIC rating or asymetrical?  What is the conversion factor?

Product Line:
UL listed Molded case circuit breakers

Environment:

Cause:

Resolution:
Breaker AIR ratings are listed as RMS symmetrical.

The conversion from symetrical to asymmetrical depends on the powerfactor, examples below.  Also see attachment page 3.
100 percent powerfactor  asym = 1.414 x sym
20 percent powerfactor  asym = 2.183 x sym  (most UL listed breakers with AIR above 10kA are tested at 20% PF)

CTA-ID : 3338
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