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What does the calibration test consist of that a UL489 circuit breaker must pass?

CALIBRATION:
200% calibration at 25?C
The circuit breaker must trip within time limits which depend on the rating from three
minutes for a 30 A rated circuit breaker, up to 30 minutes over 2000 A.
135% calibration at 25?C
The circuit breaker must trip within two hours (for circuit breakers rated more than 50 A).
Calibration of adjustable instantaneous trip
The circuit breaker must trip within the range of 80-120% of the maximum marked
tripping current and 75-125% of the minimum marked tripping current.



CTA-ID : 9156
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