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

Issue:
What is the endurance rating for the thermal magnetic breakers?
What is the endurance rating for electronic breakers?
What is the maximum number of operations for a circuit breaker?
How many times can a breaker be turned on and off?
How many times can be a breaker be switched?

Product Line:
Circuit Breakers

Environment:
Applies to all breakers listed to UL489 and CSA 22.2 

Resolution:
Circuit Breakers are tested to UL489 and CSA 22.2. For endurance, both thermal/magnetic and electronic circuit breakers must successfully complete the number of operations shown in the below table.
  • Power factor shall be 0.75 to 0.80 lagging.
  • Starting in the "open" position, the breaker is "closed", then "opened" (this counts as one operation)
  • The Full-Load Operations Test is done at rated current and voltage
  • The No-Load Operations Test is done following the Full-Load Test
Frame Size Amperes Full Load Operations No Load Operations
0-100 6,000 4,000
101-225 4,000 4,000
226-600 1,000 5,000
601-800 500 3,000
801-2500 500 2,000
2501-4000 400 1,000

NOTES:
Circuit breakers are not tested until they fail, so the "maximum" number of operations is not known.
Environmental factors affect the life of a breaker, so the number of test operations in the table should not be interpreted as a guaranteed number in actual use.
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