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

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

Applies to all breakers listed to UL489 and CSA 22.2 

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

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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