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How do I change the amp rating of a circuit breaker? Applies to Powerpact P and R, Masterpact NT and NW

Product Line:
Circuit Breakers

Environment:
Powerpact P, R and Masterpact NT and NW Circuit Breakers with these trip units:
Micrologic 2.0(A), 3.0(A), 5.0(A,P,H), 6.0(A,P,H)

Resolution:
For the above breakers and trip units, the Long-Time amp rating can be adjusted by these methods (also reference the below picture):
(1) ADJUST THE RATING PLUG IR DIAL - The trip unit has a Rating Plug Ir dial with various settings, typically from 0.4 to 1.0, which when multiplied times the Sensor Plug In value gives the breaker its Long-Time rating. Simply adjusting the Rating Plug Ir dial to another value to get a different Long-Time rating.*
(2) CHANGE THE SENSOR PLUG - The breaker has a Sensor Plug, and on the face shows it shows an In amp rating value. The In value is the absolute maximum Long-Time rating of that breaker. Changing the Sensor Plug to a different one of lower In value (50% minimum) changes the Long-Time rating of the breaker.
(3) BOTH OF THE ABOVE - At the same time, adjusting the rating plug and changing the sensor plug will give you a large variety of Long-Time ratings.*

Example #1
What are the minimum and maximum Long-Time ratings of a Powerpact 800A breaker with 5.0 trip unit?
  • For the minimum, adjust the Rating plug Ir dial to 0.4, and multiply that times the Sensor Plug value (In = 800A) to get the minimum rating of 320A (0.4 x 800A). *
  • For the maximum, adjust the Rating plug Ir dial to 1.0, and multiply that times the Sensor Plug value (In = 800A) to get the maximum rating of 800A (1.0 x 800A).
Example #2
What are the minimum and maximum Long-Time ratings of a Powerpact 800A breaker with 5.0 trip unit, after the Sensor Plug has been changed to 400A?
  • For the minimum, adjust the Rating plug Ir dial to 0.4, and multiply that times the new Sensor Plug value (In = 400A) to get the minimum rating of 160A (0.4 x 400A). *
  • For the maximum, adjust the Rating plug Ir dial to 1.0, and multiply that times the new Sensor Plug value (In = 400A) to get the maximum rating of 400A (1.0 x 400A).

*Note: To meet NEC 240-6(C), after adjusting the Rating Plug Ir dial, install the MICROTUSEAL Wire Seal Kit for Micrologic Trip Units. This seals the cover over the Rating Plug Ir Dial.



 
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