Based on the 1996 national electrical code.

  

  be different. Let’s investigate both aspects.

  

  

  Simply the Magnitude of the Current Flow. This Portion of the Curve is said to have an invarse time chaorteristic, which of the cb Will Tims Tim Leevelop Higher Level

  SINCE The Current Path (Including Both the Cb and the Conductor) Reacts to Heat, The OveralLALLOTING TEMPARANT THE EQUIPMES A FACOMES A FACTOR in AN ENCLOSURE..

  Other Factors That May Affect This Equipment Operation Temperature Include:

  Size and localized of the enclosure;

More than one Current-Carrying Device Housed in the Same Enclosure;

Level ofurrent each device is carrying; and

Environmental Conditions in the area of the equipment.

Factors are accounted frame circuit breaker fixed Switch Oem manufacturer for by the size imposed by the nec.

  

  Continuous loads

  "IT’s Critical for You to UNDERSTAND that this is a load at its maximum before unintererupted for at least through the house. Office lighting typically meetings this question.

  NEC SIZING RULES. SECS. 210-22 (C), 220-3 (A), 220-10 (B), and 384-16 (C) All related to the size runway according to the size.Three All Specify The Same Requirement:

  OCPD SIZE = 100% of NonContinuous Load + 125% of Continuous Load.

  Is the Inverse of 125% (0.80 = 1 ÷ 1.25) and, as such, the rules are indeedical in their end requirement.

  

  100%-lated devices

  operation.

  Of the its rating for Continuous loading unless it marked as such by the manuoFacturer.

  Their full rating as long as the assembly is list and conDuctors are properly connected.

  The following are exmples of size rules.

  Example 1: 50A Continuous Load and 125a NonContinuous Load.

  OCPD = 100% NonContinuous Load + 125% Continuous Load = (1.00 x 125A) + (1.25 x 50A) = 187.5A

  Therefore, a 200A OCPD is Needed. IF A 100%-lated Cb is chosen, a 175a rate (125A + 50A) is acceptable.

  Example 2: 300a noncontinuous load.

  A 300a device is acceptable; a 100%-lated device is not needed since the load is noncontinuous.

  Example 3: 200A Continuous Load.

  OCPD = 100% NonContinuous Load + 125% Continuous Load = (1.00 x 0A) + (1.25 x 200A) = 250A

  TheReface, a 250a device is needed. Frame Circuit Breaker Fixed Switch Oem ManuFactuer IF A 100%-lated CB is Selected, A 200A RATING is Permitted.

  Example 4: 16A Continuous and 30A NonContinuous.

  OCPD = 100% NonContinuous Load + 125% Continuous Load = (1.00 x 30A) + (1.25 x 16A) = 50A

  Then, then

  For more information, Read "overcurrential protering device size."


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