Electrical Distribution Equipment
An insulated case circuit breaker is a molded case circuit breaker with an integral 2-step stored-energy mechanism. They have the functionality of an iron-frame breaker, or a low-voltage-power breaker with a molded plastic instead of an iron frame.
Masterpact MTZ, NW, NT breakers are Molded Case breakers, but are considered to be Insulated Case breakers due to the inclusion of the 2 step stored energy mechanism (charging handle).
Powerpact B, H, J, L, M, P, and R breakers are Molded Case breakers.