Compact circuit breaker incorporating a polymer current limiter

A compact current limiting circuit breaker comprising:

• a circuit breaker housing;
• a first contact arranged at one end of a contact arm and a second contact arranged at one end of a line strap, said first and second contacts being arranged within said housing for transfer of current through an associated protected circuit;
• an operating mechanism within said housing arranged for separating said first and second contacts upon occurrence of an overcurrent condition in said protected circuit;
• a trip unit within said circuit breaker housing for articulating said operating mechanism for separation of said first and second contacts to thereby create an arc current between said first and second contacts upon occurrence of said overcurrent condition;
• a polymer current limiter including a polymeric conductor;
• said polymer current limiter having an arc rail arranged proximate said second contact for commutating said arc current into said polymer current limiter for rapid suppression of said arc current;
• and
• an interface, proximate to and in series with said polymeric conductor in said protected circuit, having a higher resistivity than said polymeric conductor whereby said arc current causes resistive heating at said interface resulting in rapid thermal expansion and vaporization of said polymeric conductor at said interface causing at least partial separation at said interface thereby causing rapid suppression of said arc current.