A THERMAL-MAGNETIC TRIP ELEMENT combines the thermal and magnetic trip elements
into a single unit. A TRIP-FREE circuit breaker will trip (open) even if the operating mechanism is held
in the ON position. A TRIP-FREE circuit breaker would be used on non-essential circuits.
A NONTRIP-FREE circuit breaker can be bypassed by holding the operating mechanism ON. A
NONTRIP-FREE circuit breaker would be used for emergency or essential equipment circuits.