Convertible locking arrangement on breakers

In an exemplary embodiment of the invention, a locking mechanism comprising a blocking member sized to fit within the elongated slot through which a circuit breaker handle extends is disclosed. The blocking member may be seated adjacent the circuit breaker handle within the elongated slot and may snap or otherwise be locked into place to prevent the circuit breaker handle from moving within the slot. Thus, if the blocking member is placed within the elongated slot when the circuit breaker handle is in an OFF position, then the circuit breaker handle will be locked in the OFF position. The blocking member can be converted for locking the circuit breaker handle in an ON position. Then, when the blocking member is placed within the elongated slot when the circuit breaker handle is in an ON position, then the circuit breaker handle will be locked in the ON position. Once the blocking member is made for use in locking the circuit breaker in an ON condition, it cannot be converted back for use as a blocking member for locking the circuit breaker handle in an OFF position.