A circuit breaker apparatus comprising: a housing; an electrical power inlet; an electrical power outlet; a main circuit breaker positioned in said housing, said main circuit breaker having a pair of contactors (250, 254) therein, one of said pair of contactors (250, 254) electrically connected or interconnected to said electrical power inlet and to said electrical power outlet; a grounding switch positioned in said housing, said grounding switch having a pair of contactors (258, 260) therein, one of said pair of contactors (258, 260) of said grounding switch being electrically connected or interconnected to ground, said grounding switch being in non-longitudinal relation to said main circuit breaker; and a mechanical linkage movable between a first position and a second position, said first position actuating said main circuit breaker such that the pair of contactors (250, 254) of said main circuit breaker are closed and such that the pair of contactors (258, 260) of said grounding switch are open, said mechanical linkage movable to a second position actuating said main circuit breaker such that the pair of contactors (250, 254) of said main circuit breaker are open and such that the pair of contactors (258, 260) of said grounding switch are closed, wherein said mechanical linkage comprises: an actuator that is movable between a first position and a second position, said actuator movable from the first position to the second position upon detection of a fault in electrical power from said electrical power inlet; and characterised in by a yoke connected to said actuator, said yoke connected to one of said pair of contactors (250, 254) of said main circuit breaker and to one of said pair of contactors (258, 260) of said grounding switch, a movement of said actuator to the second position causing the pair of contactors (250, 254) of said main circuit breaker to open and the pair of contactors (258, 260) of said grounding switch to close. a housing; an electrical power inlet; an electrical power outlet; a main circuit breaker positioned in said housing, said main circuit breaker having a pair of contactors (250, 254) therein, one of said pair of contactors (250, 254) electrically connected or interconnected to said electrical power inlet and to said electrical power outlet; a grounding switch positioned in said housing, said grounding switch having a pair of contactors (258, 260) therein, one of said pair of contactors (258, 260) of said grounding switch being electrically connected or interconnected to ground, said grounding switch being in non-longitudinal relation to said main circuit breaker; and a mechanical linkage movable between a first position and a second position, said first position actuating said main circuit breaker such that the pair of contactors (250, 254) of said main circuit breaker are closed and such that the pair of contactors (258, 260) of said grounding switch are open, said mechanical linkage movable to a second position actuating said main circuit breaker such that the pair of contactors (250, 254) of said main circuit breaker are open and such that the pair of contactors (258, 260) of said grounding switch are closed, wherein said mechanical linkage comprises: an actuator that is movable between a first position and a second position, said actuator movable from the first position to the second position upon detection of a fault in electrical power from said electrical power inlet; and characterised in by a yoke connected to said actuator, said yoke connected to one of said pair of contactors (250, 254) of said main circuit breaker and to one of said pair of contactors (258, 260) of said grounding switch, a movement of said actuator to the second position causing the pair of contactors (250, 254) of said main circuit breaker to open and the pair of contactors (258, 260) of said grounding switch to close. an actuator that is movable between a first position and a second position, said actuator movable from the first position to the second position upon detection of a fault in electrical power from said electrical power inlet; and characterised in by a yoke connected to said actuator, said yoke connected to one of said pair of contactors (250, 254) of said main circuit breaker and to one of said pair of contactors (258, 260) of said grounding switch, a movement of said actuator to the second position causing the pair of contactors (250, 254) of said main circuit breaker to open and the pair of contactors (258, 260) of said grounding switch to close.