Patent ID: 8350414

Claim:
An electrical switch apparatus for use in connecting and disconnecting a DC power source and a load, said switch apparatus comprising first and second pairs of controllable electromechanical contacts coupled to said DC power source and said load for connecting said power source to said load when said contacts are closed, and disconnecting said power source from said load when said contacts are open to provide galvanic isolation between said DC power source and said load, a diode coupled to said electromechanical contacts to prevent electrical current from flowing from said load to said DC power source, a controllable semiconductor switch coupled across said power source, and a controller coupled to said electromechanical contacts and said controllable semiconductor switch for producing control signals for opening and closing said contacts and for turning said controllable semiconductor switch on and off, said controller being programmed to produce a control signal for turning said semiconductor switch on to momentarily short circuit said DC power source when at least one of said first and second pairs of electromechanical contacts transitions from a closed condition to an open condition.