Surge protection device with thermal protection, current limiting, and failure indication

A surge protection device for a power distribution network, comprising:

• a) a plurality of identical circuits, each circuit comprising:
• i) a current limiter connected between a first input terminal and a bridge terminal;
• ii) a thermal protector connected between the bridge terminal and a central terminal;
• iii) a metal oxide varistor connected between the central terminal and a second input terminal;
• iv) a current sense resistor connected between the bridge terminal and the central terminal for distinguishing indication of current limiter open circuit;
• v) a thermal sense resistor connected between the central terminal and an indicator terminal for distinguishing indication of thermal protector open circuit;
• and
• vi) a bridge positioned between each current limiter and each metal oxide varistor for providing an isolating barrier and the bridge terminal for connecting the current limiter and the thermal protector;
• b) wherein the first input terminals of each identical circuit are connected together and connect to the power distribution network, the second input terminals of each identical circuit are connected together and connect to the power distribution network, and the indicators terminals are connected together.

A method of fabricating a surge protection device for a power distribution network, comprising:

• a) connecting a current limiter between a first input terminal and a bridge terminal, the first input terminal being connected to the power distribution network;
• b) connecting a thermal protector between the bridge terminal and a central terminal;
• c) connecting a metal oxide varistor between the central terminal and a second input terminal, the second input terminal being connected to the power distribution network;
• d) connecting a current sense resistor between the bridge terminal and the central terminal for distinguishing indication of current limiter open circuit;
• e) connecting a thermal sense resistor between the central terminal and an indicator terminal for distinguishing indication of thermal protector open circuit;
• and
• f) positioning a bridge between the current limiter and the metal oxide varistor for providing an isolating barrier and the bridge terminal for connecting the current limiter and the thermal protector.