Abstract: A surge protection device (SPD) module includes: a housing; a plurality of metal oxide varistor (MOV) wafers, respective ones of the plurality of MOV wafers having electrical characteristics that reduce an imbalance in current between the respective ones of the plurality of MOV wafers in response to an overvoltage event; and one or more electrodes, the plurality of MOV wafers and the one or more electrodes being alternately arranged in the housing.

Abstract: A surge protective device (SPD) module includes first, second and third terminals, a node connected to the third terminal, a varistor stack, a first branch, and a second branch. The varistor stack assembly includes a first varistor, a second varistor, and a node electrode interposed between the first and second varistors. The node electrode is electrically connected to the first and second varistors and includes the node. The first branch includes the first varistor connected between the first terminal and the node, and a first thermal disconnector mechanism configured to disconnect the first varistor from the first terminal or the node. The second branch includes the second varistor connected between the second terminal and the node, and a second thermal disconnector mechanism configured to disconnect the second varistor from the second terminal or the node.