Abstract: A metal oxide varistor module, and variations thereof for use in surge protectors and the like combining internally a thermally activated disconnect means and an excessive current disconnect means, such that when the module is subject to excessive overvoltage or overcurrent conditions, the connection is interrupted from the phase to neutral, phase to ground and any other combination of voltage or current before the metal oxide varistor device is physically damaged, ruptured or cracked.

Abstract: A surge protector or transient suppressors for AC power lines having its components mounted on a circuit board. The metalization of the board are configured to present as large a surface area as possible, given the topology of the board, to the flow of current. A return conductor is placed on the opposite side of the board with a large surface area corresponding to the first conductor. The magnetic field between the two conductors is substantially cancelled. This configuration reduces the magnetic field intensities associated with the flow of current, thereby reducing self-inductance.