Abstract: An improved transient voltage suppression system for use in an electrical power distribution system which includes at least one power line and a neutral or ground line. The system includes a suppression circuit for each power line of the power distribution system, with each suppression circuit being coupled between a corresponding power line and the neutral or ground line. Each suppression circuit includes a first and second metal oxide varistors each coupled in series with corresponding first and second switching resistors and thermally coupled thereto, and a third metal oxide varistor coupled in parallel with the series connections of the first and second metal oxide varistors and the first and second switching resistors. A capacitor is coupled in parallel with the third metal oxide varistor. Coupled between each suppression circuit and a corresponding power line is a fuse for protecting the components of the circuits from current surges.

Abstract: A transient voltage suppression system for use in an electrical power distribution system which includes at least one power line and a neutral or ground line. The system includes a suppression circuit for each power line of the power distribution system, with each suppression circuit being coupled between a corresponding power line and the neutral or ground line. Each suppression circuit includes a first metal oxide varistor coupled in series with a switching resistor and thermally coupled thereto, and a second metal oxide varistor coupled in parallel with the series connection of the first metal oxide varistor and switching resistor. The breakdown voltage rating of the second metal oxide varistor is greater than that of the first metal oxide varistor. A capacitor is coupled in parallel with the second metal oxide varistor. Coupled between each suppression circuit and a corresponding power line is a fuse for protecting the components of the circuits from current surges.