Abstract: A surge suppressor module includes a power conductor, a ground conductor, and a housing including an opening and a plurality of dovetail groove mechanisms and arcuate ground bus bars for electrically and mechanically mounting a corresponding surge suppressor module. An alternating current surge suppressor circuit is housed by the housing. The circuit receives the power and ground conductors through the opening of the housing. The circuit electrically connects the ground conductor to the plurality of arcuate ground bus bars for electrically and mechanically mounting a corresponding surge suppressor module, in order to provide a common ground connection thereto.

Abstract: A surge counter/detector apparatus includes current sensors communicating with power lines to sense a surge condition. A trigger circuit communicates with the current sensors and outputs a first signal in response to the sensed surge condition. The trigger circuit is reset and enabled by a second signal in order to enable subsequent output of the first signal. A processor detects the first signal from the trigger circuit and responsively increments and displays a count value at a display. The processor provides the second signal having a first state to reset the trigger circuit and a second state to enable the trigger circuit. The processor includes a timer to vary a time between (a) detecting the first signal, and (b) resetting and enabling the trigger circuit.

Abstract: A surge suppressor module includes a power conductor, a ground conductor, and a housing including an opening and a plurality of dovetail groove mechanisms and arcuate ground bus bars for electrically and mechanically mounting a corresponding surge suppressor module. An alternating current surge suppressor circuit is housed by the housing. The circuit receives the power and ground conductors through the opening of the housing. The circuit electrically connects the ground conductor to the plurality of arcuate ground bus bars for electrically and mechanically mounting a corresponding surge suppressor module, in order to provide a common ground connection thereto.

Abstract: A surge counter/detector apparatus includes current sensors communicating with power lines to sense a surge condition. A trigger circuit communicates with the current sensors and outputs a first signal in response to the sensed surge condition. The trigger circuit is reset and enabled by a second signal in order to enable subsequent output of the first signal. A processor detects the first signal from the trigger circuit and responsively increments and displays a count value at a display. The processor provides the second signal having a first state to reset the trigger circuit and a second state to enable the trigger circuit. The processor includes a timer to vary a time between (a) detecting the first signal, and (b) resetting and enabling the trigger circuit.

Abstract: A surge protection device includes terminals adapted to receive a power source voltage and surge protection circuits, each of which includes a thermal fuse spring, one or more metal oxide varistors (MOVs), and one or more fuse traces corresponding to the MOVs. The thermal fuse spring, one of the fuse traces and the corresponding one of the MOVs are electrically interconnected in series between the terminals, in order to form a series electrical connection therebetween. The thermal fuse spring is adapted to disconnect the series electrical connection between the terminals under first fault conditions including a first current of first duration through one of the MOVs. The thermal fuse spring and each of the fuse traces are adapted to cooperatively disconnect a corresponding one of the series electrical connections between the terminals under second fault conditions including a second greater current of second lesser duration through one of the MOVs.

Abstract: A surge protection device includes terminals adapted to receive a power source voltage and surge protection circuits, each of which includes a thermal fuse spring, one or more metal oxide varistors (MOVs), and one or more fuse traces corresponding to the MOVs. The thermal fuse spring, one of the fuse traces and the corresponding one of the MOVs are electrically interconnected in series between the terminals, in order to form a series electrical connection therebetween. The thermal fuse spring is adapted to disconnect the series electrical connection between the terminals under first fault conditions including a first current of first duration through one of the MOVs. The thermal fuse spring and each of the fuse traces are adapted to cooperatively disconnect a corresponding one of the series electrical connections between the terminals under second fault conditions including a second greater current of second lesser duration through one of the MOVs.

Abstract: A power switch connecting a load to an ac source is turned off when the RMS value of the supply voltage is outside selected limits and is turned back on when the RMS voltage returns to within the limits. Adaptive hysteresis is applied to the switch controller to eliminate chattering of the power switch when the voltage fluctuates around the selected limits. To this end, the selected limits are repetitively, incrementally narrowed each time the power switch is turned off and back on a selected number of times, such as twice, within a selected time interval. The RMS voltage is rapidly determined from samples gathered over ¼ cycle so that the voltages in a three phase system can be successively repetitively calculated. Phase loss is rapidly determined by checking for the leading edge of a square wave generated from the supply voltage wave form.

Abstract: A surge suppression network for single and multiphase ac systems has a voltage clamping device connected in series with a gated crowbar device across the supply voltage in parallel with the load to be protected. A trigger circuit gates the crowbar device on in response to a specified rate of change of the supply voltage indicative of a surge. For higher levels of surge current shunting, pluralities of clamping devices and crowbar devices can be connected in parallel with a single trigger circuit simultaneously turning on all of the crowbar devices for each phase. For crowbar devices such as TRIACs with different response characteristics to positive and negative surges and for unipolar devices such as SCRs, positive and negative subnetworks are connected in anti-parallel across the load.