Abstract:
A current-limiting sparkgap assembly of the type that utilizes a magnetic field to stretch arcs in the discharge circuit of the assembly thereby forcing the arcs against cooling surfaces to extinguish them, characterized by having an auxiliary electromagnetic field-generating means that selectively resists the arc-stretching movement of arcs in the assembly to delay the extinguishing operation of the assembly until the surge current has been completely discharged to ground.
Abstract:
An overvoltage surge arrester for relatively high voltage applications is provided with a voltage grading circuit comprising a relatively low exponent resistor in parallel with a relatively high exponent resistor, for preventing spurious operation of the arrester under conditions in which the outside surface of the porcelain housing becomes contaminated with a conductive film. Also disclosed is a grading circuit in which a linear resistor is additionally connected in series with the high exponent non-linear resistor of the above circuit.
Abstract:
A lightning arrester having a current limiting spark gap assembly with means therein for regulating the movement of arcs established within the assembly so that the arcs are prevented from building a high voltage when they are discharging a current in excess of a predetermined value. The regulating means are also effective to allow low current arcs to rapidly and consistently build high voltages.