Back to results
US 4,174,530 AGranted
Voltage surge arrester device
AssigneeGeneral Electric Company
InventorsJames S. Kresge, Eugene C. Sakshaug
Life of this patent
Estimating the term…
Abstract
Voltage surge arrester devices having predetermined shunt gap sparkover voltages are provided by the series combination of high- and low-exponent varistors. In one embodiment the high-exponent varistor comprises zinc oxide and the low-exponent varistor comprises silicon carbide.
Claims9
An overvoltage surge arrester comprising:
- at least one high-exponent varistor having an exponent greater than 10 for electrical connection between a voltage line and ground;
- at least one low-exponent varistor having an exponent less than 10 in series with said high-exponent varistor for providing a more rapid voltage increase than for the high-exponent varistor;
- and
- at least one shunt gap shunting said low-exponent varistor and a portion of said high-exponent varistor for reducing the arrester voltage during a condition of electrical overvoltage.
1 more element
An electrical overvoltage surge arrester comprising:
- at least one first varistor having a first exponent for electrical coupling between a voltage line and ground for causing surge current to flow from said line to ground upon the condition of a voltage surge;
- at least one second varistor having a second exponent and electrically connected in series with said first varistor, the exponent of said second varistor being lower than the exponent of said first varistor for causing a faster voltage increase across said second varistor;
- and
- at least one shunt gap having a predetermined sparkover voltage across said first and second varistors for shunting current from said first and second varistors when said predetermined voltage appears across said shunt gap.
1 more element
Dependencies are inferred from the claim text.