Patent · US Expired

Overcurrent protection circuit

US5689395A · kind A · utility

47Cited by
37References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 29, 1995
Grant dateNov 18, 1997
Priority date
Expiry dateNov 29, 2015

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH02H9/026
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

An overcurrent protection system which will give a rapid response to relatively small overcurrents. The system, which can be connected between an electrical power supply and an electrical load to form an operating circuit, and which when so connected protects the circuit from overcurrents, has a normal operating condition and a fault condition, and comprises: a circuit interruption element having, (1) a normal state which permits the flow of a normal current, I.sub.NORMAL, when the system is in the normal operating condition, and (2) a fault state which permits the flow of at most a reduced current, substantially less than I.sub.NORMAL, when the system is in the fault condition; and a control element, connected in series with the circuit interruption element, the control element having a variable resistance which (1) is low when the current in the system does not exceed the normal current, I.sub.NORMAL, by a predetermined current amount, and (2) increases by at least a predetermined resistance amount when the current in the system exceeds the normal current, I.sub.NORMAL, by the predetermined current amount; the circuit interruption element changing from its normal state to its fau…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.