Patent · US Expired

Distribution transformer secondary circuit breaker

US3983454A · kind A · utility

22Cited by
10References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 12, 1974
Grant dateSep 28, 1976
Priority date
Expiry dateAug 12, 1994

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01H73/50
  • WIPO fieldElectrical machinery, apparatus, energy
  • WIPO sectorElectrical engineering

Abstract

A distribution transformer having a secondary circuit breaker utilizing a movable bridging contact between two stationary contacts for completing a series circuit therethrough. The movable bridging contact is spring biased towards an open position separated from the stationary contacts, but with the circuit breaker in the normally closed position is held in engagement with the stationary contacts by a latching mechanism which is responsive to a bimetal or magnetic trip element to allow the circuit breaker to trip open during overload conditions. The conducting bridging contact completes a series circuit through the circuit breaker which opens during circuit interruption. The secondary circuit breaker can also, if desired, be provided with a signal-light circuit which activates a signal light, on the exterior housing of the transformer, when current through the circuit breaker exceeds a low signal overload value which is less than the trip value. The signal light circuit is reset by turning the operator handle, which is located on the transformer housing, past the on position away from the off position. An emergency overload control is provided for increasing the tripping level of t…

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