The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 25, 1996
Filed:
Jun. 01, 1994
James A Bauer, Asheville, NC (US);
Denis A Mueller, Asheville, NC (US);
Henry A Wehrli, III, Monroeville, PA (US);
James D Smith, Monroeville, PA (US);
Eaton Corporation, Cleveland, OH (US);
Abstract
A circuit controller for selectively connecting a power source to a load includes a non-overcurrent protective electrical switching mechanism and a conductive polymer current limiter connected in series with the load for limiting the current which flows through the switching mechanism whenever the power source is selectively connected to the load. The conductive polymer current limiter may include a plurality of parallel conductive polymer positive temperature coefficient (PTC) resistors. The circuit controller may include an electrical switching mechanism which, under short circuit conditions, remains selectively connected to the load. The short circuit current which is limited by the conductive polymer current limiter continues to flow through the electrical switching mechanism. The switching mechanism may include a contactor having separable contacts, and may further include a circuit interrupter, in order to provide a separate circuit disconnection mechanism. The electrical switching mechanism may have a coil and the circuit controller may include a voltage sensor. The conductive polymer current limiter may have an output which has a voltage substantially less than the voltage of the power source whenever the short circuit current flows from the power source and through the current limiter. The voltage sensor may be connected to the output of the conductive polymer current limiter and may deenergize the coil in order to open the separable contacts of the contactor and disconnect the power source from the load whenever the voltage of the output drops below a predetermined threshold. The contactor may be a motor-starting contactor.