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US4007401A Expired / Lapsed US ⏱️ 0.0 years remaining

Current sensitive circuit protection system

Assignee: Westinghouse Electric Corp
•
Filing: 1974-09-09
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Granted: 1977-02-08
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Expires: 1994-09-09
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Abstract

Abstract An electrical control system which is utilized for opening a circuit breaker which is connected to a load to be protected. The control system comprises a unitary current sensor module which senses current flowing in the load to be protected. The sensor is adapted to have connected at the output thereof a load resistor which is capable of cooperating with the sensed current to provide a range of voltage over which a set of plug-in modules are operable to either provide an indication of characteristics associated with the current or the load or to provide an output function which is adapted to open the circuit breaker. The load resistor is replaceable with other load resistors so that the voltage range may be maintained even though the expected value of currents to be sensed by the sensor may change depending upon the load and other circuit characteristics.

Inventors

  • 👤 Donald S. Kimmel
  • 👤 Wardell Gary
  • 👤 Glenn R. Taylor

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 12:54
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/08; H02H3/10; H02H1/00; H02H3/093

Claims Analysis

Total Claims: 13
Claim 1
Independent Claim 128 words
An electrical circuit protecting device, comprising: sensor means for sensing circuit current in an electrical circuit, said sensor means having an output for providing an output current related to said circuit current; replaceable load resistor means connected to said output of said sensor means for converting said output current into a voltage the value of which is variable within a predetermined voltage range for a predetermined range of said circuit current; a replaceable module connected in parallel circuit relationship with said load resistor means, said module being capable of initiating a circuit breaker trip function, said module being operable over said predetermined range of said voltage; and circuit breaker trip means connected to said module for opening said electrical circuit when said trip function occurs in said module.
Claim 2
Dependent Claim 128 words
An electrical circuit protecting device, comprising: sensor means for sensing circuit current in an electrical circuit, said sensor means having an output for providing an output current related to said circuit current; replaceable load resistor means connected to said output of said sensor means for converting said output current into a voltage the value of which is variable within a predetermined voltage range for a predetermined range of said circuit current; a replaceable module connected in parallel circuit relationship with said load resistor means, said module being capable of initiating a circuit breaker trip function, said module being operable over said predetermined range of said voltage; and circuit breaker trip means connected to said module for opening said electrical circuit when said trip function occurs in said module.
Claim 3
Dependent Claim 44 words
The combination as claimed in claim 1 wherein there are a plurality of said modules each of which is connectable in parallel circuit relationship with said load resistor means and with each other, each of which is capable of independently initiating said trip function.
Claim 4
Dependent Claim 34 words
The combination as cliamed in claim 1 wherein there is a second replaceable module which is capable of performing an indicating function, said second module being operable over said predetermined range of said voltage.
Claim 5
Dependent Claim 17 words
The combination as claimed in claim 1 wherein said replaceable module comprises an inverse time overload module.
Claim 6
Dependent Claim 16 words
The combination as claimed in claim 1 wherein said replaceable module comprises an instantaneous overcurrent module.
Claim 7
Dependent Claim 16 words
The combination as claimed in claim 1 wherein said replaceable module comprises a phase failure module.
Claim 8
Dependent Claim 16 words
The combination as claimed in claim 1 wherein said replaceable module comprises an underload logic module.
Claim 9
Dependent Claim 16 words
The combination as claimed in claim 1 wherein said replaceable module comprises a phase imbalance module.
Claim 10
Dependent Claim 17 words
The combination as claimed in claim 3 wherein said second replaceable module comprises a field test panel.
Claim 11
Dependent Claim 17 words
The combination as claimed in claim 3 wherein said second replaceable module comprises an overload condition indicator.
Claim 12
Dependent Claim 127 words
An electrical motor starter comprising: sensor means for sensing circuit current in an electrical circuit, said sensor means having an output for providing an output current related to said circuit current; replaceable load resistor means connected to said output of said sensor means for converting said output current into a voltage the value of which is variable within a predetermined voltage range for a predetermined range of said circuit current; a replaceable module connected in parallel circuit relationship with said load resistor means, said module being capable of initiating a circuit breaker trip function, said module being operable over said predetermined range of said voltage; and circuit breaker trip means connected to said module for opening said electrical circuit when said trip function occurs in said module.
Claim 13
Dependent Claim 127 words
An electrical motor starter comprising: sensor means for sensing circuit current in an electrical circuit, said sensor means having an output for providing an output current related to said circuit current; replaceable load resistor means connected to said output of said sensor means for converting said output current into a voltage the value of which is variable within a predetermined voltage range for a predetermined range of said circuit current; a replaceable module connected in parallel circuit relationship with said load resistor means, said module being capable of initiating a circuit breaker trip function, said module being operable over said predetermined range of said voltage; and circuit breaker trip means connected to said module for opening said electrical circuit when said trip function occurs in said module.

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USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-02-08 1980-08-09 1981-02-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-02-08 1984-08-09 1985-02-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-02-08 1988-08-09 1989-02-08 $7700.00 Window Closed / Lapsed

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