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US4937757A Expired / Lapsed US ⏱️ 0.0 years remaining

Digital circuit interrupter with selectable trip parameters

Assignee: SVENSKA ROTOR MASKINER PO BOX 15085 S-104 65 STOCKHOLM SWEDEN A CORP OF KINGDOM OF SWEDEN AB
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Filing: 1988-10-11
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Granted: 1990-06-26
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Expires: 2008-10-11
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Abstract

Abstract A digital circuit interrupter includes a microprocessor programmed for tailored overcurrent protection to power systems. A communication link permits the over-current set points to be selectively set within the microprocessor memory from a remote location. The over-current trip parameters are then derived by an algorithm which resides in the microprocessor memory.

Inventors

  • 👤 John J. Dougherty

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 07:44
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/006; H02H3/08; H02H3/093; H02H3/0935

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 96 words
A digital circuit interrupter with selectable trip parameters comprising: current means for determining circuit current in an electrical power distribution system; a microprocessor connected with said current means for determining the occurrence of an overcurrent through said electrical power distribution system and interrupting said overcurrent after a calculated time delay; and memory means connected with said microprocessor and containing fixed data points corresponding to thermal and magnetic circuit interruption devices, said memory means further including a logarithmic interpolation algorithm for interpolating between said fixed data points to generate a continuous representation of said calculated time delay.
Claim 2
Dependent Claim 96 words
A digital circuit interrupter with selectable trip parameters comprising: current means for determining circuit current in an electrical power distribution system; a microprocessor connected with said current means for determining the occurrence of an overcurrent through said electrical power distribution system and interrupting said overcurrent after a calculated time delay; and memory means connected with said microprocessor and containing fixed data points corresponding to thermal and magnetic circuit interruption devices, said memory means further including a logarithmic interpolation algorithm for interpolating between said fixed data points to generate a continuous representation of said calculated time delay.
Claim 3
Dependent Claim 34 words
The digital circuit interrupter of claim 1 including a cooling algorithm in combination with said interpolation algorithm to simulate cooling of cables within said electrical power delivery system after cessation of said overcurent condition.
Claim 4
Dependent Claim 15 words
The digital circuit interrupter of claim 1 wherein said memory means comprise electrically erasable memory.
Claim 5
Dependent Claim 27 words
The digital circuit interrupter of claim 1 wherein said fixed data points are installed within said memory means at the time of manufacturing said digital circuit interrupter.
Claim 6
Dependent Claim 27 words
The digital circuit interrupter of claim 1 wherein said fixed data points are installed within said memory means at the time of utilizing said digital circuit interrupter.
Claim 7
Dependent Claim 121 words
An electrical distribution system having tailored protection parameters comprising, in combination: a main supply conductor connected with a plurality of branch supply conductors; an electronic circuit interrupter serially connected within said main supply conductor and including interruption means, a microprocessor and memory means; and at least one magnetic relay circuit interrupter serially connected within one of said branch supply conductors for protecting electrical equipment connected with said one branch supply conductor, said memory means including fixed protection parameters corresponding to said magnetic relay circuit interrupter and a logarithmic interpolation algorithm whereby said microprocessor calculates an ideal tripping-time curve from said fixed protection parameters upon the occurrence of an overcurrent condition within said main supply conductor or said one branch supply conductor.
Claim 8
Dependent Claim 121 words
An electrical distribution system having tailored protection parameters comprising, in combination: a main supply conductor connected with a plurality of branch supply conductors; an electronic circuit interrupter serially connected within said main supply conductor and including interruption means, a microprocessor and memory means; and at least one magnetic relay circuit interrupter serially connected within one of said branch supply conductors for protecting electrical equipment connected with said one branch supply conductor, said memory means including fixed protection parameters corresponding to said magnetic relay circuit interrupter and a logarithmic interpolation algorithm whereby said microprocessor calculates an ideal tripping-time curve from said fixed protection parameters upon the occurrence of an overcurrent condition within said main supply conductor or said one branch supply conductor.
Claim 9
Dependent Claim 122 words
An electrical distribution system having tailored protection parameters comprising, in combination: a main supply conductor connected with a plurality of branch supply conductors; an electronic circuit interrupter serially connected within said main supply conductor and including interruption means, a microprocessor means and memory means; and at least one thermal relay circuit interrupter serially connected within one of said branch supply conductors for protecting electrical equipment connected with said one branch supply conductor, said memory means including fixed protection parameters corresponding to said thermal relay circuit interrupter and a logarithmic interpolation algorithm whereby said microprocessor calculates an ideal tripping-time curve from said fixed protection parameters upon the occurrence of an overcurrent condition within said main supply conductor or said one branch supply conductor.
Claim 10
Dependent Claim 122 words
An electrical distribution system having tailored protection parameters comprising, in combination: a main supply conductor connected with a plurality of branch supply conductors; an electronic circuit interrupter serially connected within said main supply conductor and including interruption means, a microprocessor means and memory means; and at least one thermal relay circuit interrupter serially connected within one of said branch supply conductors for protecting electrical equipment connected with said one branch supply conductor, said memory means including fixed protection parameters corresponding to said thermal relay circuit interrupter and a logarithmic interpolation algorithm whereby said microprocessor calculates an ideal tripping-time curve from said fixed protection parameters upon the occurrence of an overcurrent condition within said main supply conductor or said one branch supply conductor.
Claim 11
Dependent Claim 119 words
An electrical distribution system having tailored protection parameters comprising, in combination: a main supply conductor connected with a plurality of branch supply conductors; an electronic circuit interrupter serially connected within said main supply conductor and including interruption means, a microprocessor and memory means; and at least one thermal-magnetic circuit interrupter serially connected within one of said branch supply conductors for protecting electrical equipment connected with said one branch supply conductor, said memory means including fixed protection parameters corresponding to said thermal-magnetic circuit interrupter and a logarithmic interpolation algorithm whereby said microprocessor calculates an ideal tripping-time curve from said fixed protection parameters upon the occurrence of an overcurrent condition within said main supply conductor or said one branch supply conductor.
Claim 12
Dependent Claim 119 words
An electrical distribution system having tailored protection parameters comprising, in combination: a main supply conductor connected with a plurality of branch supply conductors; an electronic circuit interrupter serially connected within said main supply conductor and including interruption means, a microprocessor and memory means; and at least one thermal-magnetic circuit interrupter serially connected within one of said branch supply conductors for protecting electrical equipment connected with said one branch supply conductor, said memory means including fixed protection parameters corresponding to said thermal-magnetic circuit interrupter and a logarithmic interpolation algorithm whereby said microprocessor calculates an ideal tripping-time curve from said fixed protection parameters upon the occurrence of an overcurrent condition within said main supply conductor or said one branch supply conductor.
Claim 13
Dependent Claim 19 words
The electrical distribution system of claims 6 or 7 or 8 wherein said memory means comprise electrically erasable memory.
Claim 14
Dependent Claim 125 words
An electrical distribution system having tailored protection parameters comprising, in combination: a main supply conductor connected with a plurality of branch supply conductors; an electronic circuit interrupter serially connected within said main supply conductor and including interruption means, microprocessor and memory means; and at least one voltage relay or at least one power relay connected within one of said branch supply conductors for protecting electrical equipment connected with said one branch supply conductor, said memory means including fixed protection parameters corresponding to said voltage relay or said power relay and a logarithmic interpolation algorithm whereby said microprocessor calculates an ideal tripping-time curve from said fixed protection parameters upon the occurrence of an overcurrent condition within said main supply conductor or said one branch supply conductor.
Claim 15
Dependent Claim 125 words
An electrical distribution system having tailored protection parameters comprising, in combination: a main supply conductor connected with a plurality of branch supply conductors; an electronic circuit interrupter serially connected within said main supply conductor and including interruption means, microprocessor and memory means; and at least one voltage relay or at least one power relay connected within one of said branch supply conductors for protecting electrical equipment connected with said one branch supply conductor, said memory means including fixed protection parameters corresponding to said voltage relay or said power relay and a logarithmic interpolation algorithm whereby said microprocessor calculates an ideal tripping-time curve from said fixed protection parameters upon the occurrence of an overcurrent condition within said main supply conductor or said one branch supply conductor.

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1993-06-25 1993-12-25 1994-06-26 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1997-06-25 1997-12-25 1998-06-26 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2001-06-25 2001-12-25 2002-06-26 $7700.00 Window Closed / Lapsed

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