US4825328A
Expired / Lapsed
US
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Three phase electrical load protection device
Assignee: Watsco Components Inc
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Filing: 1987-06-12
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Granted: 1989-04-25
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Expires: 2007-06-12
Abstract
Abstract A three phase electrical load protection device is disclosed including an input transducer for detecting each phase voltage and the direction of rotation of the phases of a three phase power system. A control monitor is disclosed for monitoring signals from the input transducer representative of the highest and lowest phase voltages and the direction of rotation of the phases for controlling an output device for disconnecting the electrical load when improper supply conditions are detected and monitored.
Inventors
- 👤 Lowell F. Izaguirre, Sr.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 23:54
CPC Classifications
H; H02; H02H; H02H11/00; H02H11/004; H02H3/00; H02H3/20; H02H3/207
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
156 words
An input transducer for a multiphase electrical power system to provide a first signal and a second signal representative of the highest and lowest voltages, respectively, of any of the phases of the power system, said input transducer comprising in combination: means for rectifying the voltage of each phase and charging a first storage means to a voltage value representative of the highest voltage present on said phase; first means for coupling the voltage value of each said first storage means representative of the highest voltage present for each phase to charge a second storage means to a voltage value representative of the highest voltage present on any phase of the power system; and second means for coupling the voltage value of each said first storage means representative of the highest voltage present to discharge a third storage means to a voltage value representative of the lowest voltage present on any phase of the power system.
Claim 2
Dependent Claim
156 words
An input transducer for a multiphase electrical power system to provide a first signal and a second signal representative of the highest and lowest voltages, respectively, of any of the phases of the power system, said input transducer comprising in combination: means for rectifying the voltage of each phase and charging a first storage means to a voltage value representative of the highest voltage present on said phase; first means for coupling the voltage value of each said first storage means representative of the highest voltage present for each phase to charge a second storage means to a voltage value representative of the highest voltage present on any phase of the power system; and second means for coupling the voltage value of each said first storage means representative of the highest voltage present to discharge a third storage means to a voltage value representative of the lowest voltage present on any phase of the power system.
Claim 3
Dependent Claim
98 words
The input transducer as set forth in claim 1, wherein said multi-phase power system comprises a conventional three-phase power system in which each phase differs by one-third of a cycle, said input transducer further comprising a phase reverse detector including means for rotating signals from the first and third phase by substantially ninety degrees and then summing such signals such that a positive voltage signal is produced if the second phase signal is ahead of the first phase signal and a near-zero voltage signal is produced if the first phase signal is ahead of the second phase signal.
Claim 4
Dependent Claim
55 words
The input transducer as set forth in claim 2, wherein each said storage means comprises a capacitor and wherein said second means for coupling the voltage value of each said first storage means comprises a resistive divider connected to a diode allowing said third storage means to discharge through said diode and said resistive divider.
Claim 5
Dependent Claim
35 words
The input transducer as set forth in claim 3, further comprising an input transformer having primary windings connected in a WYE configuration to the three-phase power system and secondary windings connected to said rectifying means.
Claim 6
Dependent Claim
35 words
The input transducer as set forth in claim 4, further including power supply means connected to each of said phases of said secondary windings of said transformer for providing rectified positive voltage and negative voltage.
Claim 7
Independent Claim
148 words
A method for providing a first signal and a second signal representative of the highest and the lowest voltages, respectively, of any of the phases of a multi-phase electrical power system, comprising the steps of: rectifying the voltage of each phase and charging a first storage means for each phase to a voltage value representative of the highest voltage present on such phase; coupling the voltage value of each said first storage means representative of the highest voltage present for each phase to charge a second storage means to a voltage value representative of the highest voltage present on any phase of the power system; and coupling the voltage value of each said first storage means representative of the highest voltage present of said phase to discharge a third storage means to a voltage value representative of the lowest voltage present on any phase of the power system.
Claim 8
Independent Claim
148 words
A method for providing a first signal and a second signal representative of the highest and the lowest voltages, respectively, of any of the phases of a multi-phase electrical power system, comprising the steps of: rectifying the voltage of each phase and charging a first storage means for each phase to a voltage value representative of the highest voltage present on such phase; coupling the voltage value of each said first storage means representative of the highest voltage present for each phase to charge a second storage means to a voltage value representative of the highest voltage present on any phase of the power system; and coupling the voltage value of each said first storage means representative of the highest voltage present of said phase to discharge a third storage means to a voltage value representative of the lowest voltage present on any phase of the power system.
Claim 9
Dependent Claim
102 words
The method as set forth in claim 6, wherein the multi-phase power system comprises a conventional three phase power system in which each phase differs by one third of a cycle, the method further comprising the step of protecting phase reversal of said phases by rotating signals from the first and third phase by substantially ninety degrees and then summing such signals such that a positive voltage signal is produced if the second phase signal as ahead of the first phase signal and a near zero voltage signal is produced if the first phase signal is ahead of the second phase signal.
Claim 10
Dependent Claim
147 words
An input transducer for a multi-phase electrical power system to provide a first signal and a second signal representative of the highest and lowest currents, respectively, of any of the phases of the power system, said input transducer comprising in combination: means for charging a first storage means for each phase to a value representative of the highest current present on said phase; first means for coupling the value of each said first storage means representative of the highest current present for each phase to charge a second storage means to a value representative of the highest current present on any phase of the power system; and second means for coupling the value of each said first storage means representative of the highest current present to discharge a third storage means to a value representative of the lowest current present on any phase of the power system.
Claim 11
Dependent Claim
147 words
An input transducer for a multi-phase electrical power system to provide a first signal and a second signal representative of the highest and lowest currents, respectively, of any of the phases of the power system, said input transducer comprising in combination: means for charging a first storage means for each phase to a value representative of the highest current present on said phase; first means for coupling the value of each said first storage means representative of the highest current present for each phase to charge a second storage means to a value representative of the highest current present on any phase of the power system; and second means for coupling the value of each said first storage means representative of the highest current present to discharge a third storage means to a value representative of the lowest current present on any phase of the power system.
Claim 12
Dependent Claim
98 words
The input transducer as set forth in claim 8, wherein said multi-phase power system comprises a conventional three-phase power system in which each phase differs by one-third of a cycle, said input transducer further comprising a phase reverse detector including means for rotating signals from the first and third phase by substantially ninety degrees and then summing such signals such that a positive voltage signal is produced if the second phase signal is ahead of the first phase signal and a near-zero voltage signal is produced if the first phase signal is ahead of the second phase signal.
Claim 13
Dependent Claim
54 words
The input transducer as set forth in claim 9, wherein each said storage means comprises a capacitor and wherein said second means for coupling said value of each said first storage means comprises a resistive divider connected to a diode allowing said third storage means to discharge through said diode and said resistive divider.
Claim 14
Dependent Claim
35 words
The input transducer as set forth in claim 10, further comprising an input transformer having primary windings connected in a WYE configuration to the three-phase power system and secondary windings connected to said charging means.
Claim 15
Dependent Claim
35 words
The input transducer as set forth in claim 11, further including power supply means connected to each of said phases of said secondary windings of said transformer for providing rectified positive voltage and negative voltage.
Claim 16
Independent Claim
136 words
A method for providing a first signal and a second signal representative of the highest and the lowest currents, respectively, of any of the phases of a multi-phase electrical power system, comprising the steps of: charging a first storage means for each phase to a value representative of the highest current present on such phase; coupling the value of each said first storage means representative of the highest current present for each phase to charge a second storage means to a value representative of the highest current present on any phase of the power system; and coupling the value of each said first storage means representative of the highest current present of said phase to discharge a third storage means to a value representative of the lowest current present on any phase of the power system.
Claim 17
Independent Claim
136 words
A method for providing a first signal and a second signal representative of the highest and the lowest currents, respectively, of any of the phases of a multi-phase electrical power system, comprising the steps of: charging a first storage means for each phase to a value representative of the highest current present on such phase; coupling the value of each said first storage means representative of the highest current present for each phase to charge a second storage means to a value representative of the highest current present on any phase of the power system; and coupling the value of each said first storage means representative of the highest current present of said phase to discharge a third storage means to a value representative of the lowest current present on any phase of the power system.
Claim 18
Dependent Claim
82 words
The method as set forth in claim 13, wherein the multi-phase power system comprises a conventional three phase power system in which each phase differs by one third of a cycle, the method further comprising the step of detecting phase reversal of said phases by rotating signals from the first and third phase by substantially ninety degrees and then summing such signals such that a phase reversal signal is produced if the second phase signal is ahead of the first phase signal.
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1992-04-24 | 1992-10-24 | 1993-04-25 | $2000.00 | Window Closed / Lapsed |
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