US3775683A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical power measuring device
Assignee: SPX Technologies Inc
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Filing: 1972-05-10
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Granted: 1973-11-27
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Expires: 1992-05-10
Abstract
Abstract An electrical power measuring device is for use with electrical quantities such as alternating voltage and current and has a voltage integrator connected through an impedance across a selected source of alternating voltage and supplied with a local current of one polarity and of a predetermined value and also supplied with a local current of the opposite polarity and of substantially twice the predetermined value. A level detector responsive to voltage level in the integrator is effective through a pulse mechanism to switch one of the local currents off and on and simultaneously to switch a circuit extending between the selected current source and an output measuring or actuating device. Various amplifying, storage and filtering devices are used.
Inventors
- 👤 K Barta
- 👤 W Pritchett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 19:57
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/12; G06G7/16; G06G7/161; G01; G01R; G01R21/00
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
343 words
An electrical power measuring device for use with a selected alternating voltage source and a selected current source comprising a first transformer having a primary winding and a secondary winding, an impedance, means for connecting said primary winding of said first transformer and said impedance in series across said voltage source, and integrator having an input terminal and an output terminal, means for connecting said secondary winding of said first transformer to ground and to said integrator input terminal, a first source of local current of one polarity and of predetermined value, means for connecting said first source to said input terminal of said integrator, a second source of local current of opposite polarity and of substantially twice said predetermined value, means for connecting said second source to said input terminal of said integrator, a circuit common, a switch effective in one condition to connect said second source to said circuit common and in another condition to isolate said second source from said circuit common, a level detector, means for connecting the output terminal of said integrator to said level detector whereby a voltage of a predetermined level at said output terminal produces a pulse from said level detector, a storage element, means for supplying pulses from said level detector to said storage element, meaNs controlled by said storage element for alternating said switch between said one condition and said other condition, a reversing switch having an input and an output, means joining said input to said storage device, means joining said output to said measurement device, a second transformer having a primary winding and a secondary winding, means for connecting said primary winding of said second transformer across said selected current source, means for connecting said secondary winding of said second transformer across said reversing switch whereby the ends of said second winding of said second transformer are alternately connected to circuit common, a center tap in said secondary winding of said second transformer, and means for connecting said center tap through said reversing switch to the output of said reversing switch.
Claim 2
Dependent Claim
343 words
An electrical power measuring device for use with a selected alternating voltage source and a selected current source comprising a first transformer having a primary winding and a secondary winding, an impedance, means for connecting said primary winding of said first transformer and said impedance in series across said voltage source, and integrator having an input terminal and an output terminal, means for connecting said secondary winding of said first transformer to ground and to said integrator input terminal, a first source of local current of one polarity and of predetermined value, means for connecting said first source to said input terminal of said integrator, a second source of local current of opposite polarity and of substantially twice said predetermined value, means for connecting said second source to said input terminal of said integrator, a circuit common, a switch effective in one condition to connect said second source to said circuit common and in another condition to isolate said second source from said circuit common, a level detector, means for connecting the output terminal of said integrator to said level detector whereby a voltage of a predetermined level at said output terminal produces a pulse from said level detector, a storage element, means for supplying pulses from said level detector to said storage element, meaNs controlled by said storage element for alternating said switch between said one condition and said other condition, a reversing switch having an input and an output, means joining said input to said storage device, means joining said output to said measurement device, a second transformer having a primary winding and a secondary winding, means for connecting said primary winding of said second transformer across said selected current source, means for connecting said secondary winding of said second transformer across said reversing switch whereby the ends of said second winding of said second transformer are alternately connected to circuit common, a center tap in said secondary winding of said second transformer, and means for connecting said center tap through said reversing switch to the output of said reversing switch.
Claim 3
Dependent Claim
20 words
A device as in claim 1 in which said integrator includes a capacitor and an inverting amplifier connected in parallel.
Claim 4
Dependent Claim
25 words
A device as in claim 1 in which said lever detector is responsive to voltage at the output of said integrator over a time base.
Claim 5
Dependent Claim
24 words
A device as in claim 1 in which said pulse is effective simultaneously to change the condition of said switch and said reversing switch.
References Cited (Backward Citations)
US3610910A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-26 | 1977-05-28 | 1977-11-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-26 | 1981-05-28 | 1981-11-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-26 | 1985-05-28 | 1985-11-27 | $7700.00 | Window Closed / Lapsed |