US4539520A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Remote current detector
Assignee: BRIDGES ELECTRIC Inc
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Filing: 1983-07-13
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Granted: 1985-09-03
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Expires: 2003-07-13
Abstract
Abstract A remote current sensor for use in a fault detector for an electrical transmission system. The remote current sensor includes a Hall effect transducer for measuring the magnetic field surrounding a conductor of the transmission system to thereby monitor the currents flowing through the conductor. The transducer is positioned between a pair of tapered pole pieces for concentrating low density magnetic flux in the air into a high density magnetic flux focused onto the transducer. The pole pieces enable the sensors to be positioned a distance from the conductor which is greater than the electrical arcing distance so as to allow use of the air gap between the conductor and sensor as insulation.
Inventors
- 👤 Joseph R. McBride
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 11:03
CPC Classifications
G; G01; G01R; G01R15/00; G01R15/14; G01R15/20; G01R15/202; G01R31/00; G01R31/50; G01R31/58
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
156 words
A remote current sensor for monitoring the current flowing through a conductor, said sensor to be positioned in a magnetic field surrounding the conductor, comprising: a Hall effect transducer for measuring the magnetic field surrounding said conductor; a pair of tapered pole pieces with said transducer positioned therebetween, each of said pole pieces being made of a ferromagnetic material and having a wide cross sectional area at one end to pick up a low density magnetic flux in the air and a small cross sectional area at the opposite end adjacent to the transducer to concentrate said low density magnetic flux into a high density magnetic flux focused onto the transducer, the transducer and pole pieces being positioned at a location removed from the conductor greater than the electric arcing distance for the voltage at which the conductor is normally operated; and a grounded aluminum housing for said sensor to shield the sensor from electric fields.
Claim 2
Dependent Claim
156 words
A remote current sensor for monitoring the current flowing through a conductor, said sensor to be positioned in a magnetic field surrounding the conductor, comprising: a Hall effect transducer for measuring the magnetic field surrounding said conductor; a pair of tapered pole pieces with said transducer positioned therebetween, each of said pole pieces being made of a ferromagnetic material and having a wide cross sectional area at one end to pick up a low density magnetic flux in the air and a small cross sectional area at the opposite end adjacent to the transducer to concentrate said low density magnetic flux into a high density magnetic flux focused onto the transducer, the transducer and pole pieces being positioned at a location removed from the conductor greater than the electric arcing distance for the voltage at which the conductor is normally operated; and a grounded aluminum housing for said sensor to shield the sensor from electric fields.
Claim 3
Dependent Claim
37 words
The remote current sensor of claim 1 further including a sleeve rigidly supporting said pole pieces so that the magnetic field picked up by the pole pieces is focused directly onto a sensitive area of said transducer.
Claim 4
Dependent Claim
16 words
The remote current sensor of claim 2 wherein said sleeve is of an electrically insulating material.
References Cited (Backward Citations)
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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) | 1988-09-02 | 1989-03-04 | 1989-09-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-02 | 1993-03-04 | 1993-09-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-02 | 1997-03-04 | 1997-09-03 | $7700.00 | Window Closed / Lapsed |