ALTERNATING CURRENT FAULT INDICATING MEANS
First Claim
1. Means responsive to flow of alternating fault current in and high voltage energization of a conductor comprising:
- means for responding to current flow in said conductor, capacitor means, reset rectifier means, conductive circuit means for directly interconnecting said capacitor means and said conductor through said rectifier means to charge said capacitor means to a unidirectional voltage corresponding to the alternating energizing voltage of said conductor, and fault indicating means remote from said conductor including;
a target, a magnetic core, a trip winding on said magnetic core circuit means interconnecting said trip winding and said current flow responsive means for moving said target from a non-indicating position to a fault indicating position in response to flow of fault current in said conductor, and a reset winding on said magnetic core connected to be energized from said capacitor means for moving said target from said fault indicating position to said non-indicating position on application of energizing voltage to said conductor and current flow therein less than fault current flow.
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Accused Products
Abstract
Fault current flow in an alternating current carrying conductor is shown by operation of a target to fault indicating position from which it is restored in response to the energizing voltage of the conductor. A C-shaped magnetic core embraces the conductor and has a winding thereon the output of which is rectified and, when it reaches a predetermined value, is applied to a trip winding of a fault indicator to operate the target. A reset winding of the fault indicator is energized from a capacitor that is charged from the conductor voltage a source of which may be obtained from a capacitor plate embedded in the insulation of a conductor terminator. In a modification alternating current is applied to the trip winding to demagnetize the magnetic core of the indicator and allows a permanent magnet to bias the target to fault indicating position. Other modifications include energization of the reset circuit from the secondary winding of a distribution transformer, provision for magnetizing the distal ends of a U-shaped yoke embracing a conductor carrying fault current, and application of the yoke to the conductor of a pad mounted switching arrangement for a transformer.
50 Citations
16 Claims
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1. Means responsive to flow of alternating fault current in and high voltage energization of a conductor comprising:
- means for responding to current flow in said conductor, capacitor means, reset rectifier means, conductive circuit means for directly interconnecting said capacitor means and said conductor through said rectifier means to charge said capacitor means to a unidirectional voltage corresponding to the alternating energizing voltage of said conductor, and fault indicating means remote from said conductor including;
a target, a magnetic core, a trip winding on said magnetic core circuit means interconnecting said trip winding and said current flow responsive means for moving said target from a non-indicating position to a fault indicating position in response to flow of fault current in said conductor, and a reset winding on said magnetic core connected to be energized from said capacitor means for moving said target from said fault indicating position to said non-indicating position on application of energizing voltage to said conductor and current flow therein less than fault current flow.
- means for responding to current flow in said conductor, capacitor means, reset rectifier means, conductive circuit means for directly interconnecting said capacitor means and said conductor through said rectifier means to charge said capacitor means to a unidirectional voltage corresponding to the alternating energizing voltage of said conductor, and fault indicating means remote from said conductor including;
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2. Current and voltage responsive means according to claim 1 wherein said means for responding to current flow in said conductor includes a magnetic core for linking said conductor and a current winding linking the last mentioned magnetic core.
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3. Current and voltage responsive means according to claim 2 wherein rectifier means interconnects said current winding and said trip winding through a zener diode rendered conducting on flow of fault current in said conductor, and voltage sensitive switch means connected between said capacitor means and said reset winding is rendered conducting when said capacitor means is charged to said unidirectional voltage.
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4. Current and voltage responsive means according to claim 1 wherein rectifier means interconnects said current flow responsive means and said trip winding through a zener diode rendered conducting on flow of fault current in said conductor.
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5. Current and voltage responsive means according to claim 4 wherein voltage sensitive switch means connected between said rectifier means and said trip winding is rendered conducting on flow of fault current in said conductor.
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6. Current and voltage responsive means according to claim 1 wherein said trip winding is energized with alternating current, permanent magnet means connected to said target is responsive to the magnetic field from said reset winding, and stationary permanent magnet means react with said target permanent magnet means to shift said target to fault indicating position on flow of fault current in said conductor and demagnetization of said magnetic core.
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7. Current and voltage responsive means according to cLaim 1 wherein voltage sensitive switch means connected between said capacitor means and said reset winding is rendered conducting when said capacitor means is charged to said unidirectional voltage.
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8. Current and voltage responsive means according to claim 1 wherein said conductive circuit means includes a capacitor plate capacitively coupled to said conductor.
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9. Current and voltage responsive means according to claim 8 wherein said conductor is enclosed in insulator terminator means, and said capacitor plate is embedded in the insulation of said terminator means.
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10. Means responsive to flow of alternating fault current in and energization of a conductor comprising:
- means responsive to flow of current in said conductor, a transformer including a primary winding connected for energization to said conductor and a secondary winding, capacitor means, reset rectifier means connected for energization to said secondary winding to charge said capacitor to a unidirectional voltage corresponding to the voltage of said secondary winding, and fault indicating means including;
trip means operated by said current responsive means on flow of fault current in said conductor, and reset winding means connected to be energized from said capacitor means on application of energizing voltage to said conductor accompanied by energization of said secondary winding.
- means responsive to flow of current in said conductor, a transformer including a primary winding connected for energization to said conductor and a secondary winding, capacitor means, reset rectifier means connected for energization to said secondary winding to charge said capacitor to a unidirectional voltage corresponding to the voltage of said secondary winding, and fault indicating means including;
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11. Fault current and conductor energization responsive means according to claim 10 wherein said means for responding to current flow in said conductor includes a magnetic core for linking said conductor and a current winding linking said magnetic core.
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12. Fault current and conductor energization responsive means according to claim 10 wherein voltage sensitive switch means connected between said capacitor means and said reset winding means is rendered conducting when said capacitor means is charged to said unidirectional voltage.
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13. Fault current and conductor energization responsive means according to claim 10 wherein disconnecting switches connect said conductor in a loop circuit.
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14. Means responsive to flow of alternating fault current in and energization of a conductor comprising:
- means responsive to flow of current in said conductor including a demagnetizable magnetic core embracing said conductor, a transformer including a primary winding connected for energization to said conductor and a secondary winding, capacitor means, reset rectifier means connected for energization to said secondary winding to charge said capacitor to a unidirectional voltage corresponding to the voltage of said secondary winding, and fault indicating means including;
trip means operated by said current responsive means on flow of fault current in said conductor, and reset winding means mounted on said magnetic core and connected to be energized from said capacitor means on application of energizing voltage to said conductor accompanied by energization of said secondary winding after demagnetization of said magnetic core by flow of fault current in said conductor.
- means responsive to flow of current in said conductor including a demagnetizable magnetic core embracing said conductor, a transformer including a primary winding connected for energization to said conductor and a secondary winding, capacitor means, reset rectifier means connected for energization to said secondary winding to charge said capacitor to a unidirectional voltage corresponding to the voltage of said secondary winding, and fault indicating means including;
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15. Fault current and conductor energization responsive means according to claim 14 wherein voltage sensitive switch means connected between said capacitor means and said reset winding means is rendered conducting when said capacitor means is charged to said unidirectional voltage.
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16. Fault current and conductor energization responsive means according to claim 15 wherein said magnetic core provides a pair of opposite poles, a stationary permanent magnet has poles adjacent unlike poles of said magnetic core, and a pivotable permanent magnet adjacent said stationary permanent magnet takes up a normal position when the magnetic field from said poles of said magnetic core is greater than the magnetic field from said poles of said permanent magnet and a fault indicating position when said magnetic core is demagnetized by flow of fault current in said conductor.
Specification