US3869649A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical protective panel assembly with sensitive ground fault protecting means
Assignee: General Electric Co
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Filing: 1973-04-13
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Granted: 1975-03-04
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Expires: 1993-04-13
Abstract
Abstract An electrical protective circuit, including at least one and preferably a number of automatically operable circuit protective devices and means for connecting the circuit protective devices to corresponding power consuming loads. The protective circuit includes means for connecting the return or neutral conductors from the respective power consuming loads to one side of an electrical power source, which side is grounded at a point between the protective device and the power source. Means is included for detecting the presence of a ground fault on any one of the return or ''''neutral'''' conductors which occurs at a point between the corresponding protective device and the load which it protects. The purpose of detecting the presence of such a neutral ground fault is primarily to render more accurate and reliable the operation of means for detecting and protecting against ground faults from the ungrounded or ''''high'''' side of the line to ground since such neutral grounding can render the detection of minute ground currents from the ''''high'''' side of the line to ground unreliable. This is particularly important in connection with ground fault detecting devices which are used for protecting people from injury or death by electric shock. In one form of the invention a common terminal strip is provided for connecting together a plurality of return or neutral lines from a plurality of electrical loads. Means is also provided for inducing a voltage in the circuit in series relation with each and all of the return or neutral lines. On the occurrence of a fault between any return or neutral line and ground, current flows in the loop comprising the respective return or neutral conductor, the normal ground connection, ground, the ground fault, back to the return or neutral conductor. The presence of current in this path acts to cause the corresponding breaker to open. An important feature of the invention is that it permits use of a single induced voltage to serve the needs of a number of circuits.
Inventors
- 👤 Jr Charles F Hobson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 01:33
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/26; H02H3/32; H02H3/33; H02H3/331; H02H3/16; H02H3/17
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
249 words
An electrical protective circuit for supplying power to an electrical load and including means responsive to the occurrence of unintended ground connection between at least one load supplying conductor and ground comprising: a. a support; b. an electrical circuit protective device supported on said support and having a first terminal for connection to one side of an electrical power source and a second terminal for connection to an outgoing conductor for supplying power to a remote power consuming load, said device including means for interrupting current to such outgoing conductor; c. return conductor electrical connecting means supported on said support for connection to a return conductor from such power consuming load; d. terminal connecting means supported on said support for connection to the side of such power source opposite from such one side, and conductor means connecting said terminal connecting means to said return conductor connecting means; e. voltage inducing means for inducing a voltage in said conductor means; f. ground connecting means connecting said conductor means to ground at a point closer to said terminal connecting means than the point at which said voltage inducing means induces a voltage in said conductor means; g. current detecting means associated with said ground connecting means for detecting current therein, and for developing a signal in response thereto; h. means connected between said current detecting and said circuit interrupting device for causing automatic opening of said circuit interrupting device upon the generation of a predetermined signal by said current detecting means.
Claim 2
Dependent Claim
249 words
An electrical protective circuit for supplying power to an electrical load and including means responsive to the occurrence of unintended ground connection between at least one load supplying conductor and ground comprising: a. a support; b. an electrical circuit protective device supported on said support and having a first terminal for connection to one side of an electrical power source and a second terminal for connection to an outgoing conductor for supplying power to a remote power consuming load, said device including means for interrupting current to such outgoing conductor; c. return conductor electrical connecting means supported on said support for connection to a return conductor from such power consuming load; d. terminal connecting means supported on said support for connection to the side of such power source opposite from such one side, and conductor means connecting said terminal connecting means to said return conductor connecting means; e. voltage inducing means for inducing a voltage in said conductor means; f. ground connecting means connecting said conductor means to ground at a point closer to said terminal connecting means than the point at which said voltage inducing means induces a voltage in said conductor means; g. current detecting means associated with said ground connecting means for detecting current therein, and for developing a signal in response thereto; h. means connected between said current detecting and said circuit interrupting device for causing automatic opening of said circuit interrupting device upon the generation of a predetermined signal by said current detecting means.
Claim 3
Dependent Claim
70 words
An electrical protective circuit as set forth in claim 1 wherein said protective circUit includes more than one circuit interrupting device and wherein said return conductor connecting means includes means for connection to the return conductors of a plurality of said interrupting devices and wherein said circuit also includes means for causing automatic opening of all of said devices having their return conductors connected to said return conductor connector means.
Claim 4
Dependent Claim
191 words
An electrical protective panel assemblly comprising: a. an enclosure; b. a plurality of automatic circuit protective devices in said enclosure; c. a neutral bar in said enclosure for receiving return power conductors from a plurality of electrical power consuming loads; d. a first primary electrical connector in said enclosure for connection to input terminals of such electrical devices; e. a second primary electrical connector in said enclosure; f. conductor means connecting said neutral bar to said second primary electrical connector; g. voltage inducing means in said enclosure for inducing a voltage in said conductor means between said neutral bar and said second primary electrical connector; h. grounding conductor means connecting said conductor means to ground on the line side of said voltage inducing means; i. current sensing means associated with said grounding conductor means, said current sensing means generating an electrical signal upon the flow of current through said grounding conductor means; j. whereby said electrical signal generating means may be utilized to cause automatic opening of at least one or more of such protective devices providing power to power consuming loads having their return conductors connected to said neutral bar.
Claim 5
Dependent Claim
191 words
An electrical protective panel assemblly comprising: a. an enclosure; b. a plurality of automatic circuit protective devices in said enclosure; c. a neutral bar in said enclosure for receiving return power conductors from a plurality of electrical power consuming loads; d. a first primary electrical connector in said enclosure for connection to input terminals of such electrical devices; e. a second primary electrical connector in said enclosure; f. conductor means connecting said neutral bar to said second primary electrical connector; g. voltage inducing means in said enclosure for inducing a voltage in said conductor means between said neutral bar and said second primary electrical connector; h. grounding conductor means connecting said conductor means to ground on the line side of said voltage inducing means; i. current sensing means associated with said grounding conductor means, said current sensing means generating an electrical signal upon the flow of current through said grounding conductor means; j. whereby said electrical signal generating means may be utilized to cause automatic opening of at least one or more of such protective devices providing power to power consuming loads having their return conductors connected to said neutral bar.
Claim 6
Dependent Claim
320 words
An electrical protective panel assembly comprising, in combination: a. at least two electrical power source terminals for connection to an external source of electrical power; b. means connecting a plurality of first electrical circuit protective devices to one of said electric power source terminals, each of said first devices having ground fault circuit interrupting capability in form of means for sensing an imbalance in the currents flowing to and returning from remotely connected loads; c. means connecting a second plurality of electrical circuit protective devices to said one electric power source terminal, said second devices lacking ground fault circuit interrupting capability; d. means connecting the other of said electric power source terminals to ground; e. first and second connector bars, said second connector bar being electrically connected to said grounded power source terminal; f. an outgoing conductor connecting each said first protective device to a different electrical load and each said second protective device to a different second electrical load; g. a return conductor connecting each said first electrical load to the associated one of said first protective devices and each said second electrical load to said second terminal bar; h. conductor means connecting said first terminal bar to each of said first protective devices and in series with said return conductors connected from said first electrical loads; and i. electrical signal injecting means including a transformer core and a multi-turn secondary winding connected in series between first and second terminal bars, said signal injecting means operative to create an electrical signal voltage common to said return conductors connected from said first loads; j. whereby inadvertent grounding of any one of said return conductors connected to said first loads produces a complete circuit loop not including said power supply in which said signal voltage causes a signal current to circulate, thereby to produce a current imbalance sensible by the one of said first devices connected to said grounded return conductor.
Claim 7
Dependent Claim
320 words
An electrical protective panel assembly comprising, in combination: a. at least two electrical power source terminals for connection to an external source of electrical power; b. means connecting a plurality of first electrical circuit protective devices to one of said electric power source terminals, each of said first devices having ground fault circuit interrupting capability in form of means for sensing an imbalance in the currents flowing to and returning from remotely connected loads; c. means connecting a second plurality of electrical circuit protective devices to said one electric power source terminal, said second devices lacking ground fault circuit interrupting capability; d. means connecting the other of said electric power source terminals to ground; e. first and second connector bars, said second connector bar being electrically connected to said grounded power source terminal; f. an outgoing conductor connecting each said first protective device to a different electrical load and each said second protective device to a different second electrical load; g. a return conductor connecting each said first electrical load to the associated one of said first protective devices and each said second electrical load to said second terminal bar; h. conductor means connecting said first terminal bar to each of said first protective devices and in series with said return conductors connected from said first electrical loads; and i. electrical signal injecting means including a transformer core and a multi-turn secondary winding connected in series between first and second terminal bars, said signal injecting means operative to create an electrical signal voltage common to said return conductors connected from said first loads; j. whereby inadvertent grounding of any one of said return conductors connected to said first loads produces a complete circuit loop not including said power supply in which said signal voltage causes a signal current to circulate, thereby to produce a current imbalance sensible by the one of said first devices connected to said grounded return conductor.
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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) | 1978-03-03 | 1978-09-02 | 1979-03-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-03 | 1982-09-02 | 1983-03-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-03 | 1986-09-02 | 1987-03-04 | $7700.00 | Window Closed / Lapsed |