US3852660A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit breaker fault simulator
Assignee: Westinghouse Electric Corp
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Filing: 1973-09-28
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Granted: 1974-12-03
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Expires: 1993-09-28
Abstract
Abstract A relatively small, electrical device which provides voltage signals on two output lines thereof. The output lines are adapted to be connected by way of a suitable plug to a set of special input terminals on a molded case circuit breaker. The simulator is energized by standard 120 volt, 60 hz. power. The signals from the output terminals of the simulator are provided to the static trip circuit of the circuit breaker. The input connections are so arranged as not to interfere with the overload sensing devices of the circuit breaker being tested. Consequently, the circuit breaker need not be disconnected while testing. By moving a selector switch either a high level or low level signals may be applied from the simulator to the static trip circuit. The high level signal corresponds to an overload condition which would normally cause an instantaneous trip of the circuit breaker. This signal is timed or limited to be removed from the input of the trip circuit after a short period of time. This prevents the trip circuit from being damaged by the signal. Low level signals may be applied which simulates that kind of overload condition which would normally cause the circuit breaker to trip after a predetermined delay.
Inventors
- 👤 A Maier
- 👤 A Shimp
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 17:58
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/02; H02H3/04; H02H3/044
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
235 words
A fault simulator for a trip circuit of a circuit interrupter, where said trip circuit is electrically connected to a sensor and where said sensor monitors the electrical current flowing in an electrical conductor protected by said circuit interrupter to thereby provide a signal to said trip circuit to thereby cause said trip circuit to actuate said circuit interrupter to act to protect said conductor from the effects of said current when said current attains a predetermined value and after a predetermined period of time which time is related to the amount of electrical current monitored by said sensors, comprising: A. first means additional to said sensor actuable for providing a first simulating signal to said trip circuit at any desired time and regardless of the value of current flowing in said conductor, said latter signal simulating said signal from said sensor when said value of current flowing in said conductor is substantially larger than said predetermined value; B. second means additional to said sensor actuable for providing a second simulating signal to said trip circuit at any desired time and regardless of the value of current flowing in said conductor, said latter signal simulating said signal from said sensor when said value of current flowing in said conductor is larger but not substantially larger than said predetermined value; and C. third means for interconnecting said first and said second means with said trip circuit.
Claim 2
Dependent Claim
235 words
A fault simulator for a trip circuit of a circuit interrupter, where said trip circuit is electrically connected to a sensor and where said sensor monitors the electrical current flowing in an electrical conductor protected by said circuit interrupter to thereby provide a signal to said trip circuit to thereby cause said trip circuit to actuate said circuit interrupter to act to protect said conductor from the effects of said current when said current attains a predetermined value and after a predetermined period of time which time is related to the amount of electrical current monitored by said sensors, comprising: A. first means additional to said sensor actuable for providing a first simulating signal to said trip circuit at any desired time and regardless of the value of current flowing in said conductor, said latter signal simulating said signal from said sensor when said value of current flowing in said conductor is substantially larger than said predetermined value; B. second means additional to said sensor actuable for providing a second simulating signal to said trip circuit at any desired time and regardless of the value of current flowing in said conductor, said latter signal simulating said signal from said sensor when said value of current flowing in said conductor is larger but not substantially larger than said predetermined value; and C. third means for interconnecting said first and said second means with said trip circuit.
Claim 3
Dependent Claim
30 words
The combination as claimed in claim 1, comprising a fourth means for selectively choosing which of said first simulating or said second simulating means is provided to said trip circuit.
Claim 4
Dependent Claim
62 words
second means additional to said sensor means actuable for providing a second simulating signal to said trip circuit at any desired time and regardless of the value of current flowing in said conductor, said latter signal simulating said signal from said sensor when said value of current flowing in said conductor is larger but not substantially larger than said predeteRmined value; and
Claim 5
Dependent Claim
62 words
second means additional to said sensor means actuable for providing a second simulating signal to said trip circuit at any desired time and regardless of the value of current flowing in said conductor, said latter signal simulating said signal from said sensor when said value of current flowing in said conductor is larger but not substantially larger than said predeteRmined value; and
Claim 6
Dependent Claim
17 words
The combination as claimed in claim 1 wherein said trip circuit comprises a solid state trip circuit.
Claim 7
Dependent Claim
14 words
third means for interconnecting said first and said second means with said trip circuits.
Claim 8
Dependent Claim
14 words
third means for interconnecting said first and said second means with said trip circuits.
Claim 9
Dependent Claim
33 words
The combination as claimed in claim 1 wherein said circuit interrupter comprises a circuit breaker with separable main contacts, said separable main contacts being actuated to the open state to protect said conductor.
Claim 10
Dependent Claim
20 words
The combination as claimed in claim 1 wherein said first simulating signal and said second simulating signal are electrical signals.
Claim 11
Dependent Claim
62 words
The combination as claimed in claim 1 wherein said first means comprises means for removing said first simulating signal from said trip circuit a predetermined time after the application thereof which time is related to the capability of said trip circuit to be exposed to said first simulating signal without being damaged to the state of inoperability for the intended purpose thereof.
Claim 12
Dependent Claim
200 words
The combination as claimed in claim 1 wherein said first means comprises: A. a source of electrical current; B. first resistant means; C. first capacitive means, said first resistive means and said capacitive means being interconnected electrically in circuit relationship to form a charging network for said capacitive means with a portion of said electrical current from said source of said electrical current to a predetermined voltage value during a predetermined period of time; D. voltage sensitive relay means having movable contacts, said relay means being connected in circuit relationship with said capacitive means and energizable by the voltage level across said capacitive means to open and close said relay means movable contacts; and E. electrical interconnecting means comprising said movable contacts of said relay means and connected between said source of electrical current and said trip circuit to supply said first simulating signal in the form of the remaining portion of electrical current from said source of current to said trip circuit when said simulator is actuated for that purpose, said relay contacts opening and thus presenting further application of said simulating signals to said trip circuit when said capacitive means has been charged to said predetermined voltage value.
Claim 13
Dependent Claim
124 words
The combination as claimed in claim 1 wherein said first means comprises: A. a source of electrical current; and B. a temperature sensitive first resistive means which has the characteristic of increasing in resistance value as the temperature therein increases due to the continued flow of electrical current therethrough, said first resistive means interconnecting said source of current and said trip circuit to supply said first simulating signal in the form of electrical current from said source of current when said simulator is actuated for that purpose, said current being limited a predetermined time thereafter to thereby substantially limit the flow of current therethrough in response to the rise of temperature therein to essentially prevent simulating signal from further substantially energizing said trip circuit.
Claim 14
Dependent Claim
128 words
Circuit breaker apparatus, comprising: A. a circuit breaker having separable main contacts operable to open and close on an electrical conductor to be protected thereby, opening means operable for actuating said contacts to the open position; B. a trip circuit interconnected with said opening means for causing operation thereof; C. sensor means interconnected with said trip circuit and disposed to monitor the electrical current in said electrical conductor, said sensor means providing a signal of said trip circuit when said current in said conductor attains a predetermined value, said trip circuit causing the opening of said main contacts after a predetermined period of time which time is related to the amount of said electrical current in said conductor as monitored by said sensor; D. a fault simulator, comprising:
Claim 15
Dependent Claim
128 words
Circuit breaker apparatus, comprising: A. a circuit breaker having separable main contacts operable to open and close on an electrical conductor to be protected thereby, opening means operable for actuating said contacts to the open position; B. a trip circuit interconnected with said opening means for causing operation thereof; C. sensor means interconnected with said trip circuit and disposed to monitor the electrical current in said electrical conductor, said sensor means providing a signal of said trip circuit when said current in said conductor attains a predetermined value, said trip circuit causing the opening of said main contacts after a predetermined period of time which time is related to the amount of said electrical current in said conductor as monitored by said sensor; D. a fault simulator, comprising:
Claim 16
Dependent Claim
32 words
The combination as claimed in claim 9 comprising a fourth means for selectively choosing which of either said first simulating means or said second simulating means is provided to said trip circuit.
Claim 17
Dependent Claim
17 words
The combination as claimed in claim 9 wherein said trip circuit comprises a solid state trip circuit.
Claim 18
Dependent Claim
33 words
The combination as claimed in claim 9 wherein said circuit interrupter comprises a circuit breaker with separable main contacts, said separable main contacts being actuated to the open condition to protect said conductor.
Claim 19
Dependent Claim
20 words
The combination as claimed in claim 9 wherein said first simulating signal and said second simulating signal are electrical signals.
Claim 20
Dependent Claim
62 words
The combination as claimed in claim 9 wherein said first means comprises means for removing said first simulating signal from said trip circuit a predetermined time after the application thereof which time is related to the capability of said trip circuit to be exposed to said first simulating signal without being damaged to the state of inoperability for the intended purpose thereof.
Claim 21
Dependent Claim
125 words
The combination as claimed in claim 9, wherein said first means comprises: A. a source of electrical current; and B. a temperature sensitive first resistive means which has the characteristic of increasing in resistance value as the temperature therein increases due to the continued flow of electrical current therethrough, said first resistive means interconnecting said source of current and said trip circuit to supply said first simulating signal in the form of electrical current from said source of current when said simulator is actuated for that purpose, said current being limited a predetermined time thereafter to thereby substantially limit the flow of current therethrough in response to the rise of temperature therein to essentially prevent said simulating signal from further substantially energizing said trip circuit.
Claim 22
Dependent Claim
204 words
The combination as claimed in claim 9 wherein said first means comprises: A. a source of direct electrical current; B. first resistive means; C. first capacitive means, said first resistive means and said capacitive means being interconnected in electrical circuit relationships to form a charging network for charging said capacitive means with a portion of said electrical current from said source of electrical current to a predetermined voltage value during a predetermined period of time; D. voltage sensitive relay means having movable relay contacts, said relay means having movable relay contacts, said relay means being connected in circuit relationship with said capacitive means and energized by the voltage level across said capacitive means to open and close said movable relay contacts; and E. electrical interconnecting means comprising said movable relay contacts interconnected between said source of electrical current and said trip circuit to supply said first simulating signal in the form of the remaining portion of electrical current from said source of current to said trip circuit when said simulator is actuated for that purpose, said relay contacts opening and thus preventing further application of said simulating signal to said trip circuit when said capacitive means has been charged to said predetermined voltage value.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-12-02 | 1978-06-03 | 1978-12-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-12-02 | 1982-06-03 | 1982-12-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-12-02 | 1986-06-03 | 1986-12-03 | $7700.00 | Window Closed / Lapsed |