US3308345A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical-fault detector for detecting fault currents having an appreciable harmonic content
Assignee: English Electric Co Ltd
•
Filing: 1964-09-02
•
Granted: 1967-03-07
•
Expires: 1984-09-02
Abstract
No abstract record available.
Inventors
- 👤 Warringto Albert Rus Cortlandt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:16
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/26; H02H3/32; H02H3/34; H02H3/347; H02H3/50; H02H3/52
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
131 words
AN ELECTRICAL-FAULT DETECTOR COMPRISING A POWER SUPPLY LINE, SENSING MEANS COUPLED TO SAID POWER SUPPLY LINE FOR DEVELOPING A SIGNAL DEPENDENT ON THE LINE CURRENT, SAID SENSING MEANS COMPRISING A TRANSACTOR HAVING A NON-LINEAR FREQUENCY RESPONSE WHEREBY TO ACCENTUATE THE MAGNITUDE OF THE HIGH FREQUENCY COMPONENTS RELATIVE TO THE LOW FREQUENCY COMPONENTS OF SAID SIGNAL, FILTER MEANS FOR SEPARATING THE FUNDAMENTAL AND LOW HARMONIC FREQUENCY COMPONENTS FROM SAID SIGNAL, CONTROL MEANS RESPONSIVE TO THE REMAINING PART OF SAID SIGNAL AND OPERABLE TO DERIVE A CONTROL SIGNAL THEREFROM, AND DETECTOR MEANS OPERABLE IN RESPONSE TO SAID CONTROL SIGNAL UPON THE MAGNITUDE THEREOF EXCEEDING A PREDETERMINED VALUE WHEREBY TO DETECT ONLY SUCH FAULTS AS PRODUCE A DISTORTED LINE CURRENT HAVING AN APPRECIABLE CONTENT OF HARMONICS OF HIGHER ORDER THAN SAID LOW FREQUENCY COMPONENT.
Claim 2
Dependent Claim
131 words
AN ELECTRICAL-FAULT DETECTOR COMPRISING A POWER SUPPLY LINE, SENSING MEANS COUPLED TO SAID POWER SUPPLY LINE FOR DEVELOPING A SIGNAL DEPENDENT ON THE LINE CURRENT, SAID SENSING MEANS COMPRISING A TRANSACTOR HAVING A NON-LINEAR FREQUENCY RESPONSE WHEREBY TO ACCENTUATE THE MAGNITUDE OF THE HIGH FREQUENCY COMPONENTS RELATIVE TO THE LOW FREQUENCY COMPONENTS OF SAID SIGNAL, FILTER MEANS FOR SEPARATING THE FUNDAMENTAL AND LOW HARMONIC FREQUENCY COMPONENTS FROM SAID SIGNAL, CONTROL MEANS RESPONSIVE TO THE REMAINING PART OF SAID SIGNAL AND OPERABLE TO DERIVE A CONTROL SIGNAL THEREFROM, AND DETECTOR MEANS OPERABLE IN RESPONSE TO SAID CONTROL SIGNAL UPON THE MAGNITUDE THEREOF EXCEEDING A PREDETERMINED VALUE WHEREBY TO DETECT ONLY SUCH FAULTS AS PRODUCE A DISTORTED LINE CURRENT HAVING AN APPRECIABLE CONTENT OF HARMONICS OF HIGHER ORDER THAN SAID LOW FREQUENCY COMPONENT.
References Cited (Backward Citations)
US1539834A
Cited
US1759952A
Cited
CH139304A
Cited
CH145544A
Cited
US2474290A
Cited
US2863100A
Cited
US3015774A
Cited
US3165671A
Cited
US3223889A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1970-03-06 | 1970-09-05 | 1971-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1974-03-06 | 1974-09-05 | 1975-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1978-03-06 | 1978-09-05 | 1979-03-07 | $7700.00 | Window Closed / Lapsed |