GB288776A - Improvements in or relating to the protection of electrical apparatus - Google Patents

Improvements in or relating to the protection of electrical apparatus

Info

Publication number
GB288776A
GB288776A GB458527A GB458527A GB288776A GB 288776 A GB288776 A GB 288776A GB 458527 A GB458527 A GB 458527A GB 458527 A GB458527 A GB 458527A GB 288776 A GB288776 A GB 288776A
Authority
GB
United Kingdom
Prior art keywords
relay
earth
coil
feeders
coils
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
GB458527A
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
General Electric Co PLC
Original Assignee
General Electric Co PLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by General Electric Co PLC filed Critical General Electric Co PLC
Priority to GB458527A priority Critical patent/GB288776A/en
Publication of GB288776A publication Critical patent/GB288776A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02H—EMERGENCY PROTECTIVE CIRCUIT ARRANGEMENTS
    • H02H3/00—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection
    • H02H3/26—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents
    • H02H3/32—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors
    • H02H3/325—Emergency protective circuit arrangements for automatic disconnection directly responsive to an undesired change from normal electric working condition with or without subsequent reconnection ; integrated protection responsive to difference between voltages or between currents; responsive to phase angle between voltages or between currents involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors involving voltage comparison

Landscapes

  • Testing Of Short-Circuits, Discontinuities, Leakage, Or Incorrect Line Connections (AREA)

Abstract

288,776. General Electric Co., Ltd., and Wilson, W. Feb. 18, 1927. Cut-out arrangements.-An isolated electric system such as bus-bars 2, 3 and feeders 4, 5 and 6, 7 is protected against earth faults by a relay comprising differentially-acting coils 56, 59 connected between the busbars 2, 3 and earth 8. Assuming an earth fault develops upon the feeder 5, the potential across coil 57 increases while that across coil 59 decreases, whereupon relay contacts 27, 29 close thus causing a heavy current to flow through feeder 5 and earth 8. As there is not a corresponding increase of current in associated feeder 4, differential relay 10 operates to energize coil 45 of circuit-breaker 11 and thereby isolate the feeders 4, 5. Closure of contacts 27, 29 also short circuits coil 57, and therefore this relay returns to its mid-position and the sound feeders 6, 7 are left in operation. The relay 57, 59 might connect the bus-bar to earth through a resistance or it might directly cause operation of the circuit-breakers. The arrangement can be applied to a three-phase A.C. system by using instead of the coils 57, 59. three coils acting on a steel disc at equallyspaced peripheral points, the disc being supported near its centre on three pins.
GB458527A 1927-02-18 1927-02-18 Improvements in or relating to the protection of electrical apparatus Expired GB288776A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB458527A GB288776A (en) 1927-02-18 1927-02-18 Improvements in or relating to the protection of electrical apparatus

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB458527A GB288776A (en) 1927-02-18 1927-02-18 Improvements in or relating to the protection of electrical apparatus

Publications (1)

Publication Number Publication Date
GB288776A true GB288776A (en) 1928-04-19

Family

ID=9779937

Family Applications (1)

Application Number Title Priority Date Filing Date
GB458527A Expired GB288776A (en) 1927-02-18 1927-02-18 Improvements in or relating to the protection of electrical apparatus

Country Status (1)

Country Link
GB (1) GB288776A (en)

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