GB288776A - Improvements in or relating to the protection of electrical apparatus - Google Patents
Improvements in or relating to the protection of electrical apparatusInfo
- 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
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.
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) |
-
1927
- 1927-02-18 GB GB458527A patent/GB288776A/en not_active Expired
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US2554598A (en) | Safety system for portable electrical apparatus | |
GB1061064A (en) | Electric switch installations | |
GB288776A (en) | Improvements in or relating to the protection of electrical apparatus | |
US2320123A (en) | Protection of alternating current electric systems | |
GB858638A (en) | Improvements in or relating to protective relaying systems | |
GB380808A (en) | Improvements in or relating to protective cut-out systems | |
US1554704A (en) | Protective system | |
GB218938A (en) | Improvements in and relating to a protective device for an alternating current system | |
US1988121A (en) | Protective means for delta connected transmission lines | |
US2027189A (en) | Control and protection of electric circuits | |
US2258248A (en) | Protection of alternating current electric systems | |
US1718516A (en) | Automatic reclosing circuit-breaker system | |
US1776132A (en) | Protective arrangement | |
US2258246A (en) | Protection of alternating current electric systems | |
GB1322586A (en) | Harmonic filter protection means | |
GB535446A (en) | Improvements in and relating to earth leakage protective systems | |
GB353732A (en) | Improvements in or relating to electrical protective relay systems | |
US1752852A (en) | Safety system | |
GB268758A (en) | Improvements in and relating to electric circuit protection systems and apparatus therefor | |
GB291155A (en) | Improvements in or relating to protective gear for alternating-current distribution systems | |
GB553260A (en) | Improvements in earth leakage electric protective arrangements | |
GB269983A (en) | Improvements in or relating to protective arrangements for duplicate feeder electricsystems | |
GB1043595A (en) | Overheating and earth-fault protection system for electric motors and transformers | |
GB250494A (en) | Improvements in or relating to protective arrangements for electric distribution or supply systems | |
GB265952A (en) | Improvements in and relating to protective systems for electric distribution systems |