GB973501A - Protection circuit for use with multi-phase a.c. systems - Google Patents

Protection circuit for use with multi-phase a.c. systems

Info

Publication number
GB973501A
GB973501A GB1782260A GB1782260A GB973501A GB 973501 A GB973501 A GB 973501A GB 1782260 A GB1782260 A GB 1782260A GB 1782260 A GB1782260 A GB 1782260A GB 973501 A GB973501 A GB 973501A
Authority
GB
United Kingdom
Prior art keywords
capacitor
machine
systems
phase
protection circuit
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
GB1782260A
Inventor
Kenneth Davy
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.)
Lucas Support Services Ltd
Original Assignee
Rotax Ltd
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 Rotax Ltd filed Critical Rotax Ltd
Priority to GB1782260A priority Critical patent/GB973501A/en
Publication of GB973501A publication Critical patent/GB973501A/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
    • H02H3/08—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 excess current
    • H02H3/10—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 excess current additionally responsive to some other abnormal electrical conditions

Landscapes

  • Protection Of Generators And Motors (AREA)
  • Emergency Protection Circuit Devices (AREA)
  • Protection Of Static Devices (AREA)

Abstract

973,501. Semi-conductor relay circuits. ROTAX Ltd. May 15, 1961 [May 20, 1960], No. 17822/60. Heading H3T. [Also in Division H2] In a polyphase overload protective arrangement, when the highest phase current exceeds a predetermined value, the voltage across the capacitor 15, after a time lag imposed by the charging of the capacitor 18, causes a 4-layer diode 20 to break down and so render an NPN transistor 24 conductive. A relay 25 is now energized and closes contacts 26 to complete a holding circuit for itself and opens contacts 27 to cause isolation of the protected machine. The resistors 9, 10, 11 have a high temperature coefficient to provide added protection against excessive temperature rise of the machine.
GB1782260A 1960-05-20 1960-05-20 Protection circuit for use with multi-phase a.c. systems Expired GB973501A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
GB1782260A GB973501A (en) 1960-05-20 1960-05-20 Protection circuit for use with multi-phase a.c. systems

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB1782260A GB973501A (en) 1960-05-20 1960-05-20 Protection circuit for use with multi-phase a.c. systems

Publications (1)

Publication Number Publication Date
GB973501A true GB973501A (en) 1964-10-28

Family

ID=10101827

Family Applications (1)

Application Number Title Priority Date Filing Date
GB1782260A Expired GB973501A (en) 1960-05-20 1960-05-20 Protection circuit for use with multi-phase a.c. systems

Country Status (1)

Country Link
GB (1) GB973501A (en)

Similar Documents

Publication Publication Date Title
GB897891A (en) Improvements in or relating to overload voltage protection systems
US3218542A (en) Electronic circuit protector
ES346726A1 (en) Overload protection circuit
GB899305A (en) Short circuit protection device
GB981752A (en) Improvements in or relating to electrical protective relays
GB1031932A (en) A protective device for a super-conductor
GB973501A (en) Protection circuit for use with multi-phase a.c. systems
GB1102552A (en) Power supply circuit for electrical protective relays
GB1031467A (en) Overload protection clrcuit
GB1062854A (en) Improvements in circuits for protecting electrical power sources
GB950182A (en) Improvements in and relating to electrical circuits employing transistor networks
GB960667A (en) Voltage surge protector
GB1212318A (en) Overload protection circuit
GB1069626A (en) Improvements in electrical overload-protection systems
GB1309820A (en) Gatecontrolled phase failure protection circuit
GB1387386A (en) Protection circuits for transistor circuits
GB945200A (en) Improved voltage control device
GB1129178A (en) Improvements relating to overload protection in electric supply systems
GB1212419A (en) Improvements relating to electrical protective arrangements
GB907414A (en) Electric protective circuits
GB924717A (en) Circuit for protecting controllable semiconductor components against over-loading
GB1012762A (en) Improvements in or relating to transistorized voltage stabiliser circuits
GB886008A (en) Electro-magnetic relay circuits
GB942556A (en) Protection unit for use in multi-phase a.c. systems
GB978206A (en) A circuit and method for protecting a three phase star connected dynamo-electric machine