GB947418A - Improvements relating to electrical triggering circuits - Google Patents

Improvements relating to electrical triggering circuits

Info

Publication number
GB947418A
GB947418A GB2628561A GB2628561A GB947418A GB 947418 A GB947418 A GB 947418A GB 2628561 A GB2628561 A GB 2628561A GB 2628561 A GB2628561 A GB 2628561A GB 947418 A GB947418 A GB 947418A
Authority
GB
United Kingdom
Prior art keywords
transistor
circuit
zener
relay
collector
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
GB2628561A
Inventor
Eugeniusz Antoszewski
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.)
English Electric Co Ltd
Original Assignee
English Electric Co 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 English Electric Co Ltd filed Critical English Electric Co Ltd
Priority to GB2628561A priority Critical patent/GB947418A/en
Priority to FR903971A priority patent/FR1328811A/en
Publication of GB947418A publication Critical patent/GB947418A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/30—Modifications for providing a predetermined threshold before switching
    • 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
    • H02H3/083—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 for three-phase systems
    • 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
    • H02H3/20—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 voltage
    • H02H3/202—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 voltage for dc systems
    • H—ELECTRICITY
    • H03—ELECTRONIC CIRCUITRY
    • H03K—PULSE TECHNIQUE
    • H03K17/00—Electronic switching or gating, i.e. not by contact-making and –breaking
    • H03K17/51—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used
    • H03K17/56—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices
    • H03K17/60—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being bipolar transistors
    • H03K17/64—Electronic switching or gating, i.e. not by contact-making and –breaking characterised by the components used by the use, as active elements, of semiconductor devices the devices being bipolar transistors having inductive loads

Landscapes

  • Relay Circuits (AREA)

Abstract

947,418. Transistor switching; relay circuits. ENGLISH ELECTRIC CO. Ltd. July 16, 1962 [July 20, 1961], No. 26285/61. Heading H3T. [Also in Division H2] A transistor relay circuit comprises two transistors 10, 11, forming a balanced amplifier, connected so that when a D.C. signal is applied at 28, of such magnitude and polarity that transistor 10 becomes more conducting and transistor 11 less conducting, the decrease in the conductivity of transistor 11 causes the voltage drop across Zener diode 21 to increase above its breakdown voltage so that the current then flowing through the diode constitutes an output signal. The collector impedance of transistor 11 comprising resistors 13, 14, 15 and thermistor 16 is adjusted so that in the absence of a D.C. signal at 28 the collector voltage of transistor 11 is just below the Zener voltage of Zener diode 21 connecting the collector of transistor 11 with the base of transistor 22 in the collector circuit of which is an auxiliary relay 23. When the input signal is applied at 28 and transistor 11 is cut off, the Zener breakdown voltage is exceeded and transistor 22 is biased into conduction and relay 23 energized. In the protective relay circuit of Fig. 2 three balanced amplifiers, one for each phase of a three-phase system, are connected through blocking diodes 30 in parallel to the base of driving transistor 31 which is provided with a Zener diode 32 in its emitter circuit. Normally, the potentials of the collectors of transistors 11 are below the Zener breakdown voltage of diode 32, but when a D.C. signal is applied to the terminals 28 of any of the amplifiers and the appropriate transistor 11 becomes non-conducting transistor 31 is rendered conducting and S.C.R. 33 is energized, whereupon a circuit-breaker tripping coil 34 is energized to trip the circuit breaker. Capacitor 37 slows down the tripping action and prevents the circuit-breaker from tripping in response to transients.
GB2628561A 1961-07-20 1961-07-20 Improvements relating to electrical triggering circuits Expired GB947418A (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
GB2628561A GB947418A (en) 1961-07-20 1961-07-20 Improvements relating to electrical triggering circuits
FR903971A FR1328811A (en) 1961-07-20 1962-07-13 Transistorized electrical circuits applicable in particular to systems with electrical protection relays

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB2628561A GB947418A (en) 1961-07-20 1961-07-20 Improvements relating to electrical triggering circuits

Publications (1)

Publication Number Publication Date
GB947418A true GB947418A (en) 1964-01-22

Family

ID=10241237

Family Applications (1)

Application Number Title Priority Date Filing Date
GB2628561A Expired GB947418A (en) 1961-07-20 1961-07-20 Improvements relating to electrical triggering circuits

Country Status (1)

Country Link
GB (1) GB947418A (en)

Similar Documents

Publication Publication Date Title
GB1288660A (en)
US2875382A (en) Time delay devices for circuit interrupters
GB1459625A (en) Overcurrent protection circuit for transistor devices
GB1379550A (en) Electric protection device for motors
GB869351A (en) Selective trip arrangement utilizing circuit breakers which are coordinated with current limiting fuses
US3058036A (en) Semiconductor circuit interrupter
GB1097809A (en) Improved circuit breaker control system
GB947418A (en) Improvements relating to electrical triggering circuits
US3390307A (en) Electrical relays
GB1049676A (en) Overload protection circuit for high impedance amplifiers
GB1062854A (en) Improvements in circuits for protecting electrical power sources
US3262016A (en) Load protector
GB925027A (en) A protective circuit arrangement for transistors
GB1309820A (en) Gatecontrolled phase failure protection circuit
GB950182A (en) Improvements in and relating to electrical circuits employing transistor networks
SU978128A1 (en) Bipolar power supply unit
US3056043A (en) Gate having voltage divider shunting series emitter-collector paths and individual base-bias level setting means equalizing transistor leakage currents
GB1200025A (en) Improvements in power supply for circuit breaker tripping
GB1069626A (en) Improvements in electrical overload-protection systems
GB1100881A (en) Electrical protective relays
GB1212419A (en) Improvements relating to electrical protective arrangements
SU457139A1 (en) Current cutoff device
GB1129178A (en) Improvements relating to overload protection in electric supply systems
GB862099A (en) Improvements in or relating to electrical equipments incorporating transistors
GB1091519A (en) Automatic electric circuit breaker