JPS5498198A - Alarm circuit system - Google Patents

Alarm circuit system

Info

Publication number
JPS5498198A
JPS5498198A JP435478A JP435478A JPS5498198A JP S5498198 A JPS5498198 A JP S5498198A JP 435478 A JP435478 A JP 435478A JP 435478 A JP435478 A JP 435478A JP S5498198 A JPS5498198 A JP S5498198A
Authority
JP
Japan
Prior art keywords
trq
circuit
detected
alarm
oscillation
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.)
Pending
Application number
JP435478A
Other languages
Japanese (ja)
Inventor
Masao Meguro
Masatoshi Nakasu
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.)
Hitachi Ltd
Renesas Eastern Japan Semiconductor Inc
Hitachi Iruma Electronic Co Ltd
Original Assignee
Hitachi Ltd
Hitachi Tohbu Semiconductor Ltd
Hitachi Iruma Electronic 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 Hitachi Ltd, Hitachi Tohbu Semiconductor Ltd, Hitachi Iruma Electronic Co Ltd filed Critical Hitachi Ltd
Priority to JP435478A priority Critical patent/JPS5498198A/en
Publication of JPS5498198A publication Critical patent/JPS5498198A/en
Pending legal-status Critical Current

Links

Landscapes

  • Emergency Alarm Devices (AREA)

Abstract

PURPOSE: To improve the sensitivity of alarm system by constituting a circuit in which an alarm is generated by ocillating an oscillation circuit only when the detection circuit functions.
CONSTITUTION: When there is no resisting body to be detected such as for example water leakage between the pair of sensors, Darlington connected detecting transistors TRQ2 and Q3 are "OFF" and, therefore, the base current does not flow through oscillation transistor TRQ1, which is functioning as a load in portion of the primary side of transformer and, consequently, there is no oscillation. However, when there is a resisting body between sensors, TRQ2 and Q3 are turned "ON", base current flows through TRQ1, the main circcuit oscillates as a blocking circuit and alarm is is given form speaker SP. Since this circuit amplifies even when the current is very weak, a resisting body of even very high resistance can be detected. When the resistance of body to be detected is comparatively low, one transisitor can be used instead of Darlington connection.
COPYRIGHT: (C)1979,JPO&Japio
JP435478A 1978-01-20 1978-01-20 Alarm circuit system Pending JPS5498198A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP435478A JPS5498198A (en) 1978-01-20 1978-01-20 Alarm circuit system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP435478A JPS5498198A (en) 1978-01-20 1978-01-20 Alarm circuit system

Publications (1)

Publication Number Publication Date
JPS5498198A true JPS5498198A (en) 1979-08-02

Family

ID=11582058

Family Applications (1)

Application Number Title Priority Date Filing Date
JP435478A Pending JPS5498198A (en) 1978-01-20 1978-01-20 Alarm circuit system

Country Status (1)

Country Link
JP (1) JPS5498198A (en)

Similar Documents

Publication Publication Date Title
DE59307119D1 (en) Solid state relay
JPS56117409A (en) Amplifying device
JPS5498198A (en) Alarm circuit system
JPS5717226A (en) Integrated circuit
JPS5425145A (en) Detection circuit for unbalanced dc voltage of output amplifier on two-power- supply system
JPS5556495A (en) A.c. motor controller
JPS5775568A (en) Ringing converter
JPS5555605A (en) Protective circuit for power output circuit
JPS52102657A (en) Transistor amplifier circuit
JPS6429997A (en) Environmental abnormality alarming facility
JPS5484909A (en) Signal detection system
JPS5437448A (en) Overload detecting circuit of power amplifier
JPS5284423A (en) Invertor protection device
JPS54103381A (en) Battery voltage detecting circuit
JPS57179989A (en) Sense circuit
JPS54104869A (en) Position detecting device
JPS5383013A (en) Overcurrent protection for converter
JPS5437475A (en) Transient state detecting device
JPS52119106A (en) Supervisory circuit for line signal
JPS54139043A (en) Protective circuit for power output circuit
JPS52125264A (en) Semiconductor circuit
JPS5347949A (en) Arc extinguishing detection circuit
JPS5242352A (en) Arc detection control circuit
JPS55163461A (en) Absolute value detection circuit
JPS53133321A (en) Gamma circuit