NO892557L - Pulse-encoded smoke / fire detection system. - Google Patents

Pulse-encoded smoke / fire detection system.

Info

Publication number
NO892557L
NO892557L NO89892557A NO892557A NO892557L NO 892557 L NO892557 L NO 892557L NO 89892557 A NO89892557 A NO 89892557A NO 892557 A NO892557 A NO 892557A NO 892557 L NO892557 L NO 892557L
Authority
NO
Norway
Prior art keywords
voltage
transponders
line
logic level
data
Prior art date
Application number
NO89892557A
Other languages
Norwegian (no)
Other versions
NO892557D0 (en
Inventor
Lee D Tice
Todd W Fritz
Mark A Kilcommons
Original Assignee
Pittway Corp
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
Priority claimed from US07/111,811 external-priority patent/US4916432A/en
Application filed by Pittway Corp filed Critical Pittway Corp
Publication of NO892557D0 publication Critical patent/NO892557D0/en
Publication of NO892557L publication Critical patent/NO892557L/en

Links

Landscapes

  • Fire Alarms (AREA)
  • Fire-Detection Mechanisms (AREA)

Abstract

Røk/branndeteksjonssystem (10) hvor en sentral styreenhet (12) overfører data til «køterna transpondere (24, 26) over en overføringslinje (22) som samtidig tjener som kraftforsynings- linje, ved pulskodemodulasjon (PCM) av tilfør- selsspenningen, og hvor transponderne (24, 26) står i signalforbindelse med styreenheten (12) ved hjelp av pulsbreddemodulerte (FHM) strøm- pulser. En prosessor (30) i styreenheten (12) tilveiebringer en normal driftsspeaning pl linjen (22) og sender ut et dataord BOB omfat- ter flere databit til transponderne (24, 26) ved å endre linjespenningen fra den nominelle verdi til en første spenning som tilsvarer et første logisk nivå eller til en andre spenning atm tilsvarer et andre logisk nivå. En dekoder (84) i hver transponder (24) detekterer spennings- endringen og fastlegger det logiske nivå for hver overført bit ved å måle det overførte spenningsnivå umiddelbart etter detekteringen av spenningsendringen. Transponderen (24) sen- der så tilbake datasignaler til styreenheten (12), idet hvert signal har en varighet som bygger på de data som skal sendes tilbake.Smoke / fire detection system (10) wherein a central control unit (12) transmits data to the "transponders" (24, 26) over a transmission line (22) which simultaneously serves as a power supply line, by pulse code modulation (PCM) of the supply voltage, and where the transponders (24, 26) are in signal communication with the control unit (12) by pulse width modulated (FHM) current pulses. A processor (30) in the controller (12) provides a normal operating voltage on the line (22) and outputs a data word BOB comprising multiple data bits to the transponders (24, 26) by changing the line voltage from the nominal value to a first voltage which corresponds to a first logic level or to a second voltage atm corresponds to a second logic level. A decoder (84) in each transponder (24) detects the voltage change and determines the logic level for each transmitted bit by measuring the transmitted voltage level immediately after the detection of the voltage change. The transponder (24) then sends back data signals to the controller (12), each signal having a duration based on the data to be returned.

NO89892557A 1987-10-21 1989-06-20 Pulse-encoded smoke / fire detection system. NO892557L (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
US07/111,811 US4916432A (en) 1987-10-21 1987-10-21 Smoke and fire detection system communication
PCT/US1988/003217 WO1989004032A1 (en) 1987-10-21 1988-09-16 Smoke and fire detection system communication

Publications (2)

Publication Number Publication Date
NO892557D0 NO892557D0 (en) 1989-06-20
NO892557L true NO892557L (en) 1989-06-20

Family

ID=26777820

Family Applications (1)

Application Number Title Priority Date Filing Date
NO89892557A NO892557L (en) 1987-10-21 1989-06-20 Pulse-encoded smoke / fire detection system.

Country Status (1)

Country Link
NO (1) NO892557L (en)

Also Published As

Publication number Publication date
NO892557D0 (en) 1989-06-20

Similar Documents

Publication Publication Date Title
ES2011164A6 (en) Smoke and fire detection system communication.
BR9810507A (en) Power control equipment, and, process to selectively control power levels.
KR960016299A (en) Control system, signal modulation and demodulation method
JPS6471326A (en) Method of demodulating bi-phase signal
KR970019727A (en) Control / Management Signaling / Receiving System
HK1023247A1 (en) Data communication device and data communication method
ATE213555T1 (en) TRANSPONDER SYSTEM WITH ACKNOWLEDGMENTS ASSOCIATED WITH THE CORRESPONDING TRANSPONDER
EP0172236A1 (en) Method and apparatus for detecting the collision of data packets.
NO892557L (en) Pulse-encoded smoke / fire detection system.
GB1043447A (en) Pulse code signalling system
EP0370943A3 (en) System for telemetering data
KR870000297B1 (en) Infra-red data communications system for coupling a battery powered data entry device to a microcomputer
NO902173L (en) DEVICE AND PROCEDURE FOR IDENTIFICATION OF MESSAGE INITIATION IN A PROCESS MANAGEMENT NETWORK.
SE9503876D0 (en) Way to ensure data integrity during a repeater transfer
JPS573153A (en) Fault detection system
EP0575175B1 (en) Detection system
US3482035A (en) Data message handling system
EP0196634A3 (en) Network system
EP0138584A3 (en) Self referring type of optical communication system
JPS6468052A (en) Modem telephone set
WO1998053337A3 (en) System and method for simultaneous data link with multipurpose radar operations
EP0339922A3 (en) Combined rate/width modulation arrangement
JPS577658A (en) Pulse-coding system for burst signal
JPS55120256A (en) Multilevel code transmission system
NO991322L (en) Signaling method and transmitter used in a digital radio system