EP0089607A1 - Mains-wired monitoring and security system - Google Patents
Mains-wired monitoring and security system Download PDFInfo
- Publication number
- EP0089607A1 EP0089607A1 EP83102557A EP83102557A EP0089607A1 EP 0089607 A1 EP0089607 A1 EP 0089607A1 EP 83102557 A EP83102557 A EP 83102557A EP 83102557 A EP83102557 A EP 83102557A EP 0089607 A1 EP0089607 A1 EP 0089607A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- unit
- signal
- peripheral
- count
- output
- 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.)
- Granted
Links
Images
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B29/00—Checking or monitoring of signalling or alarm systems; Prevention or correction of operating errors, e.g. preventing unauthorised operation
- G08B29/02—Monitoring continuously signalling or alarm systems
- G08B29/04—Monitoring of the detection circuits
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B25/00—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems
- G08B25/01—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium
- G08B25/06—Alarm systems in which the location of the alarm condition is signalled to a central station, e.g. fire or police telegraphic systems characterised by the transmission medium using power transmission lines
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B26/00—Alarm systems in which substations are interrogated in succession by a central station
- G08B26/001—Alarm systems in which substations are interrogated in succession by a central station with individual interrogation of substations connected in parallel
- G08B26/002—Alarm systems in which substations are interrogated in succession by a central station with individual interrogation of substations connected in parallel only replying the state of the sensor
Definitions
- This invention relates to a mains-wired system for monitoring predetermined zones spaced throughout a building, for instance residential premises, and for automatically initiating suitable action on the occurrence of an alarm condition.
- Known mains-wired monitoring and security systems i.e. systems employing the electric supply mains network for signal transmission, comprise a sensor, for example a temperature sensor, adapted to transmit to a remote location an alarm signal for energizing a suitable actuator.
- Systems of this type are not able, however, to monitor and to distinguish from one another a plurality of zones spaced throughout a building.
- the sensors may be connected to the associated actuators through special transmission systems, such as infrared radiation transmission systems, whereby the problems of the additional wiring is avoided.
- special transmission systems such as infrared radiation transmission systems
- a further object of the invention is to provide a monitoring and security system of the type indicated above, which is capable of giving timely warning of any malfunction of its main components and/or connections within the system itself.
- a mains-wired monitoring and security system comprising an electric supply mains network to which there are connected at least one central control unit, a plurality of peripheral detector units, and a plurality of peripheral actuating units.
- This system is principally characterized in that each unit comprises counter means adapted to cyclically count up to a count of M under the control of synchronizing means.
- Each peripheral detector unit is adapted to transmit via said mains network a code signal, when an associated sensor detects an alarm condition and the associated counter means arrive at a specific count N at the same time.
- At least one peripheral actuating unit is adapted to activate an associated actuator in response to the coded signal if the counter means associated therewith is simultaneously at the count N, this specific count N being common to at least one detector unit and at least one actuating unit.
- the central control unit is adapted to visually display the counted number N in response to said coded signal.
- the number N is preferably smaller than or equal to M/2, each of the peripheral detector units being further adapted to transmit the said coded signal via the mains network whenever the associated counter means reach a specific count of N + M/2.
- the central control unit comprises memory means for storing the specific numbers N + M/2 for each of the peripheral detector units, said memory means being controlled by said synchronizing means for cyclically reading these specific numbers and for actuating a display device if, on reading one of the specific numbers N + M/2, the central unit detects the absence of the corresponding coded signal.
- the system comprises a central control unit preferably provided with an independent power supply (not shown).
- the central unit includes a carrier wave transmitter 9 comprising an oscillator and a comparator (known and therefore not shown).
- Transmitter 9 is adapted to continuously generate a synchronizing signal having a frequency f1 (for instance 100 kc), which is applied to output terminal 38.
- transmitter 9 is adapted to apply the synchronizing signal also to a further output terminal 39 as long as a logic enable signal is present at its input terminal 40.
- Output terminal 39 of transmitter 9 is connected to an electric supply mains network 10 of a building through an interface 11 adapted to stay the mains voltage.
- the output of frequency divider 4 is applied to a counter stage 5 comprising for instance two four-bit counters in the form for instance of respective integrated circuits CD 4029 made by RCA.
- Counter stage 5 has a further output 8 to which it applies a logic enable signal (level "1") for the duration of one counting step (i.e. 10 msec in the example described) whenever the maximum count M is attained.
- Output 8 of counter stage 5 is connected to input 40 of transmitter 9, while counter outputs 6 are applied to respective inputs of a display device for instance of the luminous diode (LED) type.
- LED luminous diode
- the central unit further comprises a signal receiver 12, the input of which is connected to mains network 10 through interface 11, while its output in the form of a logic signal controls a corresponding input of a logic control stage 42.
- receiver 12 normally generates a logic level "0" at its output, said output changing to logic level "1" when receiver 12 detects a coded signal at its input which, as will be explained in detail later, has a fequency f2 (e.g. -80 Kc).
- Logic stage 42 has a further input connected to the output of a configuration memory 13 consisting for example of two integrated circuits CD 4031 made by RCA and constituting a shift register having a total of M memory locations.
- shift register 13 is initially programmed by storing the presence or absence of individual peripheral units of the system to be described later at corresponding memory locations. In the described example, the absence of peripheral units will be stored at the first sixty-four locations, while the presence of peripheral units will be stored in corresponding ones of the second group of sixty-four locations.
- the control input 41 of register 13 is connected to the output of frequency divider 4, so that the 128 locations of the register will be cyclically scanned with the frequency fO in synchronism with counter stage 5.
- Register 13 is adapted to generate a logic level "1" at its output only on the scanning of memory locations having stored therein the presence of at least one peripheral detecing unit.
- Logic control stage 42 may be composed of a plurality of commercially available logic elements and is provided with two outputs 46 and 47 alternatingly activated by successive counts of M/2.
- Output 46 is activated during the count from 0 to M/2 for generating the same logic level as present at the output of receiver 12.
- Output 47 is activated during the count from M/2 to M to generate a logic level "1" only if there is a difference between the logic levels at the outputs of receiver 12 and register 13.
- Output 47 of stage 42 is additionally adapted to activate an indicator device 45 when at level "1".
- An enable input 43 of display device 7 is selectively activated via a manually operable switch 44 or via one of the outputs 46 or 47 of stage 42. In every case that a logic level "1" is present at input 43, display device 7 is activated to display the count (between 0 and M/2) actually present at the outputs of counter stage 5.
- the monitoring and security system further includes a plurality of peripheral detector units, preferably provided with independent power supply (not shown), each one of which having the construction as shown in fig. 2 and being located at any point of the building to be monitored.
- each peripheral detector unit is identified by a specific number N ⁇ M/2 which may also be common to a group of such units.
- each peripheral detector unit comprises a detecting device 14 including a sensor (not shown) which may be of a per se known type and/or of different type for each such unit as required.
- the sensor may thus for example be a gas leak sensor, a break-in sensor, an inundation sensor, an incendiary sensor or the like.
- the output of detector 14 is normally at the logic level “0" and is adapted to change to level "1" whenever the sensor is activated by detecting an alarm condition.
- Each peripheral detector unit further comprises a counter stage 15 which may be composed of three four-bit counters of the type CD 4029 made by RCA.
- Counter stage 15 is in addition programmed to generate a logic command signal (logic level "1") at an output 17 (normally at logic level "0"), whenever the count of N + M/2 is reached.
- the said enable and command signals are generated at the respective outputs 16 and 17 of counter stage 15 for the duration of one counting step, i.e. for 10 msec in the example described.
- each peripheral unit may be identified by a different number N.
- the output of detector 14 and the output 16 of conter stage 15 are connected to respective inputs of a comparator stage 18, consisting for instance of an AND gate, arranged to generate an output command signal (logic level "1") in response to the simultaneous presence of logic level "1" at its inputs.
- the output of transmitter 19 is connected to mains network 10 through an interface unit 20 adapted to stay the mains voltage.
- Each peripheral detecting unit further includes a carrier wave receiver 21 the input of which is connected to mains network 10 through interface unit 20.
- Receiver 21 is substantially composed of a phase-locked loop circuit (PLL) which may be in the form of an integrated circuit of the type CD 4046 made by RCA.
- PLL phase-locked loop circuit
- receiver 21 is adapted to generate at its output 22 a reset signal which is applied to a reset input of counter stage 15 in response to receiving the already mentioned synchronization signal having the frequency f1 at its input.
- the phase-locked loop circuit of receiver 21 is controlled by the periodically received synchronization signal (received for each counting cycle T) for continuously generating a signal having the synchronization frequency f1 at a further output 23.
- the counting input 25 of counter stage 15 is thus controlled with the frequency f0 and thus in synchronism with the counter 5 of the central unit shown in fig. 1.
- the monitoring and security system further includes a plurality of peripheral actuating units, preferably provided with independent power supply (not shown), each of which is designed as shown in fig. 3 and located at any suitable point of a building to be monitored.
- each actuating unit is identified by a specific number N which may be common to a plurality of actuating units and/or to one or a plurality of peripheral detecting units.
- One or several detecting units may be associated with one or several actuating units as required.
- each peripheral actuating unit is provided with a carrier wave receiver 26, the input of which is connected to mains network 10 through an interface unit 27 adapted to stay the mains voltage.
- Receiver 26 is identical to receiver 21 of fig. 2 and may thus be comprised of an integrated circuit of the type CD 4046 made by RCA.
- receiver 26 is adapted to generate at its output 28 a reset signal which is applied to a corresponding input of a counter stage 29 in response to receiving the synchronization signal having the frequency f1 at its input.
- the phase-locked loop circuit of receiver 26 is controlled by the periodically received synchronization signal (received once for each counting cycle T, as already explained) to continuously generate a synchronization signal having the frequency f1 at a further output 30.
- the counting input 31 of counter stage 29 is also controlled with the frequency f0, i.e. in synchronism with the counter stage 5 of the central control unit.
- Counter stage 29 may be constituted by two four-bit counters of the type CD 4029 made by RCA, analogous to counter stage 5 of fig. 1.
- counter stage 29 is programmed to cyclically count up to the number M and to generate at an output 32 a logic enable signal (logic level "1") each time it reached the count N.
- the number N - M/2 may be different for each peripheral unit.
- the peripheral actuating units each include a further carrier wave receiver 33, the input of which is connected to mains network 10 through interface 27.
- Receiver 33 may likewise be formed, analogously to receiver 12 of fig. 1, by an integrated circuit of the type CD 4046 made by RCA, and is adapted to generate at its output 35 a command signal (for example logic level "1") which is applied to a corresponding input of a comparator and integrator stage 36 in response to receiving the coded signal having the frequency f2 at its input.
- a command signal for example logic level "1"
- Stage 36 is of a per se known type and adapted to store (for instance by means of a load capacitor (not shown)) the command signal received from receiver 33 whenever the enable signal is simultaneously present at the output of counter 290
- stage 36 is adapted to generate an activating output signal for an associated actuator 37 whenever it has stored the above mentioned command signal for a predetermined number of times (for instance three times) within a predetermined period of time.
- Actuator 37 may be of any type adapted to the specific purpose corresponding to the number N identifying the respective actuating unit and thus the type of the sensor provided in the at least one peripheral detecting unit indentified by the same number N.
- Actuator 37 may thus for instance comprise a solenoid valve adapted to interrupt the supply of a combustible gas or to activate an anti-incendiary sprinkler system, apparatus for closing fireproof doors; an alarm siren or the like.
- counter 5 of the central Unit (fig. 1) counts progressively with the frequency f0 determined by frequency divider 4.
- output 8 of counter 5 enables transmitter 9 to generate at irs output the synchronization signal having the frequency f1 for a duration of 10 mseco
- This signal is applied to mains network 10 through interface 11 and thus to all of the peripheral detecting and actuating units shown in figs. 2 and 3, resepctively.
- each peripheral detecting unit the synchronization signal is received, through interface unit 20, by the respective receiver 21, causing the latter to reset counter 15 by way of its output 22 and to generate at its output 23 a timing signal in synchronism with the frequency f1, as already explained.
- Receiver 21 thus controls counter 15 with the frequency f0 through frequency divider 24; after each reset operation (carried out each time the count of M is attained, as already explained, and effective to periodically eliminate any irregularity in the function of counter 15) counter 15 is in step with the timing signal generated by frequncy divider 4 of the central unit.
- counter stage 15 As counter stage 15 attains the count of N, it generates at its output 16 the logic level "1" which, only in case that sensor 14 be activated by an alarm condition, enables comparator 18 to activate transmitter 19. This means that if sensor 14 is active at the time that the count of N is attained, transmitter 19 applies the coded signal with the frequency f2 to mains network 10 for the duration of one counting step.
- transmitter 19 generates the same coded signal at its output, irrespective of the condition of sensor 14 and under the control of output 17 of counter 15, each time the said counter attains the count . of N + M/2, it being supposed that each peripheral detecting unit provided within the system is identified by a different number N ⁇ M/2.
- Each complete counting cycle from 0 to M (having a duration T of 1.28 sec in the example described) is divided into two periods of equal duration: a first counting period from 0 to M/2, and a second period for counting from M/2 to M, said periods being designates T1 and T2, respectively.
- coded signals having the frequency f2 are transmitted along mains network 10 only if at least one detecting unit is activated by an alarm condition; in this case the code signal is transmitted along the mains network at the instant at which the count of N identifying the activated detecting unit is attained.
- a plurality of code signals having the frequency f2 are transmitted along mains network 10 in timed succession.
- Each of these code signals is generated by a different detecting unit at the instance at which the count of N identifying the respective unit is attained.
- switch 44 normally connects input 43 of display device 7 with output 46 of logic stage 42.
- receiver 12 If during the period T1 the central control unit receives a coded signal having the frequency f2 (indicative of an alarm condition of a detecting unit N), receiver 12 generates a logic signal "1" which is applied to the input 43 of display device 7 through output 46 of stage 42 and switch 44. Display device 7 is thereby caused to display, for repetitive periods of 10 msec each, the counted number present at outputs 6 of counter 5, which corresponds to the number N indentifying the activated detecting unit. This periodic display continues until the cause for the alarm condition has been remedied, and allows the cause of the alarm to be immediately recognized.
- the central control unit receives coded signals having the frequency f2 each time register 13 generates at its output the logic level "1", while at output 47 of stage 42 there is normally present a logic level "0".
- receiver 12 does not receive a coded signal, the absence of this signal is indicative of a malfunction existing in the components and/or connections o F a corresponding peripheral detecting unit. Under these conditions, the output of receiver 12 is at logic level "0", while output 47 of stage 42 is at logic level "I”, thereby activating signalling or indicating device 45.
- the user is thus war B ed of the existing condition of malfunction and may now actuate switch 44 for connecting input 43 of display device 7 with output 47 of logic stage 42, causing display device 7 to display, for repetitive periods of 10 msec each, the count appearing at the outputs 6 of counter 5 and corresponding to the number N identifying the peripheral detecting unit beset by the malfunction. This enables the user to intervene in good time for remedying the cause of the malfunction.
- the synchronizing signal having the frequency f1 is received through interface unit 27 by receiver 26, causing the latter to reset counter 29 through its output 28 and to generate at its output 30 a signal in step with the frequency f1, as already said.
- Receiver 26 thus controls counter 29 through frequency divider 34 with the frequency f0; after each reset operation (carried out each time the count of M is attained and employed for periodically eliminating any irregularity in the function of counter 29), the counter 29 is in step with the timing signal generated by frequency divider 4 of the central unit.
- T1 receiver 33 If during the counting period T1 receiver 33 detects the presence of a coded signal having the frequency f2 in the mains network 10, it generates a command signal at its output, as already indicated.
- This command signal is able to activate comparator 36 only if counter 29 simultaneously generates an enable signal at its output 32.
- comparator 36 can obviously not be activated, as output 32 of counter 29 is at logic level "0" as already stated. In every case, the entire system functions also in the absence of voltage in the mains network 10, thanks to its independent power supply.
- peripheral actuating units may also be provided with means for carrying out an autodiagnosis analogous to those provided for the detecting units (transmitter 19 and associated connections in fig. 2).
- timing control of the monitoring and security system may be directly derived from mains network 10; in this case, frequency dividers 4, 24 and 34 are simply replaced by per se known mains voltage zero passage detectors.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Alarm Systems (AREA)
- Emergency Alarm Devices (AREA)
- Burglar Alarm Systems (AREA)
- Control Of Conveyors (AREA)
Abstract
Description
- This invention relates to a mains-wired system for monitoring predetermined zones spaced throughout a building, for instance residential premises, and for automatically initiating suitable action on the occurrence of an alarm condition.
- Known mains-wired monitoring and security systems, i.e. systems employing the electric supply mains network for signal transmission, comprise a sensor, for example a temperature sensor, adapted to transmit to a remote location an alarm signal for energizing a suitable actuator. Systems of this type are not able, however, to monitor and to distinguish from one another a plurality of zones spaced throughout a building. For this purpose one usually employs systems having a plurality of sensors of different types, such as incendiary sensors, innundation sensors, break-in sensors and the like, connected to associated actuators by means of additional wiring provided along with the electrical supply mains network, whereby the installation and operation of the entire system is undesirably complicated. Alternatively, the sensors may be connected to the associated actuators through special transmission systems, such as infrared radiation transmission systems, whereby the problems of the additional wiring is avoided. Such systems, however, require the employ of sophisticated and expensive transmitting and receiving equipment, whereby the overall construction of the system is again complicated and its operation rendered less reliable.
- In any case the correct operation of such known systems necessarily requires that all of their components as well as the connections between sensors and associated actuators are always in perfect working condition. On the other hand, any fault in the connections of the system does not become immediately apparent, so that in the case of an alarm condition the system can fail to react altogether or may even react in an incorrect manner.
- It is therefore an object of the invention to provide a mains-wired monitoring and security system of a relatively simple construction and reliable operation, which may be employed for monitoring a plurality of zones and for controlling a plurality of actuators spaced throughout a building.
- A further object of the invention is to provide a monitoring and security system of the type indicated above, which is capable of giving timely warning of any malfunction of its main components and/or connections within the system itself.
- In accordance with the invention, these objects are attained by a mains-wired monitoring and security system comprising an electric supply mains network to which there are connected at least one central control unit, a plurality of peripheral detector units, and a plurality of peripheral actuating units. This system is principally characterized in that each unit comprises counter means adapted to cyclically count up to a count of M under the control of synchronizing means. Each peripheral detector unit is adapted to transmit via said mains network a code signal, when an associated sensor detects an alarm condition and the associated counter means arrive at a specific count N at the same time. At least one peripheral actuating unit is adapted to activate an associated actuator in response to the coded signal if the counter means associated therewith is simultaneously at the count N, this specific count N being common to at least one detector unit and at least one actuating unit. The central control unit is adapted to visually display the counted number N in response to said coded signal.
- The number N is preferably smaller than or equal to M/2, each of the peripheral detector units being further adapted to transmit the said coded signal via the mains network whenever the associated counter means reach a specific count of N + M/2. The central control unit comprises memory means for storing the specific numbers N + M/2 for each of the peripheral detector units, said memory means being controlled by said synchronizing means for cyclically reading these specific numbers and for actuating a display device if, on reading one of the specific numbers N + M/2, the central unit detects the absence of the corresponding coded signal.
- The characteristics and advantages of the invention will become more clearly evident from the following description of an exemplary embodiment with reference to the accompanying drawings, wherein:
- figs. 1 to 3 show block diagrams of individual units connected to each other through an electric supply mains network in a preferred embodiment of a monitoring and security system according to the invention.
- With reference to fig. 1, the system comprises a central control unit preferably provided with an independent power supply (not shown). The central unit includes a
carrier wave transmitter 9 comprising an oscillator and a comparator (known and therefore not shown).Transmitter 9 is adapted to continuously generate a synchronizing signal having a frequency f1 (for instance 100 kc), which is applied tooutput terminal 38. In a per se known manner,transmitter 9 is adapted to apply the synchronizing signal also to a further output terminal 39 as long as a logic enable signal is present at itsinput terminal 40. - Output terminal 39 of
transmitter 9 is connected to an electricsupply mains network 10 of a building through aninterface 11 adapted to stay the mains voltage. -
Output 38 oftransmitter 9 controls a frequency divider 4 having adividing proportion of D = f1/f0 (for instance equal to 1000 in the example described), wherein f0 (equal to 100 c/sec) is the frequency of the output signal of frequency divider 4, said output signal being employed for the timing control of the system as will be described hereinafter. - The output of frequency divider 4 is applied to a
counter stage 5 comprising for instance two four-bit counters in the form for instance of respective integrated circuits CD 4029 made by RCA.Counter stage 5 is adapted to cyclically count up to a maximum number M (for instance M = 128) and is in a per se known manner designed so as to present two successive counting sequences from 0 to M/2 to itsmain output 6 during each counting cycle T = 1.28 seconds.Counter stage 5 has afurther output 8 to which it applies a logic enable signal (level "1") for the duration of one counting step (i.e. 10 msec in the example described) whenever the maximum count M is attained.Output 8 ofcounter stage 5 is connected toinput 40 oftransmitter 9, whilecounter outputs 6 are applied to respective inputs of a display device for instance of the luminous diode (LED) type. - The central unit further comprises a signal receiver 12, the input of which is connected to
mains network 10 throughinterface 11, while its output in the form of a logic signal controls a corresponding input of alogic control stage 42. In particular, receiver 12 normally generates a logic level "0" at its output, said output changing to logic level "1" when receiver 12 detects a coded signal at its input which, as will be explained in detail later, has a fequency f2 (e.g. -80 Kc). -
Logic stage 42 has a further input connected to the output of aconfiguration memory 13 consisting for example of two integrated circuits CD 4031 made by RCA and constituting a shift register having a total of M memory locations. In a per se known manner,shift register 13 is initially programmed by storing the presence or absence of individual peripheral units of the system to be described later at corresponding memory locations. In the described example, the absence of peripheral units will be stored at the first sixty-four locations, while the presence of peripheral units will be stored in corresponding ones of the second group of sixty-four locations. Thecontrol input 41 ofregister 13 is connected to the output of frequency divider 4, so that the 128 locations of the register will be cyclically scanned with the frequency fO in synchronism withcounter stage 5.Register 13 is adapted to generate a logic level "1" at its output only on the scanning of memory locations having stored therein the presence of at least one peripheral detecing unit. -
Logic control stage 42 may be composed of a plurality of commercially available logic elements and is provided with twooutputs Output 46 is activated during the count from 0 to M/2 for generating the same logic level as present at the output of receiver 12.Output 47 is activated during the count from M/2 to M to generate a logic level "1" only if there is a difference between the logic levels at the outputs of receiver 12 and register 13.Output 47 ofstage 42 is additionally adapted to activate anindicator device 45 when at level "1". - An enable
input 43 ofdisplay device 7 is selectively activated via a manuallyoperable switch 44 or via one of theoutputs stage 42. In every case that a logic level "1" is present atinput 43,display device 7 is activated to display the count (between 0 and M/2) actually present at the outputs ofcounter stage 5. - The monitoring and security system according to the invention further includes a plurality of peripheral detector units, preferably provided with independent power supply (not shown), each one of which having the construction as shown in fig. 2 and being located at any point of the building to be monitored. As will be explained in the following, each peripheral detector unit is identified by a specific number N≤ M/2 which may also be common to a group of such units.
- With reference to fig. 2, each peripheral detector unit comprises a detecting
device 14 including a sensor (not shown) which may be of a per se known type and/or of different type for each such unit as required. The sensor may thus for example be a gas leak sensor, a break-in sensor, an inundation sensor, an incendiary sensor or the like. The output ofdetector 14 is normally at the logic level "0" and is adapted to change to level "1" whenever the sensor is activated by detecting an alarm condition. Each peripheral detector unit further comprises acounter stage 15 which may be composed of three four-bit counters of the type CD 4029 made by RCA.Conter stage 15 is programmed in a per se known manner to cyclically count up to the number M = 128 and to generate a logic enable signal (logic level "1") at an output 16 (normally at logic level "0") whenever the count of N ≤ M/2 is reached.Counter stage 15 is in addition programmed to generate a logic command signal (logic level "1") at an output 17 (normally at logic level "0"), whenever the count of N + M/2 is reached. The said enable and command signals are generated at therespective outputs counter stage 15 for the duration of one counting step, i.e. for 10 msec in the example described. As already explained above, each peripheral unit may be identified by a different number N. - The output of
detector 14 and theoutput 16 ofconter stage 15 are connected to respective inputs of acomparator stage 18, consisting for instance of an AND gate, arranged to generate an output command signal (logic level "1") in response to the simultaneous presence of logic level "1" at its inputs.Output 17 ofcounter stage 15 and the output ofcomparator 18 are applied to the command input of a per se knowncarrier wave transmitter 19, comprising for instance an oscillator for generating a coded signal having, as already explained above, a frequency f2 = 80 Kc/sec in response to the presence of logic level "1" at its command input. The output oftransmitter 19 is connected tomains network 10 through aninterface unit 20 adapted to stay the mains voltage. - Each peripheral detecting unit further includes a
carrier wave receiver 21 the input of which is connected tomains network 10 throughinterface unit 20. -
Receiver 21 is substantially composed of a phase-locked loop circuit (PLL) which may be in the form of an integrated circuit of the type CD 4046 made by RCA. In a per se knownmanner receiver 21 is adapted to generate at its output 22 a reset signal which is applied to a reset input ofcounter stage 15 in response to receiving the already mentioned synchronization signal having the frequency f1 at its input. Also in a known manner, the phase-locked loop circuit ofreceiver 21 is controlled by the periodically received synchronization signal (received for each counting cycle T) for continuously generating a signal having the synchronization frequency f1 at afurther output 23. The latter is applied to acounting input 25 ofcounter stage 15 through afrequency divider 24 having a dividing coefficient D = f1/f0, i.e. 1000 in the example described. The countinginput 25 ofcounter stage 15 is thus controlled with the frequency f0 and thus in synchronism with thecounter 5 of the central unit shown in fig. 1. - The monitoring and security system according to the invention further includes a plurality of peripheral actuating units, preferably provided with independent power supply (not shown), each of which is designed as shown in fig. 3 and located at any suitable point of a building to be monitored. As will be explained in the following, each actuating unit is identified by a specific number N which may be common to a plurality of actuating units and/or to one or a plurality of peripheral detecting units. One or several detecting units may be associated with one or several actuating units as required.
- With reference to fig. 3, each peripheral actuating unit is provided with a carrier wave receiver 26, the input of which is connected to
mains network 10 through aninterface unit 27 adapted to stay the mains voltage. - Receiver 26 is identical to
receiver 21 of fig. 2 and may thus be comprised of an integrated circuit of the type CD 4046 made by RCA. - In particular, receiver 26 is adapted to generate at its output 28 a reset signal which is applied to a corresponding input of a
counter stage 29 in response to receiving the synchronization signal having the frequency f1 at its input. In addition, the phase-locked loop circuit of receiver 26 is controlled by the periodically received synchronization signal (received once for each counting cycle T, as already explained) to continuously generate a synchronization signal having the frequency f1 at afurther output 30.Output 30 of receiver 26 is applied to a countinginput 31 ofcounter stage 29 through afrwquency divider 34 having the same dividing coefficient D = fl/fO asfrequency divider 24 of fig. 2. Thus the countinginput 31 ofcounter stage 29 is also controlled with the frequency f0, i.e. in synchronism with thecounter stage 5 of the central control unit. -
Counter stage 29 may be constituted by two four-bit counters of the type CD 4029 made by RCA, analogous to counterstage 5 of fig. 1. - In a per se known manner,
counter stage 29 is programmed to cyclically count up to the number M and to generate at an output 32 a logic enable signal (logic level "1") each time it reached the count N. - As already said, the number N - M/2 may be different for each peripheral unit.
- The peripheral actuating units each include a further
carrier wave receiver 33, the input of which is connected tomains network 10 throughinterface 27.Receiver 33 may likewise be formed, analogously to receiver 12 of fig. 1, by an integrated circuit of the type CD 4046 made by RCA, and is adapted to generate at its output 35 a command signal (for example logic level "1") which is applied to a corresponding input of a comparator andintegrator stage 36 in response to receiving the coded signal having the frequency f2 at its input. -
Stage 36 is of a per se known type and adapted to store (for instance by means of a load capacitor (not shown)) the command signal received fromreceiver 33 whenever the enable signal is simultaneously present at the output of counter 290 - In addition,
stage 36 is adapted to generate an activating output signal for an associatedactuator 37 whenever it has stored the above mentioned command signal for a predetermined number of times (for instance three times) within a predetermined period of time. -
Actuator 37 may be of any type adapted to the specific purpose corresponding to the number N identifying the respective actuating unit and thus the type of the sensor provided in the at least one peripheral detecting unit indentified by the samenumber N. Actuator 37 may thus for instance comprise a solenoid valve adapted to interrupt the supply of a combustible gas or to activate an anti-incendiary sprinkler system, apparatus for closing fireproof doors; an alarm siren or the like. - In operation of the system,
counter 5 of the central Unit (fig. 1) counts progressively with the frequency f0 determined by frequency divider 4. On attaining the count of M,output 8 ofcounter 5 enablestransmitter 9 to generate at irs output the synchronization signal having the frequency f1 for a duration of 10 mseco This signal is applied tomains network 10 throughinterface 11 and thus to all of the peripheral detecting and actuating units shown in figs. 2 and 3, resepctively. - In each peripheral detecting unit the synchronization signal is received, through
interface unit 20, by therespective receiver 21, causing the latter to reset counter 15 by way of itsoutput 22 and to generate at its output 23 a timing signal in synchronism with the frequency f1, as already explained.Receiver 21 thus controls counter 15 with the frequency f0 throughfrequency divider 24; after each reset operation (carried out each time the count of M is attained, as already explained, and effective to periodically eliminate any irregularity in the function of counter 15)counter 15 is in step with the timing signal generated by frequncy divider 4 of the central unit. - As
counter stage 15 attains the count of N, it generates at itsoutput 16 the logic level "1" which, only in case thatsensor 14 be activated by an alarm condition, enablescomparator 18 to activatetransmitter 19. This means that ifsensor 14 is active at the time that the count of N is attained,transmitter 19 applies the coded signal with the frequency f2 tomains network 10 for the duration of one counting step. - In an analogous manner,
transmitter 19 generates the same coded signal at its output, irrespective of the condition ofsensor 14 and unter the control ofoutput 17 ofcounter 15, each time the said counter attains the count . of N + M/2, it being supposed that each peripheral detecting unit provided within the system is identified by a different number N≤ M/2. - Each complete counting cycle from 0 to M (having a duration T of 1.28 sec in the example described) is divided into two periods of equal duration: a first counting period from 0 to M/2, and a second period for counting from M/2 to M, said periods being designates T1 and T2, respectively.
- During the period T1, coded signals having the frequency f2 are transmitted along
mains network 10 only if at least one detecting unit is activated by an alarm condition; in this case the code signal is transmitted along the mains network at the instant at which the count of N identifying the activated detecting unit is attained. - During the period T2 (which, as will become more clearly evident in the following, is employed for carrying out an auto-diagnosis of the system), a plurality of code signals having the frequency f2 are transmitted along
mains network 10 in timed succession. Each of these code signals is generated by a different detecting unit at the instance at which the count of N identifying the respective unit is attained. - With reference to fig. 1, it is now supposed that switch 44 normally connects
input 43 ofdisplay device 7 withoutput 46 oflogic stage 42. - If during the period T1 the central control unit receives a coded signal having the frequency f2 (indicative of an alarm condition of a detecting unit N), receiver 12 generates a logic signal "1" which is applied to the
input 43 ofdisplay device 7 throughoutput 46 ofstage 42 andswitch 44.Display device 7 is thereby caused to display, for repetitive periods of 10 msec each, the counted number present atoutputs 6 ofcounter 5, which corresponds to the number N indentifying the activated detecting unit. This periodic display continues until the cause for the alarm condition has been remedied, and allows the cause of the alarm to be immediately recognized. - During the period T2, and as long as the entire system functions correctly, the central control unit receives coded signals having the frequency f2 each time register 13 generates at its output the logic level "1", while at
output 47 ofstage 42 there is normally present a logic level "0". - If, at the time that register 13 generates the logic . output level "1", receiver 12 does not receive a coded signal, the absence of this signal is indicative of a malfunction existing in the components and/or connections oF a corresponding peripheral detecting unit. Under these conditions, the output of receiver 12 is at logic level "0", while
output 47 ofstage 42 is at logic level "I", thereby activating signalling or indicatingdevice 45. The user is thus warBed of the existing condition of malfunction and may now actuateswitch 44 for connectinginput 43 ofdisplay device 7 withoutput 47 oflogic stage 42, causingdisplay device 7 to display, for repetitive periods of 10 msec each, the count appearing at theoutputs 6 ofcounter 5 and corresponding to the number N identifying the peripheral detecting unit beset by the malfunction. This enables the user to intervene in good time for remedying the cause of the malfunction. - As regards the peripheral actuating units (fig. 3), the synchronizing signal having the frequency f1 is received through
interface unit 27 by receiver 26, causing the latter to reset counter 29 through itsoutput 28 and to generate at its output 30 a signal in step with the frequency f1, as already said. Receiver 26 thus controls counter 29 throughfrequency divider 34 with the frequency f0; after each reset operation (carried out each time the count of M is attained and employed for periodically eliminating any irregularity in the function of counter 29), thecounter 29 is in step with the timing signal generated by frequency divider 4 of the central unit. - If during the counting
period T1 receiver 33 detects the presence of a coded signal having the frequency f2 in themains network 10, it generates a command signal at its output, as already indicated. - This command signal, however, is able to activate
comparator 36 only if counter 29 simultaneously generates an enable signal at itsoutput 32. This means that only the peripheral actuating unit, or units, respectively, identified by the same number N as the detecting unit generating the coded signal, is or are able to store the command signal in its or their comparator-integrator 36. Only if the command signal repeats itself over the above noted period of time for a predetermined number of complete counting cycles (three in the example described), doescomparator 36 activateactuator 37 as already described above. This permits unnecessary and unwanted activation ofactuator 37 caused for instance by faults in the mains network to be avoided and ensures such activation to take place only under genuine alarm conditions, thus contributing to the reliability of the entire system. - If
receiver 33 detects command signal during the auto- diagnosis period T2,comparator 36 can obviously not be activated, asoutput 32 ofcounter 29 is at logic level "0" as already stated. In every case, the entire system functions also in the absence of voltage in themains network 10, thanks to its independent power supply. - The above description clearly shows the structural simplicity and operational reliability of the monitoring and security system according to the invention, in which the central unit and the peripheral units operate in synchronism, and in which the peripheral units are cyclically scanned during alternating alarm signal periods and autodiagnosis periods.
- The described system may obviously varied in any suitable manner within the scope and spirit of the invention. It is thus obvious to the skilled artisan that with slight modifications of the circuitry the peripheral actuating units may also be provided with means for carrying out an autodiagnosis analogous to those provided for the detecting units (
transmitter 19 and associated connections in fig. 2). - In addition, the timing control of the monitoring and security system may be directly derived from
mains network 10; in this case,frequency dividers
Claims (4)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AT83102557T ATE23000T1 (en) | 1982-03-18 | 1983-03-15 | WIRED MONITORING AND SECURITY SYSTEM. |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
IT4571182 | 1982-03-18 | ||
IT45711/82A IT1159756B (en) | 1982-03-18 | 1982-03-18 | CONVEYED WAVE CONTROL AND SAFETY SYSTEM |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0089607A1 true EP0089607A1 (en) | 1983-09-28 |
EP0089607B1 EP0089607B1 (en) | 1986-10-15 |
Family
ID=11257509
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP83102557A Expired EP0089607B1 (en) | 1982-03-18 | 1983-03-15 | Mains-wired monitoring and security system |
Country Status (4)
Country | Link |
---|---|
EP (1) | EP0089607B1 (en) |
AT (1) | ATE23000T1 (en) |
DE (1) | DE3367037D1 (en) |
IT (1) | IT1159756B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0961254A3 (en) * | 1998-05-28 | 2000-06-28 | Wendling Umwelttechnik | Gas explosion protection device |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3482243A (en) * | 1966-10-28 | 1969-12-02 | Rca Corp | Protective system |
GB1414574A (en) * | 1973-01-31 | 1975-11-19 | Amp Inc | Remote signalling system and method |
US4156112A (en) * | 1977-12-07 | 1979-05-22 | Control Junctions, Inc. | Control system using time division multiplexing |
GB2023896A (en) * | 1978-06-23 | 1980-01-03 | Moeller As I C | Alarm systems |
EP0032135A2 (en) * | 1980-01-08 | 1981-07-15 | Raveningham Electronic Research Limited | Monitoring apparatus |
-
1982
- 1982-03-18 IT IT45711/82A patent/IT1159756B/en active
-
1983
- 1983-03-15 EP EP83102557A patent/EP0089607B1/en not_active Expired
- 1983-03-15 DE DE8383102557T patent/DE3367037D1/en not_active Expired
- 1983-03-15 AT AT83102557T patent/ATE23000T1/en not_active IP Right Cessation
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3482243A (en) * | 1966-10-28 | 1969-12-02 | Rca Corp | Protective system |
GB1414574A (en) * | 1973-01-31 | 1975-11-19 | Amp Inc | Remote signalling system and method |
US4156112A (en) * | 1977-12-07 | 1979-05-22 | Control Junctions, Inc. | Control system using time division multiplexing |
GB2023896A (en) * | 1978-06-23 | 1980-01-03 | Moeller As I C | Alarm systems |
EP0032135A2 (en) * | 1980-01-08 | 1981-07-15 | Raveningham Electronic Research Limited | Monitoring apparatus |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
EP0961254A3 (en) * | 1998-05-28 | 2000-06-28 | Wendling Umwelttechnik | Gas explosion protection device |
Also Published As
Publication number | Publication date |
---|---|
IT8245711A0 (en) | 1982-03-18 |
DE3367037D1 (en) | 1986-11-20 |
ATE23000T1 (en) | 1986-11-15 |
IT1159756B (en) | 1987-03-04 |
EP0089607B1 (en) | 1986-10-15 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US3927404A (en) | Time division multiple access communication system for status monitoring | |
US4612534A (en) | Method of transmitting measuring values in a monitoring system | |
US4446458A (en) | Monitoring and control system | |
US4672374A (en) | System for bilateral communication of a command station with remotely located sensors and actuators | |
US4361832A (en) | Automatic centralized monitoring system | |
US5019803A (en) | Detector units | |
US4532507A (en) | Security system with multiple levels of access | |
US4694282A (en) | Security monitoring system | |
US4462022A (en) | Security system with radio frequency coupled remote sensors | |
EP0259015A2 (en) | Fault-detecting intrusion detection device | |
US4926162A (en) | High security communication line monitor | |
AU607084B2 (en) | Data setting system for terminal units in remote supervisory and controlling system employing multiplex data transmission | |
US4339746A (en) | Alarm control center | |
US4551710A (en) | Method and apparatus for reporting dangerous conditions | |
US6198389B1 (en) | Integrated individual sensor control in a security system | |
US3792470A (en) | Coded tone multiplexed alarm transmission system | |
EP0676733A1 (en) | Detection system and method of operating same | |
US3921168A (en) | Remote sensing and control system | |
CA1181506A (en) | Security system with multiple levels of access | |
US4468664A (en) | Non-home run zoning system | |
US4665383A (en) | Security system with monitoring and warning circuits | |
US3813655A (en) | Monitoring systems and apparatus therefor | |
EP0089607A1 (en) | Mains-wired monitoring and security system | |
US3806921A (en) | Detector device | |
US3916405A (en) | System for supervision of rooms or buildings |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PUAI | Public reference made under article 153(3) epc to a published international application that has entered the european phase |
Free format text: ORIGINAL CODE: 0009012 |
|
AK | Designated contracting states |
Designated state(s): AT BE CH DE FR GB IT LI LU NL SE |
|
17P | Request for examination filed |
Effective date: 19831230 |
|
GRAA | (expected) grant |
Free format text: ORIGINAL CODE: 0009210 |
|
AK | Designated contracting states |
Kind code of ref document: B1 Designated state(s): AT BE CH DE FR GB IT LI LU NL SE |
|
REF | Corresponds to: |
Ref document number: 23000 Country of ref document: AT Date of ref document: 19861115 Kind code of ref document: T |
|
ITF | It: translation for a ep patent filed |
Owner name: INDUSTRIE ZANUSSI S.P.A. |
|
REF | Corresponds to: |
Ref document number: 3367037 Country of ref document: DE Date of ref document: 19861120 |
|
ET | Fr: translation filed | ||
PLBE | No opposition filed within time limit |
Free format text: ORIGINAL CODE: 0009261 |
|
STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT |
|
26N | No opposition filed | ||
ITTA | It: last paid annual fee | ||
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: CH Payment date: 19940211 Year of fee payment: 12 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: AT Payment date: 19940214 Year of fee payment: 12 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: BE Payment date: 19940224 Year of fee payment: 12 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: NL Payment date: 19940331 Year of fee payment: 12 Ref country code: LU Payment date: 19940331 Year of fee payment: 12 |
|
EPTA | Lu: last paid annual fee | ||
EAL | Se: european patent in force in sweden |
Ref document number: 83102557.2 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LU Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19950315 Ref country code: AT Effective date: 19950315 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: LI Effective date: 19950331 Ref country code: CH Effective date: 19950331 Ref country code: BE Effective date: 19950331 |
|
BERE | Be: lapsed |
Owner name: ZELTRON ISTITUTO ZANUSSI PER L'ELETTRONICA S.P.A. Effective date: 19950331 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: NL Effective date: 19951001 |
|
REG | Reference to a national code |
Ref country code: CH Ref legal event code: PL |
|
NLV4 | Nl: lapsed or anulled due to non-payment of the annual fee |
Effective date: 19951001 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: FR Payment date: 19970210 Year of fee payment: 15 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: SE Payment date: 19970217 Year of fee payment: 15 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: GB Payment date: 19970220 Year of fee payment: 15 |
|
PGFP | Annual fee paid to national office [announced via postgrant information from national office to epo] |
Ref country code: DE Payment date: 19970224 Year of fee payment: 15 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: GB Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980315 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: SE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19980316 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: FR Free format text: THE PATENT HAS BEEN ANNULLED BY A DECISION OF A NATIONAL AUTHORITY Effective date: 19980331 |
|
GBPC | Gb: european patent ceased through non-payment of renewal fee |
Effective date: 19980315 |
|
PG25 | Lapsed in a contracting state [announced via postgrant information from national office to epo] |
Ref country code: DE Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES Effective date: 19981201 |
|
EUG | Se: european patent has lapsed |
Ref document number: 83102557.2 |
|
REG | Reference to a national code |
Ref country code: FR Ref legal event code: ST |