FR2483104A1 - ALARM ZONE INDICATOR DEVICE - Google Patents

Abstract

THE INVENTION RELATES TO AN ALARM ZONE INDICATOR DEVICE IN A MULTI-SENSOR ALARM INSTALLATION. THE CONTROL UNIT AND EACH SENSOR CONTAIN A COUNTER, AND A CLOCK CIRCUIT IN THE CONTROL UNIT MAKES ALL COUNTERS PROGRESS IN SYNCHRONISM. WHEN A SENSOR DETECTS AN ALARM CONDITION, IT WILL SEND A RETURN SIGNAL TO THE CONTROL UNIT WHEN ITS OWN COUNTER PASSES TO A POSITION THAT IS AFFECTED TO IT. THE INVENTION APPLIES IN PARTICULAR TO THE MODIFICATION OF EXISTING BREAK-IN ALARM INSTALLATIONS.

Description

The present invention relates to monitoring devices and

of devices using sensors

  multiple, and relates more particularly to a

  signaling or zone indicating device which indicates the position of a monitored area while using only the cable normally provided for the device

with multiple sensors.

  Although the invention relates in a general manner to

  equipment to monitor and control devices in which data collected at remote locations are transmitted to a central control unit by a cable, it will first be described in

  look at a burglar alarm device at several

  son in which the data to be transmitted to the control unit are of a relatively simple nature. With respect to the burglar alarm signals, the signal transmitted to the control unit may simply be the presence of a pulse to indicate that an alarm condition has occurred. In general, no further information is needed because the sensors at remote locations are all of a similar type; that is, they only detect a tyrpe

alarm condition.

  As will be explained later, the invention also applies to the transmission of more complex data which may include discrimination between different types of alarm, for example fire or burglary and, in other modes embodiment, the monitoring of ambient temperatures, boiler pressure, elevator operation, emergency lighting, etc. But in its least complex aspect, the present zone indication device will first be described in

  look at the signage of a break-in.

  In multi-wire intrusion detection devices, in which a number of

  The sensors are connected in parallel to a cable with

  If there is a break-in or a violation, it is sometimes difficult to determine the position of the break-in or the violation. Thus, if a guard or other responsible person "must react to an alarm indication, it is difficult for him to know where the security breach occurred and he is

  so difficult to know how to react.

  Until now, the signaling devices imposed a separate cable or group of cables to indicate the location of the alarm condition. But the establishment of multiple son in addition to those already used for the burglar detection device is at the

  sometimes costly and sometimes impossible, following ns-

  tallation. Audible alarms at the point of break-in or breach give an audible indication on this point,

  but they are often ineffective in that they give

  give the person who commits the breach a warning

  enough for him to escape. In addition, these

  positive warn this individual that his presence has been detected and he can take steps to avoid being captured, which may endanger security personnel who search for the break-in. In addition, audible alarms at the sensor position are ineffective in alerting security personnel to the location of the crash if the central control unit is not within hearing range of all transceivers or

individual sensors.

  In order to provide an indication of area with a multi-wire cable already in place, a device

  digital coding can be used, in which each

  each of the transceivers connected to the cable is

  assigned a different address code which may be

  The central unit is coerced on a time sharing basis, the central unit transmitting a series of codes which, when detected by a particular receiver unit, cause the unit output to be coupled.

  transceiver with the multi-wire cable.

  Of course, it imposes considerable circuits of reconaissance and code production. In addition, the update of these installers of these devices

  complicated by knowledge of the code and procedures

  hard code-making. In addition, a device is required to separate: zone code signals from control signals normally used to control the individual sensors connected to the cable

  to several sons. The control signals are generally

  of digital nature and therefore differ little from the digital signals that must be

a given sensor.

  There is reason to believe that a better type of

  zone indication using existing cables would be a device in which the interrogation is

  made acoustically or at least at acoustic frequencies

  ticks, a predetermined audible frequency being

  each sensor. It would be conceivable to use elements of agreement determination of a range

  frequency in the sensors, so that these

  can be interrogated by an acoustic signal

at the appropriate frequency.

  It should be noted, however, that the production of a large number of different acoustic frequencies is both expensive and electronically complicated, as is the filtering system required to filter the sensor responses relative to the subcarrier. acoustics that would be used. In addition, since ultra-sound equipment is sometimes used

  to the sensor for the detection of burglary, a trans-

  modulation could occur between ultrasonic organs and acoustic organs in the signaling device. In the digitally coded devices or acoustic code devices described above, the false alarm rate is unduly high due to the aforesaid transmodulation between the sensor and control signals, and the zone indication signals. transmitted on the same wires. If separate wires were used for the zone indication, the price of the whole would increase considerably if this set were in

  achievable for a given position.

  In one aspect, the invention thus relates to a zone indicating device in which no separate wire is used to provide this indication. In

  a device of this kind, meters controlled simul-

  time by clock are used in a central unit

  control and in the sensors. A coincidence

  counting between the control unit and a sensor

  it has been activated during the cycle

  count. Thus, the only additional circuit required

  For each sensor is a counter in which a specified counting output is connected, for example by a removable connection pin, to the rest of the sensor circuits to compensate for it. This makes it exceptionally easy to modify a device

  installed so that it gives the zone indication. The UTI

  a local counter and a connection pin.

  xion to operate and establish the identity of a particular sensor leads to an extremely simple coding organ imposing only minimal skill on the part of

of the installer.

  With regard to the detection of alarm condition, in one embodiment, a panel of

  signaling is provided, with indicator lamps

  trice or the like associated with each other with a given counter output. The counter of the control unit is controlled by clock or it progresses in synchronism with the counters of the sensors, an output of a

  given sensor being authorized only if a signal of

  tie appears at a specified output of its counter.

  Each sensor authorization device is connected to a different output terminal of the meter. during

  a co-counting cycle9 the sensors are allowed

  in order to couple an indicator signal

  The signals on this are applied in parallel to a number of 3 ports AND to several inputs in the control unit. These AND gates are each associated with a counter output terminal in the control unit. outputs of the AND gates attack the respective indicators of the

  sign of recognition If a particular sensor

  that an output indicating a condition of alarms it r-

  result of the simultaneous arrival of a signal of this sensor with a corresponding output signal of the counter of

  the control unit that the corresponding AND gate deli-

  a signal to light a lamp or to give any

  other indication on the sign

  alarm condition dication is locked or pre-

  so that even if the coincidence of a counter output signal and a sensor signal lasts only during a clock pulse, the flag is maintained to specify the particular sensor whose

  output signal indicated an alarm condition.

  It is therefore sufficient to associate with each sensor a pulse detection circuit, a counter and an AND gate, an input of this gate being connected to an output of a burglar detector, a second input of the door being connected. at an exit terminal

  corresponding counter, and the third

  gate being connected to the output of the detector.

  pulse generator so that at the coincidence of the three signals, an output signal is applied to the cable to the control unit. It thus appears that an alarm signal for a given sensor is available for only one clock pulse and this is the coincidence

  arrival of this corresponding output signal from the

  te AND with a counter output from the control unit that specifies which of the sensors that issued

the alarm indication signal.

  In one embodiment, the alarm indication signal is transmitted to the control unit on the same

  wire that is normally used to feed the

  detector. For ultrasonic sensors, this wire transmits a high frequency signal. It is necessary

  note that an impulse is easily distinguishable from a

  high frequency signal by means of filtering. Thus, at the control unit, there is little difficulty in determining the area or position of the alarm condition by eliminating the high frequency signal, leaving the impulse coming from the door AND the sensor that emits an alarm signal. In this latter embodiment, there are only a few transmodulations. This device is extremely inexpensive because it uses only very simple meters with doors

  3 AND several entries. It does not impose any complicated modules

  digital code decryption or any device

  acoustic for zone indication.

  Moreover, and as will be explained later,

  modification of an already installed device for the in-

  A zone without a separate wire is facilitated if the Fone indication signals are compatible with the already existing signals used in the device.

  In place, for example, in one embodiment of

  The clock for the burglar alarm cable can be the same as that used to transmit impulse to the sensor. Thus, no other clock or pulse generator circuit is needed and the signals are detected at each sensor in normal operation A redundancy for alarm indications can

  be achieved by ensuring that a condition of

  the tear is indicated not only by the presence of a signal on the alarm wire, but also by a signal from a particular ET1 on another wire,

  for example the high frequency wire.

  It has been assumed above that the condition signal

  alarm was only placed on the wire during

  presence of an alarm condition. But how that will be.

  explained afterwards, the alarm condition signal

  may be the absence of a normally

  which is deleted according to a condition d8a =

  detected or as a result of a cut or an interruption

  rupturing of the wires of the cable. This offers some

  tection center violIations, because the cut of the line | and the suppression of the signal constitute in themselves a

  alarm condition which can be monitored by the pre-

feel device.

  The device according to the invention has been described below.

  in its application to an alarm detection circuit but it is obvious that this detection is not

  that one of many conditions that may be over-

  remotely monitored and reported.

  For example, in surveillance devices

  and device control, there are three different types of

  data, namely alarm data, recorded data and control data,

  alarm data may relate to a dangerous situation.

  reuse; for example an overpressure in a boiler.

  The recorded data may include the recording of a power consumption. The order data includes data that is analyzed from

  way that a control function can be exercised.

  So the ambient temperature can be monitored

for controlling an oven.

  It is important to be able to collect data remotely without the need for complicated modulator-demodulators or digital coding devices and to be able to conveniently select and program the sensors so that they can perform different functions of data collection.

  remote and control data.

  In addition, in the realization of the devices of monitoring and automation or control,

  Security features can also be provided.

  For example, the device may be programmed to allow, when fire detectors and

  anti-theft alarm detectors are used, determining the

  the particular features that have worked. This is important as to whether fire services should be called or not.

police services.

  In addition, there are some sensors that can be operated on a twenty-four hour by twenty-four per day basis while other sensors can be operated only the following or at times when no activity is expected. For example, the detection of infractions by shop windows is often monitored twenty four hours a day while ultrasonic motion detectors are constantly

2483104 '

  inhibited during the hours of work. It is therefore important to be able to select the base on which

the sensors are monitored.

  Another function that can be planned is the

  troduction of an entry or exit delay for a

  instant alarm. This characteristic is general-

  intended to allow a person to arm the device and then exit with the device in

  operation for a given period of time after the

  Similarly, the alarm that would normally be triggered at

  entry into a protected area may be inhibited

  during a given period in order to allow an outorised person to render the alarm device

  In addition, there are oas o for reasons

  In the case of redundant sounds an alarm is detected if another sensor provides the same indication of alarm condition. It is therefore important to be able to program the sensor to instantly deliver an alarm condition signal or to deliver it only if

  second redundancy signal is present.

  There may be cases where it is desirable for the remote sensor to produce a local alarm at the location where it is installed. This is contrary to the case of silent alarm in which all alarm conditions

  are transmitted to the control unit.

  It may be desirable to provide a pre-alarm "sonalert" l re-memory when it is necessary to remind the authorized person that the device is

Operating.

  Of course, there may be different alarms

  indicating an attack or burglary.

  According to the invention, it is possible during the com-

  the sensors counters, which function

  as address counters, to inhibit the generation of clock pulses and to produce a second group of clock pulses to control another counter or auxiliary counter in each sensor. The outputs of this auxiliary counter are respectively connected, for example by short-circuit pins, to circuits which fulfill the functions described. Thus, when a predetermined sensor has been addressed by address clock pulses, these clock pulses can be inhibited and the auxiliary counter of the sensor can be controlled, with information transfer occurring when a circuit

  of particular function is ordered during the progress

-session of the auxiliary meter.

  Each sensor can fill a group of safety or alarm function functions, then data collection and control functions. Alternatively, the sensor may be adapted particularly, or for

  security functions, or-for

  data collection. With regard to the monitoring of the data, if three conditions are monitored, the corresponding sensors can be interrogated by the control of the auxiliary counter. If only one of the three conditions is to be monitored in a given sensor, only the corresponding connection pin is inserted. With regard to the monitoring of safety conditions, a monitoring pin can be

  in place to give the command unit an indica-

  For example, the sensor operates twenty-four hours a day. By way of example, in one embodiment, the alarm condition sensor is coupled: 30 with the control unit on the first pulse

  auxiliary clock. Then, after a predetermined number

  of the auxiliary counter clock pulses, the

  setting up a connection pin gives the indica-

  that the alarm is a twenty-four hour alarm

per day.

  With regard to the data collection functions, the information transmitted to the control unit may consist of an analog signal

  in one embodiment 2 they consist of a cou-

  The use of a current-based device, unlike a voltage-based device, eliminates the need to introduce compensation for the length of the interconnect cable, which is generally subject to error. sometimes desirable to inhibit the address clock pulses often

  Simplified data may be transmitted in the

  between these clock pulses

  Thus, no inhibition is necessary for

  D5 born that are not complex. In general, data

  can be treated in this way9

  say that complex data can impose

address clock.

  Clock pulses for addressing and

  auxiliary functions can be distinguished by using

  reading positive pulses for 1 address clock and negative pulses for the clock of the auxiliary functions

  Other features and advantages of the invention

  will be better understood by reading the description

  FIG. 1 is a simplified diagram of a burglar alarm device using a multi-wire cable and in which a plurality of sensors are connected in accordance with the following diagrammatic drawings. parallel, Figure 2 is a simplified diagram of a mode of

  implementation of a zone indicator device, illus-

  trant a zone designation block in a sensor,

2483104-

  a zone detection block in a control unit

and a sign, -

  FIG. 3 is a schematic diagram of an anti-short circuit and anti-tamper circuit for an alarm condition indicating device with separate wireless zone indication. FIG. Figure 5 is a schematic diagram of a device modified to be associated with a four-wire tamper-evident device in place, FIG. simplified schematic of an extended capacity monitoring and control device used for data collection and control

  distance, also using a four-wire cable.

  FIG. 1 therefore represents a multi-wire burglar alarm device which comprises a control unit 10 and a number of sensors, designated in FIG. 12 and 14, connected in parallel to the wires of the interconnection circuit. represent. In this device, SW violation switches are located in the sensors and are opened as a result of a

violation of the case of a sensor.

  In a type of multi-wire cable circuit, the functions of the four wires are as follows: the bottom wire, or black wire designated by N, is used as ground wire or return wire of the circuit; the red wire designated R is used to supply DC power to the sensors; designated yellow thread

  J is generally used to transmit

  high-frequency signals, for example to supply ultrasonic equipment in a sensor, and it can also

  Used for an anti-alarm indication signal

  violation and short-circuit, which consists of a continuous signal superimposed on the alternating signal delivered on the yellow wire; and the green wire designated V is used both for providing control signals to the sensors for locking, quitting and blocking, as well as for returning an alarm signal to the control unit In the case of an alarm signal developed on the green wire, it is generally the grounding of this wire, detected at the control unit so that the tear unit 15 is triggered. This alarm unit can be triggered by grounding the green wire with a

  indication of violation detected on the young wire.

  As noted above, the occurrence of a gas mark actually indicates that a break-in has occurred, but the location where an individual has been damaged is questionable for the purpose of producing a low-cost indicator device. without having to use compliant addressing systems, the illustrated embodiment

  FIG. 2 comprises a command unit '10 comprising

  a zone detection circuit 20 and an indicator panel 22 connected to the sone detection circuit.

  a sensor designated by 12 has a circuit 24 for de-

  zone signatory which, when used together

  with the zone detector and the indicating panel, indicates that of the sensor detectors 26 which has detected a break-in, the particular sensor which includes this

  detector being identified on the road sign.

  The way in which this result is obtained in the pre-

  This embodiment will now be described: as already indicated, the sensors and the control unit comprise counters, in this case the counters 30 and 32. These counters can generally be current shift registers available. in commerce, or in fact any type of

  counter or equivalent, which progresses with

  clock sounds may be suitable. In order to make

  simultaneously advance the counters 30 and 32, a

  The pulse generator 34 delivers pulses to a conductor 16 via a switch 38 controlled by a control unit 40 to a line 42 connected in parallel to all the sensors. A unit

  44 pulse detection is provided in each

  to detect the occurrence of these regular pulses.

  and to provide signals on a conductor 46 to the counter 30 and to an input of an AND gate 48 with multiple inputs. Another input of the AND gate 48 is connected to a latch circuit 50 itself connected to the detector 26. This latch circuit

  delivers a permanent signal when the detector 26 has de-

  detected a burglary or a predetermined alarm condition

  undermined. The third input of the AND gate 48 is connected

  at one of the output terminals of meter 30. As

  this has been indicated above, the output terminal to the-

  which the AND gate is connected identifies the particular sensor in that in each sensor, the AND gate

  is connected to a different output of the counter.

  It should be noted that the locking circuit 50, the detector 26 and the AND gate 48 are of standard type,

  as well as the pulse detector 44 which can

  take a monostable multivibrator circuit. The detection

  The pulse generator 44 also delivers a quiescent pulse on the conductor 50 to bring it back to rest.

  the counter 30 in response to an elongated pulse de-

  delivered on the conductor 42. The detection of the elongated pulse can be done in the usual manner in the sensor, using a simple capacitor charging circuit with a comparator comparing the voltage

  at the terminals of the capacitor with a predetermined voltage.

2 48 3 10 4

  When the generator 34 emits short pulses, the capacitor can be connected so as to charge and discharge with the series of pulses with an elongated pulse, this capacitor finally reaches the predetermined threshold level and the comparator decays. delivers a resting pulse that is applied to the counter 30O The idle pulse generator is represented by the meter control unit 54 connected to the pulse generator 34 by a driver 56o. simply

  count the number of pulses produced by the

  34 and deliver an elongated pulse on the

  driver 58 after a corresponding number of pulses

  The elongated pulse on the conductor 58 may be applied to the line 42 by the converter 38, using the control unit 40 which detects the presence of the counter. On the line 58, a pulse is made on the conductor 60 toward the counter 32 to return it to rest. The pulse generator 34 may be provided separately or, in devices which use regularly occurring immobilizing pulses, these pulses may themselves be used by

  the pulse detector '44 instead of providing a gen-

  3 separate pulse generator. Impulses of immobilization

  Although they are used elsewhere, they have a dual purpose in that they are used for the zone indicating device as well as for immobilizing all the sensors in order to allow their visual inspection.

24831C4

  -16 when the set has been triggered '. A provision of this

  kind will be described with reference to Figure 5.

  Returning to Figure 2, the output of the AND gate 48 provides a signal, which, when produced, indicates that an alarm condition exists for that particular firer. He is heard hearing the door AND 48

  is opened by the simultaneous appearance of a sigzal in-

  The condition indicator indicates that the latch 50 has a latch impeded by the counter 30 and a pulse on the line 4e. It thus appears that during the cycling of the counter 30, the AND gate 48 is only open once during the period of the

  - cycle and for a period equal to the duration of the

The output signal of gate 48 is brought back via line 64 to control unit 10 in which an alarm signal is detected in detection subassembly 66. of blowout and alarm in the control unit. At the same time, this alarm indicator signal is applied in parallel to a gate terminal LT 68 with two inputs. The other terminal of each gate ET 68

  is connected to a different output of the counter 32.

  Thus, each exit had, ompteuur. is associated with an AND gate and an input of each of these gates receives in paral] el: a signal indicating condition

alarm line 64.

  The simultaneous presence of an alarm indication signal on the line 64 with an output pulse of the counter ú2 produces a pulse t at the output of the corresponding AND gate 68. The ET gate is connected to a corresponding gate circuit 70 and hence to a corresponding indicator device 72.

  22. In u-n mode of

  the sign may simply include a series of light-emitting diodes which are each labeled with a

different sensor.

  In operation, the pulse generator 34 simultaneously delivers pulses to the counters 30

  and 32 so that they progress or advance

  one hundred positions per position, in synchronism. If the counters consist of shift registers,

  each of them has outputs that are authorized

  sequentially so that the AND gates correspond

  the latching circuits and the electroluminescent diodes are sequentially sequenced. At the same time, the counter 30 progresses by the same time and when there is coincidence between a signal of the detector and a counter output signal and an output signal of the sensor pulse sensor the AND gate of the last applies a pulse or another signal on line 64. This signal is detected at the sound detector 20 so that the corresponding AND gate in the control unit is also open and the pulse of the AND gate 68 appears with the simultaneous presence of a signal on line 64 and a particular output counter. As a result, the road sign

  ordered to provide the appropriate indication9

  not only a condition of alarm but also the

  position o the alarm condition has been detected.

  When the counters have progressed in a cycle9 a quiescent pulse is emitted and the cycling

counters start again.

  It should be noted that any type of alarm condition can be detected by the sensor 12 and the fact that an alarm condition exists can be transmitted back on any filde to the control unit. It should also be noted that only existing lines are used because any burglar alarm device includes at least one wire that transmits an alarm condition indication. It is the simultaneous appearance of this alarm condition indication with an output

  the meter which establishes the identity of the

  where the alarm condition has been detected. The alarm conditions may consist of a

  burglary, as detected by the opening of

  on doors, windows, etc., or the signal of

  output of an ultrasonic detector, or the result of

  state of an attempted violation or short circuit.

  Figure 3 shows a device that uses an anti-tamper and anti-short circuit line as one of the alarm lines of the set. In this embodiment, a sensor 80 may include a tamper detector 82 comprising a number of different types of detection circuits. The first of these detection circuits can be the current circuit of

  burglary detection, for example circuits with

  and ultra sound. In a variant O, in addition, a cir-

  Cooking detection may include a circuit that detects the violation or short circuit of the wires. This circuit detects open wires or short circuits between the wires of a cable that connects the sensors together and to the control unit. Moreover, this last circuit can

  detect the short circuit of a sensor.

  It is known that one of the ways to make

  a burglar alarm device consists of short-term

  circuit a given sensor by connecting the upstream and downstream son to the position of this sensor, and eliminating it by cutting the son ends. Several provisions have been proposed to control the state of the wires resulting in a particular sensor, and so

  to control both open and short threads

  circuit, and the state of a wire actually becomes an alarm condition which can be detected and relayed to the control unit The retransmission of a type of alarm indication is by a designation circuit of one which may be similar OR designation circuit 24 of the

  Figure 2o In a model of e realization the signal of exit

  Zone designation circuit 84 is used to block a switching component, shown in FIG.

  present case by a field effect transistor 86 connected

  In one embodiment, the anti-tamper circuit and the anti-tamper circuit are used in series with a casing switch 88 and a resistor 90 in the sensor unit 80. To use

  this wire a contiai current signaling is super-

  posed on the alternative signals normally transmitted by oette! igne and a low-pass filtering is used

  to recover the continuous signals at the control unit.

  The manner of detecting an alarm condition on the june wire will now be described. As shown in FIG. 9, a chain of resistors consists of a resistor R. in the control unit 10, a resistor R2 in the sensor 80 and resistors R3 and 14 in the various other sensors. The resistors R1i9 R2 RHet R4 are connected in series by the connection of the sensors am yellow wire0 The return circuit is established by the ground wire9 the black wire in the present case

  This chain of resistances constitutes a divisor of

  whose common point 92 between the resistors R1 and R2 is connected to an inverting input of a comparator

  94 of type c.arant. The non-inverting input of this compa-

  controller receives an adjustable voltage from a source

  96, by a voltage divider including a potentiometer

  meter 98 and a resistor 100 connected between the source

  96 and the mass. The common point 102 between the potentiometer

  be 98 and the resistor 100 is connected to the input no

aforementioned invertor.

  When ultrasonic sensors are used, a lasing filter 104 is provided to eliminate the effects of an alternating signal produced by an oscillator 106 when the latter is needed to power the detections.

  ultrasonic sounders in the sensors.

  In operation, if an alarm condition is detected at 82 by any appropriate means, the corresponding field effect transistor is blocked by the zone designation circuit 84. This designation circuit of

  zone has an AND gate which delivers a signal

  response to the simultaneous presence of an output signal

  of the burglary detector 82 and a pulse from

  from a pulse generator in the control unit

  In one embodiment, the pulse generator unit is a unit 108 that generates signals.

  control which includes the immobilisation pulses.

  tion. When a particular field effect transistor is blocked, it appears a significant imbalance of

  comparator voltage 94 which triggers the alarm 110.

  The triggering of the alarm 110 is detected by a de-

  zone detector 112 of the same type as the zone detector of FIG. 2 in order to turn on the desired lamp 114 on the traffic sign, indicating the position or the

burglary zone.

  In the case of a short circuit, for example the voltage

  In the event of a short circuit on the yellow wire represented by the dotted line 115, the resistor X2 is eliminated, which causes an imbalance to the comparator 94. An alarm is thus triggered and the traffic sign

  indicates the position of the attempted short circuit.

  The description made above therefore relates to

  to the emission of an alarm signal on one

  wires which is not normally used for this purpose.

   In fact, in the embodiment described, the yellow wire is used to detect a violation and a short circuit while the green wire can be used.

  only to develop signals related to a detection

  break-in. In general, when detecting a burglary, these detectors simply connect the green wire to the ground. This grounding is detected by a main alarm relay 120 in the control unit.

  command 10. This relay triggers alarm 110 and this

  triggering is detected by the zone detector 112 and reported at 114. This therefore constitutes a redundant system in which any type of alarm condition may be indicated on the yellow wire of violation while the current break-ins are detected simultaneously on

the green wire.

  Of course, during the day it can be

  desirable to deteve movements in a given sound and the green wire indication may be interrupted by a switch 122 while the violation of a box

  or a wire during the day is indicated and reported -

  as described. During the night, the switch

  122 is closed and any violation, short-circuit or break-up

  This is indicated by this redundant set.

  According to FIG. 4, and assuming the presence of alternative signals on a line used as an alarm line, an as-passed filter 130 may be interposed in the line, comprising an RC circuit 132, 134. Assuming that instead of being connected to the aforementioned field effect transistors of FIG. 3, the AND gate 48 is connected directly to the line 64 of FIG. 2, and if it is assumed that the iT 48 gate normally delivers a level logic "1" in the absence of break-in and a

  logic level "0" as an indication of a break-in

  paratridge 136 is interposed before directly controlling the AND gates 68 of FIG. 2 by the signal of the sEr gate 48. This comparator is coupled with the signal of the line 64 in that its inverting input receives

  a signal that is the output signal of the pass filter

  step 130. A positive voltage is applied to the inverting input by a resistor 138 so that if the line 64 is not grounded, the inverting input is

at potential V +.

  The non-inverting input of the comparator receives 1/3 V + of a voltage divider consisting of resistors

  and 142 connected between V + and ground. A resistance

  this reaction 144 gives the entire circuit a hysteresis so that if an oscillator signal appears on the line 64, the circuit does not react fast enough, that is to say does not react to the individual cycles of the signal carrier on this line. When the line 64 is grounded, the inverting input goes to 0 volts which is detected by the comparator and an output signal V + is applied to the eI gates 68 as in the case described above. In this way, the alternating signals are completely filtered and the scaling of the line 64 of FIG. 2 is converted into a positive voltage.

  applied to the doors eT 6b of the control unit.

  The device described above is therefore a

  Zone indication system in which the region or zone of a break-in is announced by means of a simple circuit and using only existing wires of a multi-wire cable. This device can be added to any existing burglar detection device so that a burglar

  place can be changed with zone signaling.

  Depending on the type of device used, redundancy

can also be introduced.

  The modification with indication of zone without

  to read separate threads will now be explained. But

  before going on to a detailed description, a type of

  four-wire break-in device

  currently existing will be described in general terms.

  This device comprises a control unit and a

  tain number of sensors connected in parallel on four wires. In one embodiment, each of the sensors comprises an ultrasonic detector controlled by a 26 kHz signal. It should be noted that in one type of device, each sensor has a local indicator which displays the triggering of an alarm and which is used as a visual test indication that the sensor has been locked. The four wires that are used are as follows. Two of the wires are used to provide continuous feed to the sensors; the third wire is used to provide signals at 26 kHz and the

  fourth wire is used for bi-directional control

  and alarm signaling. The 26 kHz signal is used to provide each sensor with a signal to be transmitted in the protected area. The 20 kHz signal supplied to each sensor is reproduced by means of a comparator circuit whose function is to restore the

  signal level at 26 kHz at each sensor.

  is essentially a dc comparator which receives the signal at 26 kdiz from the cable and converts it into each sensor into a rectangular flanked signal

steep.

  The signal line is a bidirectional line and the signals from the control unit to the sensors are voltage level signals which

  command the local display function of each

  tor. These are three-state signals that are used on this line. The highest voltage is used

  to bring back to rest 1 local stall. The voltage

  intermediary is used to allow 1 display

  to lock and stay locked when

  that an alarm condition arises, until it is put to rest by the above-mentioned high voltage. The third, lowest voltage is used to immobilize the local display in the state it is at when the immobilization signal is placed on the wire. The purpose of immobilizing the local display is to allow normal operation of the whole without disturbing the state of the display. In other words, a responsible guard can put the unit in immobilization and then make a round in the protected areas - without modifying the local information displayed and without

  change the normal operation of the rest of the

  tion. Thus, the alarm information Su central station is not affected. The main utility is to locate a problem of false alarm and to allow

  to isolate it to a particular sensor.

  - The alarm information is returned from the sensor on the same wire as the one used for the local display command. The signal back to the control unit consists of a current absorbed by

  this unit whenever a sensor gives the alarm.

  The control unit has a voltage source con-

  connected to the signal wire now the voltage signaling at three levels regardless of the current drawn

  by the control unit on this wire. This allows the cap-

  to produce an alarm signal without disrupting the local display command. When a local alarm is present, the sensor draws a current on the signal wire and this current is detected at the control unit

like an alarm.

  The above-mentioned voltage source comprises a resistor

  control and a comparator. When the voltage source supplies an increasing current to keep the signal line at the correct voltage, this fact is

  detected by a detection resistor and a comparator.

  When this current exceeds a certain value, the comparator triggers an alarm. This current exceeds a

  certain value, the comparator triggers an alarm.

  It should be noted that no current is taken from the line, except for certain bias currents distributed in certain input stages of the comparators but which are currents of very low intensity, of the order of the microampere. In one embodiment, the current drawn during an alarm is determined by the fact that each sensor connects a resistor between the signal line and the ground. The comparator is therefore sensitive

  the current that is taken with the signaling voltage

  lowest when the resistance is connected

  between the line of seats and the door.

  Figure 5 shows that the survreil-

  The above-mentioned remote start has a control unit 200 provided with a power source 202, an oscillator 204 to 26 ICizV of a logic unit 206

  signal line comprising a sensor 208 of

  rant dealarme, and a 2X0 voltage source at three levels. An alarm logic unit 212 is connected to the alarm current detector and an alarm relay 214 is controlled by this alarm logic unit. The

  exits from the power source are made through

  1 and 2 shown, the output of the oscillator 204 is connected to the terminal 3 and the output of the signal line logic unit 206 is connected to the terminal 4. In the unmodified device, a unit 220 is provided. ,

  comprising a three-pole unipolar switch 222

  central opening, whose external contacts

  connected respectively to terminals 6 and 7 of the

  central tee 200, and whose central contact is grounded. A light-emitting diode or other display device 224 is connected to the terminal 5 of the control unit 200. With respect to the indicating device 224, this device is controlled when a signal of

  Alarm condition is received by the control unit.

   Regarding the switch 222, the grounding of the terminal 6 or 7 appears at the terminal

  4 a different level of voltage. With the

  mutator in the position shown, a continuous level representing a level of immobilization is applied to

  4. In the central position, which is the posi-

  stop signals are generated and in the lower position a level of

  put at rest is applied to terminal 4.

  If we now consider one of the sensors of this existing device, the one shown in box 230 includes a motion sensor 232 connected to terminals 1, 2 and 3 for its supply * for ultrasonic signals. The output of the motion sensor is generally connected to a local display lock circuit 234 and to a current receiver 236 which, when it receives an alarm signal, draws a current

  to the signal line as described below.

  In order for such a device to be able to provide a zone indication without using separate wires, the sensor 230 includes a clock pulse detector 240 connected to a synchronization pulse detector 242 which in turn is connected to a binary counter 244. at four bits, the output of the clock pulse detector being also connected via line 246 to the clock control of the four bit binary counter

  and an AND gate 250 with three inputs.

  The output of the binary counter is connected to a

  four-bit amplitude parser 252 which is in turn controlled by a 16-bit binary code switch 254.

  In operation, the pulse detector of hor-

  The box detects the negative transitions of signals on the signal line, corresponding to the beginning of the mobilization pulses that. In this device, the output signal of the clock pulse detector is produced on a periodic basis. This signal is applied to the synchronization pulse detector which detects a long mobilization pulse for restoring the four-bit binary counter to rest. the signals from the clock pulse detector are directly applied to the binary counter for the progressive progress. It should be noted that the clock pulses detected by the pulse detector 240 are applied as clock pulses to the counter. 244 by the line 246, the signal from the synchronization sensor 242 synchronizing nnd being provided only when a long pulse of the immobillisationo appeared. The comparator of amplitude 254 4 bits works in the suirvanteo way When the output of the binary counter to 4 bits equals the code that is set by the 16-bit binary code switch, an output signal is issued on line 256 to the door

  ET 250. The other input of the AND gate 250 receives a

  output signal of the local display lock 2.:14 circuit, the appearance of which indicates that an alarm has occurred at the sensor. This signal is applied on the line

260 to the ET gate 250.

  At the simultaneous reception by the AND gate 250 of a clock pulse which is in the form of the normal immobilization pulses periodically produced by an output signal of the comparator cd 4-bit amplitude and a signal of condition d alarm, this door úJT 250 is opened to draw a current at the terminal 3 of the sensor. This produces a negative voltage

  superimposed on the signal at 26 ktz from the signal line.

  This result is obtained by means of a resistance 262 of kohms between the terminal 2 and the terminal 3 of the control unit, and a resistance 264 of 1 kilobim between the output of the gate El '250 and the terminal 3 of the sensor. It thus appears that an alarm condition signal is

  now available, not only on the line of

  at terminal 4 of the control unit, but also

  on the 26 kHz line at terminal 3 of the control unit

  of. The device complementary to the control unit for the wireless zone indication separates on local display 300 is connected as shown at terminals 1, 2

  and 3 of the initial CPU. Unit 220 is eliminated

  and terminals 5, 6 and 7 of the control unit are

  connected respectively to terminals 4, 5 and 6 of the

  local display 300. It should be noted that the local display 300 has 6 terminals and is connected to 6 terminals of the control unit. Although it is often convenient to locate the local display near the control unit, it should be noted that according to an additional feature, this local display unit can be connected in any

  point of the set insofar as a 6-wire cable

  ductors is available between it and the control unit.

  This may only require the installation of 3 additional cables to the control unit because the other 3 cables are normally used as can be seen next to the 4-conductor interconnection cable between

  the control unit and the sensors.

  The power of the local display unit 300

  is provided by its terminals 1 and 2 to a source of food.

  302 inside the unit. So. terminals 1 and 2 of the local display unit are connected to the

  terminals 1 and 2 of the control unit.

  Terminal 3 of the local display unit is connected to

  at terminal 3 of the control unit and it is

  used to detect alarm condition signals.

  For this purpose, a pulse detector 304 is connected

2483 1 0 4

  at terminal 3 of the local display and it is used to detect negative transitions of voltage

  on the line at 26 kHz. This is done in the usual way

  using filtering circuits and

  thresholds. The output signal of the detector 304 is applied on line 306 to an addressable register 308 controlled

  by a bit counter 310 of 4 bits of a similar nature.

  to that of the 244 4-bit binary counters

  sensors. The outputs of the addressable register are

  to a zone display device 312 to 15 light-emitting diodes. The local display unit is controlled by a clock 314 at 1 Hz, with a pulse ratio of 10%. The clock output 314 controls a 3-bit bit counter 3'10 and is also connected to the addressable register. The output of the bit counter 310 is connected to an AND gate 316 with 4 inputs which produces the synchronization pulse, i.e., the elongated immobilization pulse. The latter is applied on the line 310 to an OR gate 322. The output of the clock circuit is also applied on a line 324 to the OR gate 322, the output of which leads to the terminal. 5 of the local display unit, connected to terminal 6 of

  the control unit. This is the line of momentum impulses. The emission of regular impulses

  ge on the command immobilization pulse line

  the voltage source has three levels to produce

  get voltage level immobilization impulses

  low on a regular basis, these impulses

  sation being the clock pulses for the 4-bit binary counters of the sensors. It appears as well as the 4-bit binary counters of the local display and

  sensors are simultaneously controlled by the im-

immobilization impulses.

  The local display unit 300 also includes a local display control switch which produces

  signals for resting, locking or immo-

  bilisation. This switch is shown schematically at 330. The output of this switch is connected to an interface circuit 332. Normally the switch 300

  local display control is in lock position

  lage. In this position no signal is applied to terminal 6 and the immobilization pulses which are

  the clock pulses are transmitted from the

  local hut at terminal 5, to terminal 6 of the

  control for the sequential control of the sensors.

  When the rest of the installation has to rest at rest, the connector 330 is set in such a manner that the terminal 0 is at the rasse. but the mass is suppressed when the output of the OR gate 322 is at

  low so that the clock pulses continue

  nu to be produced on the signal wire. When it is necessary to immobilize the installation, the switch

  330 is placed in a position of immobilization which in principle

  cipe immobilizes the clock 314. When this is so, a permanent synchronization pulse is produced, resting all the counters at rest. On the waveforms shown at the bottom and

  the right of Figure 5, the reference A designates an imnpul-

  immobilization, the reference b a clock pulse, the reference C of the locking signals,

  the reference D of the pulses of resting, the re-

  E is a synchronization pulse, the reference F is a clock pulse and the reference G is a data pulse. These waveforms show that initially

  a long immobilization impulse A brings the compo-

  resting. It is followed by a level C signal

  lock itself followed by a clock pulse.

  ge B, followed by another lock level signal C

2483 104

  lage. It should be noted that short impulses of

  are produced up to the moment when 16 of them have been produced, and at that moment an impulse

  synchronization circuit E consisting of a dimmable pulse

  elongated bilization is produced. The device can be brought to rest at any time by a rest signal. As shown in FIG. 1, the idle signal D is momentarily interrupted by pulses.

  The reason why the impulses of hor-

  can overcome the pulse of resting is that it is necessary to maintain the clock rate of all

  oompteu.rsq while restoring the display register to

  local chage Regarding immobilization impulses,

  why they are chosen as hor-

  overall, they do not restore the local display to rest and do not significantly disturb the visual control of the equipment, as long as they

  are kept relatively short compared to the fono-

  perception of the local display indicator. The

  why negative transitions of

  are used for the clock pulse is that the initial protocol chosen for the signal line uses

  negative pulses to immobilize the display.

  Temporary fixed assets of the local display do not interfere in any way with the visual control

  as long as they are maintained at

* rs of the order of 100 ms, as shown in the diagram

of time.

  It should be noted that the synchronization signal E is used to bring back to rest the counters which

  serve for display without the use of separate wire.

  In addition, the separate wireless zone display operates independently of the local display lock and is used to remotely give an indication of the state of this lock without disrupting the previous functions that were set in the initial setup. The idle pulse DJ has the function of restoring the local display lock. In this embodiment, it is a continuous level used to bring the local display lock back to rest while the synchronization pulse E is used to return the counters used to

  the separate wireless zone indication. The impulse of syn-

  The chronization appears once every 16 clock pulses and restores the meters to ensure that even if a parasitic pulse has been received in the installation, it does not interfere with the operation.

  remote displays for more than one

  clock stage. So each cycle of the binary counters

  is reset to zero to start again each cycle.

  A feature of the adaptation of the separate wireless zone indication to the device described above is that the immobilization signal can be used in

  more than one goal. Initially the immobilization signal

  tion was used to immobilize the whole of the

  for a control round to be made.

  In this case, the immobilization signal is still

  re used for the same purpose. But by pulsing this signal, it can now be used as clock pulses for the separate wireless zone indication

  without altering the normal operation of the previous unit

  toothed. This means that even if the display lock is

  chage is brought back to rest, impulses of immobilisation

  tion do not change the procedure for resetting the local display lock, nor the visual reading during a control round. Another feature of this addition is that if the area indication is not needed in a given case, the old sensors can be connected independently of any zone indication. This is because the initial immobilization, locking and quitting functions are not disturbed, irrespective of the fact that, in the locked state, there is momentarily a return to the immobilization level and irrespective of the

  that during resting, it occurs moment-

  a return to the immobilization level.

  10.In summary, older sensors that can be connected to the line in a local display lockout situation do not respond to signals that are placed on the lines to produce the identification of

separate wireless zone.

  FIG. 6 represents a 4-wire installation capable of fulfilling not only more developed alarm and security functions, but also of analog data transmission collected at a remote location, to the control unit O.

  a control unit 400 comprises the source of

  tion 402, the 404-level voltage source 404, an oscillator 406 at 26 IkHz and a second

  voltage source 408 at three levels, conrectes

  1, 2, 3 and 4 of the control unit 400 The control unit 4 is also connected to a signaling current detector 410 which is connected via an analog-to-digital converter. 411 to a microprocessor interface circuit 412. This interface circuit includes

  control lines to the voltage source 404 to 3 ni-

  the oscillator 406 and the voltage source 408 to

  3 levels. In one embodiment, the circuit for

  The microprocessor interface has a capacity of 8 bits in each direction, to and from a microprocessor 414 connected to the display device 416. In one embodiment

2483-104

54-,

  the microprocessor 414 is an Intel 8080 model.

  The control unit is connected to a number of cir-

  sensor interface / control interface, one of which is

  shown schematically at 420. The sensor has 4 input terminals, as shown, which connect to the sensor the ground lines and V + as well as the control signal lines. The sensor terminal 3 is connected to a high signal detector 422 and a detector

  424 low signal level whose outputs are connected

  respectively to EnT gates 425 and 427 and thence to terminals "1" and "0" of a trackable circuit 426, connected itself to a relay 428. EL gates 425 and 427 are controlled by an output signal from the address counter 442 as will be explained later, when the sensor 420 is addressed. At its turn, the relay 428 is connected to a local device for operation or use 430. It should be noted that the operation of the

  corresponding device is controlled by the signalisa-

  this particular relay. The latter can be used for example to put in. walk and stop engines, lamps, etc.

  The signal line at terminal 4 of the inter-

  sensor face is connected to a pulse detector 440.

  positive clocking whose output is connected to

  the clock input of an address counter 442. The de-

  The positive clock pulse detector is connected to a quiescent pulse detector 444 which responds to the aforementioned elongated pulse so as to return the appropriate counter to sleep. The output of the counter 442 is connected to an ST gate 446 via a

  connection pin positioned appropriately.

  The other input of the AND gate 446 is connected to a negative clock pulse detector 448 connected

  itself to the signal line through terminal 4 of the sensor.

  in operation the positive clock pulses

  The events are detected at 440 and counter 442 operates accordingly. A pin connected to a predetermined output, corresponding to the address of the capture interface circuit connects the output of this counter

  at. the 444 door When the counter 442 counted

  than the value indicated by this connection pin,

  the particular sensor has been addressed. Cinsuites if it appears

  a negative clock pulse on the signal line, it is detected at detector 448 and

  simultaneous output of a counter 442 with the de-

  If a control unit wants to read this particular sensor and if it wants to read more than one data type in the particular sensor address and the positive clock pulse, then one of the control units wants to read that particular sensor. It is maintained at the input of the UT gate 446 and a series of negative clock pulses are then generated for the output of the gate 446 to advance the auxiliary counter. It should be noted that one way of maintaining the positive clock input at gate 446 is simply to inhibit the clock pulses by returning the clock pulse signal to zero for the required time. This is recognized by the clock pulse detector as the

  immobilizer counter 442, so that a signal lo-

  high level is available when it is immovable

  bilisé. This high level logic signal is applied to

door L1T '446.

  As the figure shows, the auxiliaure counter

  450 performs a number of different functions.

  In the first case, it can indicate that an alarm condition has been detected at 452, locked at 454 and combined by a function i1T at 456 with a count coming from the counter that is applied to an OR gate 460 as an indication. that an alarm condition has arisen. It should be noted that when the counter 450 is brought to rest, its zero output is high. Thus, any alarm condition detected and locked causes the application of a signal to the door

  01 460. Then, if it is desirable to be able to

  roger the sensor to determine what type of alarm it is or on what basis it was produced, a connection pin can be connected between an output of the auxiliary meter 450 and one of the input terminals of the door OR 460. For example, if this sensor is an anti-theft sensor rather than a fire sensor, a single pin is placed between the appropriate meter output and an OR 4L60 input. Thus, the type of alarm condition can be detected after this alarm condition has occurred if a second signal from the OR gate coincides with a

  predetermined pulse of the auxiliary counter.

  The output signal of the door Ou 460 is applied

  A current converter 462 may be substantially any type of controlled current source which draws current from the signal line to the control unit. The current drawn from

  this way is detected in 410 and it is applied com-

  me input signal to circuit 412 micro-interface

  processor. As will be explained hereinafter, this signal is correlated in time with states of the microprocessor registers indicating the address of the sensor at which an alarm condition has occurred, and the

  type of alarm condition it represents.

  If it is necessary for the sensor to detect

  In view of a number of local analog conditions, the counter may progress beyond the alarm detection count to positions, in this case 9 to 12, selectively operating switches 470, 472 and 474 to apply detected analog data. to a current voltage converter 476 for the purpose of

  their retransmission to the control unit.

  With regard to now the control unit 400, it should be noted that the 3-level voltage source 404 can produce 3 signals of different levels as indicated by the curve of the line C at the bottom of this

  The function of one of these signals is to control

  In the present embodiment, this line C transmits a 26-line centered reotangular carrier centered at a level of about 095 V + o, ie, half of the supply voltage V + appearing at terminal 2 of the control station. The presence of this carrier centered around 095 V% is the state of rest of the signal. The 404 voltage source at 3 levels goes to

  high level to set the relay lock.

  The high level signal is centered around 098 V and is detected by the high level detector 422 which latches the relay latch. This energizes the relay for the desired control function. voltage centered around 0.2 V + is applied to line C and the relay drops back. As regards signaling on the S-line, the signal is also produced by a 3-level voltage source, but the control functions are quite different. On the waveform of line S, immediately above the waveform of line C

  in the figure the reference A designates a positive pulse

  at rest of addresses the reference B of the impulse

  Positive address clock, the reference C

  negative pulse of data quiescence, the ref-

  V is the transmission of a zero data bit, the reference of the negative data clock pulses and the reference to the transmission of a four bit of data. This waveform therefore shows that positive and

  negative are used as clock pulses.

  The positive pulses are used for the address counter and the negative pulses for the auxiliary counter. Elongated positive or negative pulses are used

  as pulses of resting while impulses

  are used as impulses of hor-

lodge for these meters.

  fln operation, a positive impulse A of setting

  at rest is applied on line S, for example

  64 ms. It brings to rest all the counters of

  dresses of all the sensors. When the elongated positive quiescent pulse becomes negative, which occurs for about 4 ms, data corresponding to the zero zone if it exists can be returned to the signal line. Then, after a dead time, which in this case is 4 ms, a clock pulse

  which corresponds to the address of the first sensor is

  on the S line. In this case # this clock pulse lasts 2 ms. Then there is a time-out

  -4 ms after the production of the first positive impulse

  At this time, data can be received on the S-line. A series of positive pulses is generated until a particular sensor is addressed which information is to be received. At this moment, an elongated negative pulse of

  rest is applied to line S and then, impulses

  Negative clock pulses are applied as described above for the auxiliary counter, allowing: J reading of data determined by one or more

  connection pins. The data is read between the

  of negative clock pulses, during the in-

  time of 4 ms. But in the case of analog data transmission, this period may be too short. In order to allow transmission of analog data, positive clock pulses may be inhibited to introduce as many negative clock pulses as necessary. Then, the negative pulses can be selectively inhibited

  to allow the transmission of analog data.

  The interval of 4 ms between the pulses of the clock po-

  and negative is usually a minimum interval

  The device can therefore work in two ways.

  res. First, clock pulses at predetermined intervals are emitted, with negative pulses interposed between two positive clock pulses without inhibiting the latter. In variance an individual sensor can be addressed by producing a separate sensor. given number of clock positive pulses, then the latter are inhibited until all the necessary data have been read in

  sensor- The first case corresponds to a sampling -

  of all the sensors while the second case corresponds

  to a sensor addressing followed by a reading of all

  the data that is needed. For example, while in the general case, an interval between

  positive pulses can last up to 5 ms to accept

  the worst case, if a more efficient device is needed in which some sensors do not need this time for output information,

  the interval between the pulses can be shortened.

  It should be noted that the signaling device described above allows the transmission and reception of a large amount of data on 4 wires. It should also be noted that there is a large number of sensors although there is usually only one control unit per set. It is therefore important to realize the sensor as efficiently as possible so that the largest amount of data can be retransmitted and the widest variety of environmental situations.

can be accepted.

  Of course, many modifications can be made by those skilled in the art to the embodiments described and illustrated by way of examples in no way

  limiting without departing from the scope of the invention.

2483 104

Claims (14)

  1- D) ispositif indication of zone intended for   multiple sensors and an interconnecting cable with   between a monitoring position and a monitored position, characterized in that it comprises a control unit (10) comprising a   (32) producing output signals, one for each   counting, and a device (34) that advances   said counter with a first group of pulses of   and simultaneously applying said clock pulses to said multi-wire cable, and a sensor   (12) connected to said interconnecting cable to said po-   monitored version, said sensor comprising a corresponding counter (.0) connected so as to progress under the effect of the first group of clock pulses applied to said multi-wire cable, so that said counters progress simultaneously with said first   group of clock pulses, said counter corresponding to   outputting sensor, one for each count, said sensor further comprising a device (26) producing a signal carrying information under the effect of a predetermined condition and a device   (48) responsive to a selected one of said output signals   to control said sensor to apply said signal carrying information on said multi-wire cable for transmission to said control unit, said control unit (10) comprising a transmission responsive device (68, 70); said signal carrying information by said cable to several   wire and at a corresponding output of the meter in detecting   both the presence of said signal carrying information and   its content, the position of the emitting sensor being deter-   undermined by the meter status of the control unit at   when said signal carrying information is transmitted set to said control unit.   2- Device according to claim 1, characterized in that said control unit (200) comprises a device (206) for applying on said multi-wire cable a control signal as a function of the detection of said signal bearing information, said sensor (230) having a device (234) which detects said control signal and which produces an actuation signal in response to the detection of said   control and prior control of said sensor.   3- Device according to claim 1, characterized in that said detection device (234) reacts to the   simultaneous transmission of said signal carrying information   and corresponding output signal of the counter of said control unit.   4- Device according to claim 1, characterized in that said control unit (400o) conmporte a device (408) for producing a second group of clock pulses interposed between the pulses   the first group, said second group of pulses   which can be distinguished from the first group   eg, said sensor (420) having a second counter (450) connected to said multi-wire cable and responsive to the actuation of said sensor and said second group of clock pulses producing output signals for each of said counts, said sensor comprising a   device (476) which produces said signal carrying a   training in response to the appearance of an output signal   predetermined amount of said second counter so that a   said first counter (442) of the sensor identifies said sensor as the activated sensor and that the second counter of said sensor determines the information that is transmitted, - Device according to claim 4, characterized in that said detection device responds to said output corresponding counter to said control unit followed by the transmission of said information-carrying signal in the interval between two neighboring pulses of said first group of clock pulses 6.The device according to claim 5, characterized in that it further comprises a device ( 412) to said control unit, intended to immobilize the production   implants of said first group of clock pulses   age 9 so that a time can be left for the   transmission of information from a pre-sensor   determined 7- Device according to claim 1, characterized in that said control unit normally produces   a signal intended for all sensors, said normal signal   being applied to said multi-threaded cable   standard being amended to form first group of clock pulses.   8- Device according to claim 7, characterized.   in that said normal signal provides a current to said sensors, said modification consisting in producing in   same time voltage pulses.   9- Device according to claim 4, characterized in that said control unit normally produces   a signal intended for all the sensors 9 applied to the-   said multi-wire cable, said signal: normal being   modified in different ways to form said first   first and second groups of control pulses.   - Device according to claim 9, caraote   in that said normal signal provides a current   to the sensor, the said modification consisting of   derive peaks of positive or negative voltages depending on which group of clock pulses is produced.   11- Device according to claim 2, characterized   in that said control signal contains a   amplitude offset in a predefined direction   born for a predetermined control function.   12- Device according to claim 1, characterized   characterized in that said control unit comprises a device (54) for producing a quiescent pulse after each counter cycle, said quiescent pulse having a duration longer than any pulse of said first group of quiescent pulses. clock, a device (38) applying said setting pulse   resting on the same wire as that on which   first group of clock pulses is applied while at the same time eliminating said first group of pulses   clock of said wire, said sensor comprising a device   tif (44) connected to said same wire for detecting said idle pulse and for restoring the sensor counter to the detection of said pulse of put to rest.   13- Device according to claim 1, characterized   said signal carrying a trans-   puts the information in the form of the intensity of a current on one of the wires of said multi-wire cable, said   control unit comprising a device (410) which   it monitors the current intensity on said wire.   14- Device according to claim 13, characterized   in that said sensor comprises a device (452)   for detecting an alarm condition and a device   tif (462) responsive to the detection of said condition   alarm by connecting to the ground the wire on which the   Current tense is controlled.   Device according to claim 13, characterized   characterized in that said sensor comprises a device (470-474) which monitors a predetermined condition and a device (476) which sets the intensity of said current   according to said monitored condition.   16- Device according to claim 1, characterized   in that said sensor is arranged to detect   an alarm condition and includes a display device   local display (430) for displaying the appearance of   said alarm condition, said display being latch-   on the occurrence of said alarm condition and devel-   scrambled at the appearance of a predetermined level of one   clock pulses of the first group.   17- Device according to claim 16, characterized   in that said control unit carries a dis-   positive which inhibits the appearance of said predetermined level   in order to allow a visual inspection of the display   local chage of a sensor without disturbing the progression   normal by clock and the other operations of said sensor.   18- Device according to claim 1, characterized   in that each sensor comprises a terminal panel with a number of pairs of terminals, a device for connecting a terminal of each pair to an output signal of a corresponding counter of said sensor a connection device of said operating device to all the other terminals of said pairs, and an interconnection pin placed between the associated terminal with said selected output signal and with the other terminal of the pair, so that the sensor can be easily adjusted to react to a count given by the set up the connection pin.   19- Method of indicating zone to the control unit   in a device monitoring device   taking a central control unit in a position   connected by a multi-wire cable with multiple   in a number of different positions, O30 so as to establish the sensor which retransmits information to the control unit without adding additional cable, characterized in that it   consists essentially of mounting meters in the   control unit and in the sensors, to simul-   all counters, to operate each sensor according to a different counting of the counter in order to retransmit information from   the sensor when it is activated, and to mount a   the control unit to establish the counter status of the control unit at the time of reception of the retransmitted information, thus making it possible to establish   the identity of the activated sensor that transmits the information.