EP0063876A1 - Système d'alarme et un module de détection pour celui-ci - Google Patents
Système d'alarme et un module de détection pour celui-ci Download PDFInfo
- Publication number
- EP0063876A1 EP0063876A1 EP82301785A EP82301785A EP0063876A1 EP 0063876 A1 EP0063876 A1 EP 0063876A1 EP 82301785 A EP82301785 A EP 82301785A EP 82301785 A EP82301785 A EP 82301785A EP 0063876 A1 EP0063876 A1 EP 0063876A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- alarm
- module
- zone
- sensor
- central controller
- 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.)
- Withdrawn
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Classifications
-
- 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
- G08B25/04—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 a single signalling line, e.g. in a closed loop
-
- 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
- G08B25/014—Alarm signalling to a central station with two-way communication, e.g. with signalling back
-
- 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
-
- 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
- G08B29/06—Monitoring of the line circuits, e.g. signalling of line faults
- G08B29/08—Signalling of tampering with the line circuit
-
- 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
- G08B29/12—Checking intermittently signalling or alarm systems
- G08B29/14—Checking intermittently signalling or alarm systems checking the detection circuits
Definitions
- the present invention relates to an alarm system.
- a previously proposed alarm system is described in an article "Microprocessor-Based Alarm Reporting and Display System" by J.B. Morgan of Vindicator Corporation, Santa Clara, California, (Proceedings of 1978 Carnaham Conference on Crime Countermeasures).
- the described system comprises up to 2000 alarm sensors connected, in groups, to up to 250 transponders.
- the transponders are connected to a common multiplex data bus and are sequentially addressed by a central controller.
- the described system is a digital system, is expensive, and more suitable for large installations having hundreds of transponders rather than for smaller installations with say tens of transponders at most.
- an alarm system capable of monitoring a plurality of zones, the system comprising a respective sensor module (7) in each zone, each module being connected to, and arranged to monitor, at least one associated alarm sensor (1-6) in its respective zone, the system also comprising a central controller (9) and being characterised in that each sensor module (7) is connected to the central controller (9) by a respective two-way signalling path (8), and is capable, on the one hand of storing an alarm indication produced by its associated alarm sensor or sensors and, on the other hand, of signalling said indication to the central controller (9) via said respective signalling path (8); the module (7) also including means, selectively actuable by the central controller (9) via said respective signalling path (8), to visually indicate in each zone, whether the module (7) in that zone remains capable of responding to an alarm indication.
- a sensor module (7) suitable for use in an alarm system characterised by the module (7) including store means (43) capable of storing an alarm indication produced by a connected alarm sensor (1-6) and also including display means (73), selectively actuable by a central controller (9), to display whether said store means continues being capable of responding to an alarm indication.
- the sensor module may further comprise means selectively actuable by the central controller to set and unset settable alarm sensors.
- the sensor module may yet further comprise means capable of identifying an alarm indication distinctive of differing alarm sensors, and signalling said alarm indication to the central controller.
- the shown intruder alarm system can . monitor eight zones of t'or example a builning. This may oe utilized particularly for an intruder alarm system but is not restricted thereto, for example fire sensors may be utilized.
- each zone there is at least one detector, 1...6 connected to a zone module 7.
- zone 5 has two zone modules 7 and two detectors 5 and 6 and monitoring of zone 6 and 7 is not shown for reasons of clarity.
- the zone modules 7 are connected by respective four core cables 8 to a central controller 9.
- a power supply 10 supplies power to the central controller and to active or electronic detectors such as detectors 3 and 5 which require a power supply.
- the central controller 9 receives indications from the detectors 1 to 6 via the zone modules 7, of whether or not any of the detectors have sensed an intrusion in any of the zones, and also sends signals to the zone modules to achieve various functions which will be described hereinafter.
- the controller sequentially scans the zones and only thereby can identify which zone is indicating an intrusion.
- the controller can also be arranged to detect whether the detector giving an alarm in any one zone is a raid detector or not from the nature of the signal it receives from a zone module as will be described hereinafter.
- Zones 1 and 8 can include either or both a shunt lock 16, which enables an-authorised person to pass through the access zone without generating an alarm and a local shunt switch 17 which enables a localised area to be switched off.
- zone 5 where there are two or more zone modules, they are connected in series as shown in Figure 2.
- the continuity of the four cores of successive portions of the cable 8 is maintained by wires within each zone module so that removal of any one module breaks the continuity.
- the actual circuits of the zone modules are connected in parallel with the continuous cable portions 8.
- the controller is able to detect breakage of continuity due to removal of a zone module and signal an alarm condition in response thereto.
- Figure 1 shows only one detector per zone module 7, more than one detector may be connected to each module 7 as shown for example in Figure 3, which will be described in more detail hereinafter.
- each zone module 7 has: an input/output arrangement 71 having two ports for connection to a detection loop 30, and two power supply ports for powering an active detector; an arrangement 72 having two ports for connection to a raid loop 37; and an LED display 73 positioned to be visible to an observer.
- the module accepts inputs from three types of alarm contact at the input/output arrangement 71 for the detection loop. They are:
- an active detector powered from the power supply ports of the input/output arrangement 71 has two normally closed contacts 32 and 33, whilst the loop 30 also includes passive normally closed contacts 34 and 36 and a passive normally open contact 35.
- the active detector having contacts 32, 33 may comprise an ultrasonic detector such as 5
- the normally closed contacts 34 and 36 may comprise a window foil such as 4
- the normally open contact 35 may be a pressure detector such as 6.
- a raid loop 37 comprises a series of two normally closed contacts 38 and 39 equivalent to raid switch 2 of Figure 1 for example.
- the nature of the signal received by the controller from a zone module can identify the type of detector giving the alarm.
- a booster circuit which is operational only if the alarm sensor connected is a raid loop. The functioning of this particular module will become clear hereinafter.
- Alarm contacts can be either:
- diodes D33 and D36 shunt normally closed contacts 33 and 36 whilst diode D35 is in series with normally open contact 35.
- Such contacts 33, 35 and 36 are settable and unsettable by choosing the direction of current flow around the loop 30.
- the zone module 7 accepts three signals from the controller 9. They are:
- the zone module indicates to the controller:
- the controller is connected to a zone module 7 (or a series of modules 7) via a four core cable 8.
- the four cores are designated:
- the alarm line from the controller is terminated by an end of line resistor EOL having in the example a resistance of 6K8 connecting the alarm line to the common ground.
- EOL end of line resistor
- the alarm line connects within the controller 9 to a +12V supply via a 1K resistor, and to a set of comparators 20.
- the comparators in effect, sense the total resistance in series with the 1K resistor, by comparing the voltage V A on the alarm line with reference voltages.
- a zone module effectively connects both a 1K resistor and a 4K7 resistor in parallel with the EOL resistor, and other alarms are indicated by connecting a 4K7 resistor in parallel with the EOL resistor.
- the controller can reset a latch circuit of a zone module by reducing the +12V source voltage of the alarm line to 0 volts for a period of between 200ms and 1 second as will be apparent hereinafter.
- the controller can also send signals to the zone module(s) 7 via the control line, which as will be apparent hereinafter have an effect as follows:-
- control line goes open circuit or short circuit to ground the zone module acts as if it has received the Set signal.
- a current monitor in the zone module becomes inoperative and signals an alarm.
- the control line is connected to a Set-Unset detector 40 which controls a voltage reversal circuit 41 to cause current to flow in the alarm detection loop (e.g.loop 30 of Fig.3) in a direction defined by the voltage on the control line, to set or unset the alarm contacts in the loop.
- a voltage reversal circuit 41 to cause current to flow in the alarm detection loop (e.g.loop 30 of Fig.3) in a direction defined by the voltage on the control line, to set or unset the alarm contacts in the loop.
- a current monitor 42 monitors the current flowing in the detection loop 30 by monitoring the current flowing from the +12V line to the reversal circuit 41.
- the current is limited by an end of line resistor EOL (6K8) and the internal resistances of the voltage reversal circuit 41 and the monitor 42.
- EOL end of line resistor
- the monitor 42 causes a latch circuit 43 to operate and connect a 4K7 resistor from the alarm line to the ground line.
- this change of alarm line resistance is sensed by the central controller to indicate an alarm condition.
- a raid input detector 44 is connected to for example the raid loop 37 of Figure 3. If a normally closed contact 38 or 39 is opened due to an intrusion, a 1K resistor is connected from the alarm line to the ground line by the detector 44. Furthermore the latch circuit 43 is also operated by the detector 44 to connect the 4K7 resistor to the ground line. The controller senses the resultant alarm line resistance as a raid condition.
- the zone module 7 further comprises the LED73 which is driven by an LED drive 45.
- The. drive is controlled by the latch 43 and by a display mode detector 46, which is responsive to the control line voltage, via an AND gate 47.
- the controller If the controller emits the enable display voltage and at the same time an alarm condition is indicated by the latch 43, the LED will emit light.
- the zone module also comprises a normally closed anti-tamper switch 48 which is in series with the detection loop to cause an alarm if for example, the housing (not shown) of the zone module is removed.
- the latch circuit Once the latch circuit has been actuated to indicate an alarm it is deactuated by the central controller 9 reducing the +12V source voltage on the alarm line to zero for 200ms to 1 second, the latch circuit being powered from the alarm line via connection 49.
- the zone module thus allows the following five modes of operation to be achieved for a zone module of one zone, assuming one zone module per zone.
- All contacts associated with the module are enabled and can cause the latch 43 and the controller to indicate an alarm condition. No display of the alarm condition is required at the zone module to avoid warning an intruder that an alarm has been set off.
- the display of the zone module is enabled by the controller and if an alarm contact is actuated so that the associated latch circuit 43 indicates the alarm condition, the associated display 73 locally indicates the alarm. All settable/unsettable alarm contacts in other zones are unset by the controller to inhibit them. Thus the zone module of the actuated alarm displays the alarm, but other alarms in other zones are inhibited by the controller so as to allow a search for the alarm source to be made without setting off the other alarms. This mode also allows easy checking for faulty alarms.
- the controller is caused to continuously cycle through the set, display and reset modes if an alarm contact is deliberately.operated to test it.
- the zone module provides local indication of the operation of the contact but no alarms are signalled by the controller.
- the latch circuits 43 can be reset by removing the power supply to the alarm line.
- the set/unset detector 40 comprises a transistor 40 the base of which is connected to the control line via a potential divider R1, R2 to receive the set/unset signal from the controller 9.
- the transistor In the set condition, the transistor is non conductive, and in the unset condition it is conductive.
- the voltage reversal circuit 41 comprises six CMOS inverting amplifiers (eg a4069 circuit) in a single IC package having a common power line 50.
- the amplifers are connected as shown to produce a direction of current flow in the detection loop 30 defined by the set/unset detector 40.
- the current monitor 42 monitors the current flowing in the power line 50 to the reversal circuit 41.
- the current flowing in the power line is limited by resistors R3, R4 of the monitor 42, by resistors R7 and R8 at the outputs of the reversal circuit and by the 6K8 end of line resistor of the detection loop.
- transistor T2 of the monitor 42 is non-conductive and transistor T1 is conductive.
- transistor T1 becomes non-conductive.
- the raid input detector 40 which is connected to the raid loop 37 comprises a transistor T3 the base of which is connected to a potential divider R11, R12, R13 between the +12V line and the ground line as shown.
- the raid loop shorts out resistors R12, R13 so that transistor T3 is non-conductive and the voltage at point B is +12V derived from the alarm line via the 1K resistor.
- transistor T3 In an alarm condition the raid loop is open-circuit, transistor T3 is conductive and the voltage at point B is zero volts and the 1K resistor is effectively in parallel with the 6K8 end of line resistor EOL (see Fig.4 or Fig.2) to signal a raid alarm to the controller 9.
- the latch circuit 43 comprises four NAND gates in a common IC package having a common power line 49 (eg a4093 circuit).
- the power is derived from the alarm line via a smoothing and clamping circuit comprising a resistor R14, a Zener diode D2 and a capacitor C1.
- the gates are connected as shown to form a bistable latch circuit.
- Resistor R15 and capacitopr C2 in one of the feed back connections of the bistable define a minimum time required for an alarm condition to actuate the bistable.
- the bistable is set so that the 4K7 resistor is connected from the alarm line to ground via the low impedance output of one of the gates, to signal an alarm condition to the controller 9.
- both the 1K and the 4K7 alarm resistors are connected between the alarm line and ground. For other alarms only the 4K7 resistor is so connected.
- the display mode detector comprises a transistor T4, the base of which is connected to a potential divider R16, R17, R18 between the control line and ground.
- a diode 47 is connected between the potential divider and the bistable to act as the AND gate 47.
- bistable circuit does not indicate an alarm, but the controller emits the display enable signal on the control line, the diode 47 conducts, the conduction path extending to ground through the low impedance output of the gate to which it is connected and thus transistor T4 is non-conductive. If the bistable circuit indicates an alarm, diode 47 is non conductive and the transistor T4 is conductive, and LED 73 is then enabled.
- the bistable As the bistable is powered from the alarm line, it can be reset by reducing the alarm line source voltage to OV.
- a booster circuit operational for raid loop connections must be incorporated.
- a raid or detection loop 37 or 30 is connected to the voltage reversal circuit 41. If an alarm is detected then as before the voltage at point A will drop to zero volts, which will be sensed by latch circuit 43 to connect the 4K7 resistor from the alarm line to ground via the low impedance output of one of the latch circuit gates, to signal an alarm condition to the controller.
- a raid switch RS is linked to a point C connected to diode 47, which point increases in voltage when an alarm condition is registered.
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- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Computer Security & Cryptography (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Alarm Systems (AREA)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB8112051 | 1981-04-16 | ||
GB8112051 | 1981-04-16 |
Publications (1)
Publication Number | Publication Date |
---|---|
EP0063876A1 true EP0063876A1 (fr) | 1982-11-03 |
Family
ID=10521208
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP82301785A Withdrawn EP0063876A1 (fr) | 1981-04-16 | 1982-04-05 | Système d'alarme et un module de détection pour celui-ci |
Country Status (1)
Country | Link |
---|---|
EP (1) | EP0063876A1 (fr) |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1987001226A1 (fr) * | 1985-08-19 | 1987-02-26 | Per Axel Uhlin | Installation de surveillance |
WO1988007245A1 (fr) * | 1987-03-18 | 1988-09-22 | Carl Erik Starefoss | Systeme d'alarme, de securite et de sauvetage combines |
WO1989007304A1 (fr) * | 1988-01-27 | 1989-08-10 | Messerschmitt-Bölkow-Blohm Gesellschaft Mit Beschr | Procedure a suivre et dispositif pour la protection contre les catastrophes naturelles et la pollution |
EP0562960A1 (fr) * | 1992-03-27 | 1993-09-29 | Cegelec | Appareil de surveillance et d'alarme pour installation de contrôle/commande |
AT399957B (de) * | 1986-05-16 | 1995-08-25 | Merk Gmbh Telefonbau Fried | Gefahrenmeldeanlage |
EP0874342A2 (fr) * | 1997-04-22 | 1998-10-28 | Deutsche Telekom AG | Procédé de différenciation dans le traitement des signaux d'alarme |
US9589436B2 (en) | 2015-05-26 | 2017-03-07 | Google Inc. | Systems and methods for announcing location of unauthorized party |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1503894A (fr) * | 1966-10-18 | 1967-12-01 | Alarme Et Telesurveillance A T | Perfectionnements aux installations électriques d'alarme et de surveillance |
DE2407267A1 (de) * | 1974-02-15 | 1975-08-28 | Merk Gmbh Telefonbau Fried | Schaltungsanordnung fuer alarmanlagen mit gleichstromgespeisten linienleitungen |
FR2293018A1 (fr) * | 1974-11-26 | 1976-06-25 | Saab Scania Ab | Dispositif de surveillance centralise |
GB1529947A (en) * | 1976-07-09 | 1978-10-25 | Munford & White Ltd | Ultra-sonic intruder alarms |
US4138674A (en) * | 1977-02-22 | 1979-02-06 | Contronic Controls Limited | Four wire multi-satellite intrusion alarm control system with tamper switch |
GB2022301A (en) * | 1978-05-30 | 1979-12-12 | American District Telegraph Co | Intrusion detection system |
-
1982
- 1982-04-05 EP EP82301785A patent/EP0063876A1/fr not_active Withdrawn
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR1503894A (fr) * | 1966-10-18 | 1967-12-01 | Alarme Et Telesurveillance A T | Perfectionnements aux installations électriques d'alarme et de surveillance |
DE2407267A1 (de) * | 1974-02-15 | 1975-08-28 | Merk Gmbh Telefonbau Fried | Schaltungsanordnung fuer alarmanlagen mit gleichstromgespeisten linienleitungen |
FR2293018A1 (fr) * | 1974-11-26 | 1976-06-25 | Saab Scania Ab | Dispositif de surveillance centralise |
GB1529947A (en) * | 1976-07-09 | 1978-10-25 | Munford & White Ltd | Ultra-sonic intruder alarms |
US4138674A (en) * | 1977-02-22 | 1979-02-06 | Contronic Controls Limited | Four wire multi-satellite intrusion alarm control system with tamper switch |
GB2022301A (en) * | 1978-05-30 | 1979-12-12 | American District Telegraph Co | Intrusion detection system |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO1987001226A1 (fr) * | 1985-08-19 | 1987-02-26 | Per Axel Uhlin | Installation de surveillance |
AU592597B2 (en) * | 1985-08-19 | 1990-01-18 | Per Axel Uhlin | Surveillance installation |
US4929927A (en) * | 1985-08-19 | 1990-05-29 | Uhlin Per A | Surveillance installation |
AT399957B (de) * | 1986-05-16 | 1995-08-25 | Merk Gmbh Telefonbau Fried | Gefahrenmeldeanlage |
WO1988007245A1 (fr) * | 1987-03-18 | 1988-09-22 | Carl Erik Starefoss | Systeme d'alarme, de securite et de sauvetage combines |
AU594869B2 (en) * | 1987-03-18 | 1990-03-15 | Carl Erik Starefoss | Combined alarm, security and rescue system |
WO1989007304A1 (fr) * | 1988-01-27 | 1989-08-10 | Messerschmitt-Bölkow-Blohm Gesellschaft Mit Beschr | Procedure a suivre et dispositif pour la protection contre les catastrophes naturelles et la pollution |
EP0562960A1 (fr) * | 1992-03-27 | 1993-09-29 | Cegelec | Appareil de surveillance et d'alarme pour installation de contrôle/commande |
FR2689279A1 (fr) * | 1992-03-27 | 1993-10-01 | Cegelec | Appareil de surveillance et d'alarme pour installation de contrôle/commande. |
EP0874342A2 (fr) * | 1997-04-22 | 1998-10-28 | Deutsche Telekom AG | Procédé de différenciation dans le traitement des signaux d'alarme |
EP0874342A3 (fr) * | 1997-04-22 | 2000-05-17 | Deutsche Telekom AG | Procédé de différenciation dans le traitement des signaux d'alarme |
US9589436B2 (en) | 2015-05-26 | 2017-03-07 | Google Inc. | Systems and methods for announcing location of unauthorized party |
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Legal Events
Date | Code | Title | Description |
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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 |
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AK | Designated contracting states |
Designated state(s): DE GB NL |
|
17P | Request for examination filed |
Effective date: 19821111 |
|
17Q | First examination report despatched |
Effective date: 19860801 |
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STAA | Information on the status of an ep patent application or granted ep patent |
Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN |
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18W | Application withdrawn |
Withdrawal date: 19870204 |
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RIN1 | Information on inventor provided before grant (corrected) |
Inventor name: DE CROOS, JAYE Inventor name: BLACK, ALEXANDER PATRICK Inventor name: O'BRIEN, BRIAN EDWARD NICHOLAS Inventor name: SAMPSON, MARTIN STUART |