Security alarm is a system designed to detect unauthorized intrusions - into a building or other area. Security alarms are used in residential, commercial, industrial and military properties for protection against robbery (theft) or property damage, as well as personal protection against intruders. Security alarms in residential areas show a correlation with the theft decline. Car alarms also help protect the vehicle and its contents. The prison also uses a security system to control prisoners.
Some alarm systems serve one purpose of robbery protection; Combination systems provide fire protection and intrusion. Intrusion alarm systems can also be combined with closed circuit television surveillance (CCTV) systems to automatically record intruder activity, and possibly an interface to access control systems for electrically locked doors. Systems range from small, independent, to complicated multiarea makers with computer monitoring and control. It may even include a two-way voice that allows communication between the Monitoring panels and stations.
Video Security alarm
Design
The most basic alarm consists of one or more sensors to detect intruders, and devices that remind to show intrusion. However, public place security alarms use the following components:
- Local control unit (PCU), Alarm Control Panel (ACP), or just panel : "Brain" of the system , it reads sensor input, tracks arm/disarm status, and signal intrusion. In modern systems, these are usually one or more computer circuit boards inside a metal enclosure, along with a power supply.
- Sensors : Devices that detect interruptions. Sensors can be placed around a protected area, inside, or both. Sensors can detect intruders with a variety of methods, such as monitor doors and windows to open, or by monitoring unfilled interiors for movement, sound, vibration, or other disturbances.
- Warning device : This indicates an alarm condition. Most commonly, these are bells, sirens, and/or flashing lights. The warning device serves the dual purpose of residents warning of disturbance, and potentially scaring thieves. This device can also be used to alert the occupants of fire or smoke conditions.
- Keypads : Small devices, usually mounted on walls, that serve as a human-machine interface to the system. In addition to buttons, the keypad usually displays indicator lights, small multi-character display, or both.
- Interconnection between components. This may consist of a direct cable to a control unit, or a wireless link with a local power supply.
In addition to the system itself, security alarms are often combined with monitoring services. If there is an alarm, the control unit will contact the central monitoring station. The operator at the station sees the signal and takes appropriate action, such as contacting the property owner, notifying the police, or sending personal security forces. Such signals can be transmitted through special alarm circuits, telephone lines, or the internet.
Maps Security alarm
Sensor type
The reed switch ends in silence
Closed reed switches are a very common type of two-piece sensor that operates with a conductive electric grass switch that is normally open or normally closed when under the influence of a magnetic field as in the case of proximity to a second piece containing a magnet. When the magnet is removed from the reed switch, the reed switch either closes or opens, again based on whether or not the design is normally open or normally closed. This action coupled with an electric current (usually at 12V DC) allows the alarm control panel to detect errors in the zone or circuit. These types of sensors are very common and found either wiring directly to the alarm control panel, or they can usually be found in wireless doors or window contacts as sub-components.
Passive infrared detector
Passive infrared motion detector (PIR) is one of the most commonly found sensors in household and small business environments. It offers affordable and reliable functionality. The term passive refers to the fact that the detector does not produce or radiate its own energy; it works entirely by detecting the heat energy released by other objects.
Actually, PIR sensors do not detect motion; instead, they detect sudden temperature changes at a certain point. When an intruder walks in front of the sensor, the temperature at that point will rise from room temperature to body temperature, and then back again. This fast change triggers detection.
The PIR sensor may be designed to be mounted on a wall or ceiling, and comes in a variety of fields of view, from a narrow point detector to a 360-degree field. PIRs require a power supply other than a signaling detection circuit.
Infraound detector
The infrasound detector works by detecting infrasions, or sound waves at frequencies below 20 hertz. Sound at that frequency is not heard by the human ear. Due to its inherent nature, infrasions can travel hundreds of kilometers away. Infrasound signals can be generated from volcanic eruptions, earthquakes, gravitational waves, opening and closing doors, forcing windows to name a few.
The entire infrasound detection system consists of the following components: speakers (infrared sensors) as microphone inputs, order-order filters, analog to digital converter (A/D), and finally an MCU, which is used to analyze the recorded signal.
Whenever a potential intruder attempts to enter a house, he or she tests whether it is closed and locked, using the tool at the opening, or/and applying pressure, and therefore he creates a low-frequency sound vibration. The action is immediately detected by infras detectors before intruders intrude.
The main purpose of the system is to stop thieves before they enter the house, to avoid not only theft, but also vandalism. Sensitivity can be modulated depending on the size of the house and the presence of animals.
Ultrasonic detector
Using frequencies between 15 kHz and 75 kHz, this active detector transmits ultrasonic sound waves that are not heard by humans. The principle of Doppler shifting is the underlying method of operation, where the frequency change is detected due to the movement of the object. This is caused when the object must cause an ultrasonic frequency change to the receiver relative to the transmission frequency.
The ultrasonic detector operates by the emitter transmitting the ultrasonic signal to the area to be protected. Sound waves are reflected by solid objects (such as floors, walls, and surrounding ceilings) and then detected by the receiver. Because ultrasonic waves are transmitted through the air, objects with hard surfaces tend to reflect most of the ultrasonic energy, while soft surfaces tend to absorb most of the energy.
When the surface is stationary, the frequency of the wave detected by the receiver will be equal to the transmitted frequency. However, a change in frequency will occur as a result of the Doppler principle, when a person or object moves in or away from the detector. Such events trigger alarm signals. This technology is considered obsolete by many alarm professionals, and is not actively installed.
Microwave detector
This device emits microwaves from the transmitter and detects any reflected microwave or reduced emission intensity using the receiver. Transmitters and receivers are usually incorporated in a single housing (monostatic) for indoor applications, and a bistatic for outdoor applications. To reduce false alarms, this type of detector is usually combined with a passive infrared detector, or a Dual Tec brand or similar alarm.
The microwave detector responds to the Doppler shift in the frequency of reflected energy, by phase shift, or by a sudden drop of the received energy level. One of these effects may indicate an intruder movement.
Compact monitoring radar
Compact surveillance radars emit microwaves from transmitters and detect any reflected microwave. They are similar to microwave detectors but can detect the exact location of an intruder in an area that extends over hundreds of acres. With the ability to measure reach, angle, speed, direction, and target size, CSR can determine the exact GPS coordinates of intruders. This target information is usually displayed on maps, user interfaces, or situational awareness software that defines geographic zones or geographies with different types of actions that start depending on time and other factors. CSR is typically used to protect outside the frontline of critical facilities such as electrical substations, power plants, dams, and bridges.
Photoelectric rays
The photoelectric ray system detects the presence of intruders by transmitting visible or infrared light in an area, where these blocks may be blocked. To increase the surface area of ​​detection, blocks are often used in two or more stacks. However, if an intruder is aware of the existence of the technology, it can be avoided. This technology can be an effective remote detection system, if installed in a pile of three or more in which the transmitter and receiver stumble to create a barrier like a fence. The system is available for both internal and external applications. To prevent clandestine attacks using a secondary light source used to hold the detector in closed condition while the intruder passes through, most systems use and detect modulated light sources.
Break-break detection
The break-glass detector can be used for internal perimeter building protection. The glass-cork acoustic detector is installed near the glass panel and listen to the sound frequency associated with broken glass.
Seismic glass-break detectors, commonly referred to as shock sensors, are different because they are mounted on a glass panel. When the glass breaks, it will generate a special shock frequency that moves through the glass and often through the window frame and the surrounding walls and ceilings. Typically, the most intense frequencies are generated between 3 and 5 kHz, depending on the type of glass and the presence of the plastic interlayer. The glass-break seismic detector senses this shock frequency and in turn generates an alarm condition.
Window foil is a less sophisticated, mostly obsolete detection method that involves plating a thin strip of conductor foil on the inside of the glass and placing low-power electrical current through it. Solving glass is practically guaranteed to tear the foil and break the circuit.
Smoke detector, heat, and carbon monoxide
Most systems are also equipped with smoke, heat, and/or carbon monoxide detectors. This is also known as the 24 hour zone (which is always on). Smoke and heat detectors protect against fire risk using different detection methods. The carbon monoxide detector helps protect against the risk of carbon monoxide poisoning. Although the intruder alarm panel may also have this detector connected, it may not meet all of the local fire code requirements of the fire alarm system.
Traditional smoke detectors are technically an ionization smoke detector that creates an electric current between two metal plates, which sounds an alarm when disturbed by the smoke entering the room. Ionization smoke alarms can quickly detect small amounts of smoke generated by a rapidly burning fire, such as cooking fire or being propelled by paper or flammable liquids. The newer, and probably safer, type is the photoelectric smoke detector. It contains a light source in a light-sensitive electrical sensor, positioned at an angle of 90 degrees to the sensor. Normally, the light from the light source radiates straight and passes through the sensor. When smoke enters the room, it diffuses the light, which then touches the sensor and triggers the alarm. The photoelectric smoke detector usually responds more quickly to the fire in the early stages, smoldering - before the source of the fire explodes into a blaze.
Motion sensor
Motion sensors are devices that use different forms of technology to detect motion. Technologies typically found in motion sensors to trigger alarms include infrared, ultrasonic, vibration and contact. The dual sensor technology combines two or more forms of detection to reduce false alarms because each method has its advantages and disadvantages. Traditionally, motion sensors are an integral part of home security systems. This device is usually installed to cover a large area because it usually covers up to 40 ft with a 135 Â ° field of view.
Driveway alarm
The entrance alarm system can be tied to most security and automation systems. They are designed to alert citizens to unexpected visitors, intruders, or shipments arriving at the property. They come in a choice of magnetic and infrared sensing. Inlet alarms can also be purchased in wired and wireless systems. They are common in rural security systems as well as for commercial applications.
Vibration (shaker) or inertia sensor
This device is mounted on obstacles and is used primarily to detect attacks against the structure itself. This technology relies on an unstable mechanical configuration that forms part of the electrical circuit. When movement or vibration occurs, the unstable circuit part moves and breaks the current flow, which produces an alarm. Device technology varies and can be sensitive to different levels of vibration. Medium that emit vibrations must be properly selected for special sensors because they are most suitable for different types of structures and configurations.
This type of sensor is somewhat new and has not been proven using piezo-electric components rather than mechanical circuits, which can be set to be very sensitive to vibration.
- Advantages: Highly reliable sensor, low false alarm rate, and midpriced.
- Disadvantages: Must be installed on the fence. A rather high price hinders many customers, but its effectiveness offsets the high price. The piezo-electric sensor is a new technology with unproven records compared to mechanical sensors that in some cases have field records of more than 20 years.
Passive magnetic field detection
This buried security system is based on the principle of magnetic anomaly detection operation. The system uses an electromagnetic field generator that is supported by two cables running in parallel. Both cables run along the perimeter and are usually installed about 5 "/12 cm above the wall or about 12"/30 cm underground. The cable is connected to a signal processor that analyzes every change in the magnetic field.
These buried safety system sensor cables can be planted at the top of virtually any wall type to provide regular wall detection capability, or can be buried in the ground. They provide a very low false alarm rate, and have a very high chance of detecting the actual thief. However, they can not be installed near high voltage lines, or radar transmitters.
E-field
This proximity system can be mounted on the perimeter of buildings, fences, and walls. It also has the ability to be mounted freely on dedicated poles. This system uses an electromagnetic field generator that drives one wire, with another wire wire running parallel to it. Both cables run along the perimeter and are usually installed about 800 millimeters apart. The sensing cable is connected to the signal processor that analyzes:
- changes in amplitude (mass of intruders),
- change of exchange rate (intruder movement),
- time of preset interruption (time of intruder in pattern).
These items determine the characteristics of the intruder and when all three are detected simultaneously, an alarm signal is generated.
Barriers can provide protection from the ground up to about 4 meters in height. These are usually configured in a zone about 200 meters long depending on the number of installed sensor cables.
- Advantages: hidden as buried form.
- Disadvantages: expensive, shorter zones which mean more electronics (and thus higher costs), and a high false alarm rate because it can not distinguish some pets from humans. In reality it does not work well, because extreme weather can often cause false alarms.
Microwavers
- Advantages: low cost, easy installation, invisible perimeter barrier, and unknown perimeter limit for intruders.
- Disadvantages: very sensitive to weather; such as rain, snow, and fog, for example, will cause the sensor to stop working, and require sterile perimeter lines because trees and shrubs or anything that blocks the rays will cause false alarms or lack of detection.
Microphonic System
Microponic systems vary in design but each is generally based on intruder detection attempting to cut or climb chain fences. Usually a microphone detection system is installed as a sensor cable attached to a rigid chain fence, but some special versions of this system can also be installed as a system buried underground. Depending on the selected version, it can be sensitive to different levels of noise or vibration. This system is based on a coaxial or electro-magnetic sensor cable with a controller that has the ability to distinguish between signals from cables or cut-off chainwire, fence-climbing intruders, or adverse weather conditions.
The system is designed to detect and analyze incoming electronic signals received from the sensor cables, and then generate alarms from signals that exceed predetermined conditions. The system has electronics that can be customized to allow the installer to alter the sensitivity of the alarm detector according to certain environmental conditions. System settings are usually performed during commissioning of detection devices.
- Advantages: very cheap, configuration is very simple, and easy to install.
- Disadvantages: some systems have a high false alarm rate because some of these sensors may be too sensitive. Although systems using DSP (digital signal processing) will largely eliminate false alarms in some cases.
Wire fence system
The fast wire perimeter security system is basically an independent screen of tightened tripwires that are usually installed in fences or walls. Or, the screen can be made so thick that no chain fence is required. The system is designed to detect any physical effort to break through the barrier. The fast wire system can operate with various switches or detectors that feel movement on each end of a tense wire. This switch or detector may be a simple mechanical contact, a static-style transducer or an electronic tension gauge. Unwanted alarms caused by birds and other animals can be avoided by adjusting the sensor to ignore objects that provide small amounts of pressure on the cable. This type of system is vulnerable to intruders digging under fences. Concrete footing directly under the fence is installed to prevent this type of attack.
- Advantages: low-level of false alarms, highly reliable sensors, and high detection rates.
- Disadvantages: very expensive and complicated to install.
Fiber optic cable
Fiber-optic cables can be used to detect intruders by measuring the difference in the amount of light sent through the fiber core. If the cable is interrupted, the light will 'leak' and the receiver will detect a difference in the amount of light received. Cables can be attached directly to a wire fence or tied into a spiked steel tape used to protect the top of walls and fences. This type of spiked ribbon provides a good physical barrier and provides immediate warning if the tape is cut or highly distorted. The other types work on the detection of polarization changes caused by fiber position changes.
- Advantages: very similar to a microponic system, very simple configuration, and easy to install.
- Disadvantages: high false alarm rate or no alarm at all for systems that use light leaked out of optical fibers. Polarization change systems are much more sensitive but false alarms depend on alarm processing.
H-field
This system uses the principle of electro-magnetic field disturbance based on two coaxial cable without cover (or 'leaking') buried about 10-15 cm and located about 1 meter. The transmitter radiates radio Frequency (RF) energy continuously along the length of one cable and energy is received by another cable. When a change in field strength weakens due to an object and reaches a predetermined threshold, an alarm condition is generated. The system is unobtrusive when properly installed, but care should be taken to ensure the surrounding soil offers good drainage to reduce alarm interference.
- Advantages: hidden as buried form.
- Disadvantages: may be affected by RF interference, high false alarm rate, difficult to install.
Electrical security fence
The safety of the electric fence consists of a cable carrying an electric current pulse to provide a non-lethal shock to prevent potential intruders. Damaging the fence also generates alarms recorded by the electric fence security guards, and can also trigger sirens, strobe, and/or notifications into the control room or directly to the owner via email or phone. In practical terms, a security electric fence is a type of sensor arrangement that acts as (or part of) a physical barrier, a psychological barrier to potential intruders, and as part of a security alarm system.
- Advantages: cheaper than many other methods, less likely to provide false alarms than many other alternative perimeter security methods, and the highest psychological deterrent of all methods.
- Disadvantage: potential unwanted shock.
Wired, wireless, and hybrid systems
The trigger signal of each sensor is transmitted to one or more control unit (s) either via cable or wireless means (radio, line carrier, infrared). Cable systems are convenient when sensors (such as PIRs, smoke detectors, etc.) require external power to operate properly; however, they may be more expensive to install. The entry-level cabling system utilizes a star network topology, where panels are logically centered, and all home devices run their line cables back into the panel. More complex panels use a Bus network topology where the wire is essentially a data loop around the perimeter of the facility, and has a decrease for the sensor device that must include a unique device identifier integrated into the sensor device itself (eg Biscuit Id). The cable system also has the advantage, if properly connected, to be tamper-evident.
Wireless systems, on the other hand, often use battery-powered transmitters that are more easily installed and have lower initial cost, but can reduce the reliability of the system if the battery is not maintained. Depending on the distance and construction materials, one or more wireless repeaters may be required to get a signal to the alarm panel reliably. Wireless systems can be moved to new homes easily, an advantage for those who rent or move frequently. A more important wireless connection for security is the connection between the control panel and the monitoring station. The wireless monitoring of the alarm system protects against thieves who cut the cable or from the failure of the internet provider. This complete wireless setup is usually referred to as 100% wireless.
Hybrid systems use wired and wireless sensors to achieve the benefits of both. Transmitters can also be connected via a power supply circuit to transmit encoded signals to a control unit (line operator). Control units typically have separate channels or zones for thieving and fire sensors, and better systems have separate zones for each different sensor, as well as internal noise indicators (power loss, low battery, disconnected wire, etc.).
Connection and alarm monitoring
Depending on the application, the alarm output may be local, remote or combination. Local alarms do not include monitoring, although they may include indoor and/or outdoor sounds (eg motorized bell or electronic siren) and lights (eg strobe lights) that may be useful for alerting evacuation notices to people during fire alarms, or where one hope to frighten amateur thieves quickly. However, with the widespread use of alarm systems (especially in cars), false alarms are very frequent and many urban people tend to ignore alarms rather than investigate, let alone contact the necessary authorities. In short, there may be no answer at all. In rural areas where nobody hears a fire bell or a thief siren, the lights or sounds may not make much of a difference, because the nearest emergency respondent may be late to avoid losses.
Remote alarm systems are used to connect control units to pre-defined monitors, and they come in a variety of different configurations. High-end systems connected to the central station or first responders (eg Police/fire/medical) via direct telephone cable, cellular network, radio network (ie GPRS/GSM), or IP lines. In the case of multiple signaling systems, these two options are used simultaneously. Alarm monitoring not only includes the sensor, but also the transmitter of the communication itself. While direct telephone circuits are still available in some areas of the phone companies, due to the high cost and the appearance of dual signals with their relatively lower cost being unusual. Direct connections are now usually seen only in federal, state, and local government buildings, or on campus schools that have security, police, fire department or special medical emergency departments (in UK communications only possible to the alarm receiving center - direct communication to the service emergency is not allowed).
A more typical system incorporates a digital cellular communication unit that will contact the central station (or some other location) via the Public Switched Telephone Network (PSTN) and raises the alarm, either by synthesizing sound or progressively through the encoded message string that becomes the center of the decode station. It may be connected to a regular telephone system on the system side of the demarcation point, but it is usually connected on the customer side in front of all the phones inside the monitored location so that the alarm system can seize the line by cutting off the active call and call the monitoring company if necessary. The dual signal system will increase the alarm wirelessly via radio (GPRS/GSM) or cellular lines using the phone line or broadband channel as backup to overcome any compromise to the telephone line. The encoder can be programmed to show which particular sensor is triggered, and the monitor can show the physical location (or "zone") of the sensor on the list or even a protected spot map, which can make the resulting response more effective. For example, a heat sensor alarm, coupled with a fire detector in the same area is a more reliable indication of an actual fire than just one or another sensor indication by itself.
Many alarm panels are equipped with backup communication lines for use when the primary PSTN circuit does not work. The redundant dialer may be connected to a second communication line, or a dedicated mobile phone device, radio, or Internet interface encoded to bypass PSTN completely, to prevent accidental interference with the phone line. Just the fact that someone destroying the channel can trigger an alarm oversight over the radio network, giving early warning of an imminent problem (eg burning). In some cases, remote buildings may not have PSTN telephone service, and the cost of extracting and running a direct connection may be expensive. It is possible to use a mobile device or wireless radio as the primary communication method.
In the UK the most popular solutions of this type are similar in principle to the above but with the primary path and back upside up. Utilizing radio channels (GPRS/GSM) as the main signaling path not only faster than PSTN but also enables substantial cost savings because unlimited amount of data can be sent at no additional cost.
Broadband alarm monitoring
Increased deployment of voice over IP (VoIP) technology is driving the adoption of broadband signaling for alarm reporting. Many sites that require alarm installations no longer have conventional phone lines (POTS), and alarm panels with conventional dialer phone capabilities do not work reliably over some types of VoIP services.
An analog dial-up alarm panel or system with serial/parallel data ports can be migrated to broadband by the addition of an alarm server device that converts the telephone signal signal or data port traffic to the corresponding IP messages for broadband transmission. But the direct use of VoIP (POTS port at the venue terminal) to transport analog alarms without alarm server devices is problematic because the audio codecs used across the network transmission line can not guarantee an acceptable level of reliability or acceptable service quality for the application.
In response to a changing public communications network, new alarm systems can often use broadband signaling as an alarm transmission method, and manufacturers include IP direct reporting capabilities in their alarm panel products. When the Internet is used as a primary signaling method for critical security and life-safety applications, surveillance messages are often configured to address concerns about backup power for network equipment and signal delivery times. But for typical applications, connectivity concerns are controlled by normal surveillance messages, sent every day or every week.
Various IP Alarm transmission protocols exist but the most widely used ones today are proprietary. Just like the format used for conventional, standardized and published telephone reporting, broadband signaling for alarm reporting is being standardized today. In 2007, US alarm manufacturers developed an open standard called DC-09. This standard has been accepted as the American National Standard, and published as ANSI/SIA DC-09-2007. [ref: ANSI/SIA DC-09-2007] This protocol provides coding schemes and transport mechanisms to carry data from 17 pre-defined alarm protocols, including recent Contact IDs, SIA DC-03 protocols and SIA 2000. [ref: ANSI/SIA DC-07-2001.04] Some panel and receiver manufacturers will reportedly develop or have released support for DC-09.
Double signal radio alarm
Double signaling is an alarm transmission method that uses cellular phone networks and telephone and/or IP lines to send high-speed intruders, fire and personal attacks from shelter to the Alarm Reception Center (ARC). It most often uses GPRS or GSM, a high-speed signaling technology used to send and receive 'packets' of data, with phone lines in addition. IP options are not often used because of problems with installation and configuration because of the high level of IT expertise often required in addition to alarm installation knowledge.
A dual signal communication device is attached to the control panel on the security installation and is the component that transmits the alarm to ARC. This can be done in a variety of ways, through GPRS radio channels, via GSM radio channels or via phone line/or IP if selected. These dual signal paths are all present and live at the same time mutually supportive to minimize exposure of property to intruders. If one fails there is always one form of backup and depends on the selected manufacturer up to three lines working simultaneously at one time. Before the availability of a dual signal system, police and key holders were often called into place due to an alarm signal on the telephone line only to find that it was a network error and not an original alarm
The dual path allows the difference between hardware failure and the original attack on the alarm. This helps eliminate false alarms and unnecessary responses. Multiple signaling has been very helpful with the recovery of the Police response as in the case where the telephone line is cut off because the dual signal device can continue to send alarm calls through one of its alternate paths either confirming or denying an alarm from the initial path.
In the UK, CSL DualCom Ltd pioneered dual signaling in 1996. Thus, the company offers the first credible alternative to existing alarm signals when setting the current standard for professional double track security monitoring. Double signals are now firmly regarded as the standard format for alarm signaling and are determined by all leading insurance companies.
Alarm monitoring listen
Monitor the alarm and the speaker phone allows the central station to talk to the owner of the house or intruder. This may be beneficial to the owner for a medical emergency. For the real break-in, the speakerphone lets the central station push the intruder to stop and stop because the response unit has been sent. Monitoring of a listening alarm is also known as a Direct Audio-Response monitoring or Alarm Speaking System in the UK.
Alarm monitoring service
The list of services to be monitored at Central Station has been expanded over the last few years to include: Access Control; CCTV Monitoring; Verify Alarm; Environmental Monitoring; Monitoring Intrusion Alarm; Fire Alarm & amp; Sprinkler Monitoring; Monitoring of Critical Conditions; Monitoring of Medical Responses; Monitoring Elevator Phone; Hold-Up or Panic Alarm Monitoring; Duress Monitoring; Test Auto Dialer; Open & amp; Close Signal & amp; Reporting; Exception Reports; and PIN or Password Code Management. Increasingly, Central Station makes this information available directly to end users via the internet and a secure log-on to view and create custom reports on these events on their own.
Alarm response
In the United States, police respond to at least 36 million alarm activations annually, with an estimated annual cost of $ 1.8 billion.
Depending on the zone being triggered, the number and sequence of zones, the time of day, and other factors, the alarm monitoring center can automatically initiate various actions. The central station operator may be instructed to call an emergency service immediately, or to first contact the protected place or property manager to try to determine whether the alarm is genuine. The operator can also start calling the list of phone numbers provided by the customer to contact someone to go check the protected places. Some zones may trigger calls to a local heating oil company to check the system, or call to the owner with details of spaces that may get flooded. Some alarm systems are associated with video surveillance systems so that the current video from the intrusion area can be directly displayed on the remote monitor, not to mention recorded.
Some alarm systems use real-time audio and video monitoring technology to verify the validity of the alarm. In some municipalities across the United States, this type of alarm verification allows protected properties to be placed on a "verified response" list, allowing faster and safer police responses.
The first home video security system patented on December 2, 1969 for its inventor Marie Brown. This system uses television surveillance.
Access control and code cut
To be useful, an intrusion alarm system is disabled or reconfigured when authorized personnel are present. Authorizations can be indicated in various ways, often with a key or code used in the control panel or remote panel near the entry. High security alarms may require a lot of code, or fingerprints, badges, hand geometry, retinal scans, encrypted response generators, and other means deemed safe enough for that purpose.
A failed authorization must generate an alarm or at least lock in a timed manner to prevent an experiment with possible code. Some systems can be configured to allow the disabling of sensors or individual groups. Other people can also be programmed to cut or ignore individual sensors (once or several times) and leave the rest of the armed system. This feature is useful for allowing one door to be opened and closed before an alarm is armed, or to allow someone to leave, but not to return. High-end systems allow multiple access codes, and even allow them to be used only once, or on certain days, or only in combination with other user codes (that is, escorted). In any case, the remote monitoring center should regulate the spoken code to be provided by the authorized person if there is a false alarm, so the monitoring center can be ascertained that further alarm responses are not required. Like access codes, there may also be an oral code hierarchy, for example, for a furnace repairman to enter the kitchen and basement sensor area but not a silver vault in the pantry. There is also a system that allows the coercion code to be entered and silence the local alarm, but it still triggers a remote alarm to call the police to the robbery.
Fire sensors can be isolated, meaning that when triggered they will not trigger the main alarm network. This is important when smoke and heat are intentionally produced. The owner of the building can be fined for generating false alarms that wasted the time of emergency personnel.
Alarm is wrong and does not exist
The US Department of Justice estimates that between 94% and 98% of all alarm calls to law enforcement are false alarms.
System reliability and user error is the cause of most false alarms, sometimes called "intrusion alarms". False alarms can be very costly for local governments, local law enforcement, security system users and members of the local community. In 2007, the Justice Department reported that in just one year, false alarms harmed local municipal authorities and their constituents were at least $ 1.8 billion.
In many cities across the United States, policies have been adopted for homeowners and businesses both for some false alarm activation of their security systems. If multiple false alarms from the same property remain, the property can even be added to the "no response" list, which prohibits sending police to the property except in a verified emergency. About 1% of police alarm calls actually involve crime. Alarm interference occurs when an unwanted event generates an alarm status by a working alarm system. False alarms also occur when there is a system alarm malfunction that generates an alarm status. In all three circumstances, the source of the problem should be discovered and corrected immediately, so that the respondent will not lose confidence in the alarm report. It is easier to know when there is a false alarm, because the system is designed to react to that condition. Fault alarms are more troublesome because they usually require periodic testing to ensure the sensor is working and the correct signal goes into the monitor. Some systems are designed to detect problems internally, such as low or dead batteries, loose connections, telephone circuit problems, etc. While previous disturbance alarms can be triggered by minor annoyances, such as insects or pets, newer alarm models have the technology to measure the size/weight of objects that cause interference, and thus can decide how serious the threats are, which are very useful in burglar alarms.
Reduction of false alarm
Many cities across the United States require alarm verification before police are sent. With this approach, the alarm monitoring company must verify the validity of the alarm (except for hacking, coercion, and panic alarm) before calling the police. A verified response typically involves in-place visual verification of piercing, or remote audio or video verification.
Home and business owners can now choose a new type of button control panel designed to help reduce false alarms.
Under a standard called CP-01-2000, developed by the American National Standards Institute and Security Industry Association, the new generation keypad control panel takes aim at user error by building extra precautions that minimize unwarranted emergency deliveries.
Some features of CP-01 keypads include a progress annunciation function that emits different sounds over the last 10 seconds of delay, which accelerates out of place. Also, the time out doubles if the user disables the pre-warning feature.
Other "rules" overcame the failure to exit, which resulted in arming all zones in Fixed Mode and once, automatic restart of the exit delay. However, if there is an error out, the local alarm will sound.
Audio and video verification
Alarms that utilize audio, video, or a combination of audio and video verification technology provide company security, dispatchers, police officers, and property data managers more reliably to assess the alarm threat level triggered.
Audio and video verification techniques use microphones and cameras to record audio frequencies, video signals, or image snapshots. The source audio and video stream is sent through a communication link, usually an Internet protocol (IP) network, to the central station where the monitor takes pictures through proprietary software. The information is then forwarded to law enforcement and recorded to an event file, which can be used to plan a more strategic and tactical approach of a property, and then as a proof of prosecution.
An example of how this system works is when a passive infrared or other sensor is triggered a number of designated video frames from before and after an event is sent to the central station.
The second video solution can be incorporated into the standard panel, which sends the alarm center station. When a signal is received, a trained monitoring professional accesses an on-premises digital video recorder (DVR) via an IP link to determine the cause of activation. For this type of system, the camera input to the DVR reflects the zone and the alarm panel partition, which allows personnel to search for alarm sources in some areas.
The US Department of Justice stated that a law that requires an alarm company to verify the validity of the alarm, before contacting law enforcement (commonly known as "verified response") is the most effective way to reduce false thief alarms. The Justice Department considers the audio, video, or eyewitness accounts to verify the validity of a burglar alarm.
Cross-sizing
Cross-zoning is a strategy that does not require a new keypad. Using multiple sensors to monitor activity in one area, the software analyzes input from all sources. For example, if a motion detector moves in one area, the signal is recorded and the central station monitor notifies the customer. The second alarm signal - received in the adjacent zone in a short period of time - is a confirmation that the central station monitor needs to promptly request the shipment. It builds increased protection and fails safely to have the door open or birds swinging the exterior window.
Enhanced call verification
Enhanced call verification (ECV) helps reduce fake shipments by 25-50% while still protecting citizens, and mandated in some US jurisdictions, even though the alarm industry has managed to oppose it in other countries. ECV requires central station personnel to try to verify alarm activation by making at least two phone calls to two phone numbers of the responsible parties before sending law enforcement to the scene.
Call verification-first alarm goes to location of origin alarm. If contact with someone is not done, the second call is placed to a different number. The secondary number, dictate best practice, should be to the answered phone even after business hours, preferably the decision maker's mobile phone authorized to request or cut off the emergency response.
ECV, because it can not confirm the actual intrusion events and will not require priority shipping law enforcement, is not considered a verification of the correct alarm by the security industry.
Independent certification
Some insurance companies and local agents require an alarm system to be installed into code or certified by an independent third party. The alarm system is required to have maintenance checks done every 6 - 12 months (in the UK, Audible Only 'intruder alarm' systems require routine service visits every 12 months and monitored intruding alarm systems require double checking in every 12-year period) to ensure all internal components, sensors and PSUs function properly. In the past, this would require an alarm service engineer to attend the site and bring an exit check. With the use of an Internet or radio line and a compatible IP/radio transmitter (at a location of concern), some checks can now be done remotely from a central station.
See also
- Access control
- Alarm management
- Security door
- Double loop
- Emergency services
- Environmental design
- Fire alarm
- Break-break detector
- Physical security
- Security lighting
- Destroyer button
References
Source
- Trimmer, H. William (1981). Understanding and Fixing Alarm Systems . Stoneham: Butterworth.
- Weber, Thad L. (1985). Alarm Systems and Burglary Protection (2d ed.). Stoneham, MA: Butterworth.
- Walker, Philip (1985). Electronic Security System. Cambridge, UK: Press University
- Ramsey, Anthony Home Security.
- Schatz, David A., et al. Video security curtain . US Pat. 6,297,844, Published October 2, 2001.
- Atss, R. Nandakumar.
- Aii, N. Clifton. "Broadband CSV, XML Data Alarm Standard" Auckland NZ, (2002)
- "Chinese wolf guard alarm system" CN, (1998)
External links
- How the burglar alarm works
Source of the article : Wikipedia
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