The first stage of classification of alarm systems is by purpose. The most famous:

• security;
• fire department;
• automotive.

Security fire alarm (FS) is designed to detect factors that can lead to property damage or threaten the life and health of people.

Modern security systems are mostly automatic. They do not require human intervention to operate. You can even automate the process of taking and withdrawing. For this purpose, there is, although not everywhere, the option of arming an object on a schedule.

To be fair, it must be said that it is rarely used. Firstly, there are practically no enterprises that start and finish work exactly at the same time. Secondly, it is more convenient (more reliable) for the owner to visually check the condition of the alarm system and make sure there are no malfunctions.

Naturally, people react to sensors. But even here, the “smart system” is capable of independently taking certain actions. These include: automatic activation of fire extinguishing, smoke removal, warning and evacuation control in case of fire.

Automatic security and fire alarm systems are provided with uninterruptible power supply. If there is no voltage in the electrical network, it must operate in standby mode for at least 24 hours.

Types of security alarms.

Depending on the method of responding to an alarm, a security alarm can be:

• with output to the centralized security console (CSC);
• autonomous.

It is customary to classify GSM signaling as a separate category, but this is not always correct. The state of the fire alarm system can be monitored by both the central monitoring station operator and the owner of the protected facility using the GSM module. In the latter case, it will be considered autonomous, even if the owner independently responds to alarm notifications.

True, the above classification was formed when there was no cellular communication, therefore, taking into account today's realities, it makes sense to distinguish three types of security: autonomous, with output to the security console or mobile phone owner.

Regardless of the notification method, security systems can be wireless or wired by type of information transmission. In this case, these methods are used both for the object part and for remote communication with the console.

Types of alarm sensors.

Sensors (detectors) must be installed at the protected facility, which are used to detect attempts at entry or fires.

Obviously, sensors are divided into:

Types of fire alarms.

All fire protection systems are usually divided into three types:

• threshold;
• targeted survey;
• addressable analog.

The features and operating principle of each of them are described on this page. They are listed in order of increasing complexity, respectively options, including information content.

It is impossible to say which is better - it all depends on the category of the object. For a small office or store, a threshold fire system is quite suitable. For trade entertainment center installation of ADDRESS APS is required.

FIRE ALARM TECHNICAL EQUIPMENT

First of all, security funds are classified according to their purpose:

• sirens;
• Power supplies.

In addition, security systems can use readers, code keypads, and other control and management tools.

Wired and wireless technologies have already been discussed. It is worth mentioning the classification of detectors by purpose. For a security alarm, these will be detection sensors:

• movements (volume);
• breach building structures(vibrating);
• breaking of glazed surfaces (acoustic or sound);
• opening (magnetic contact).

For fire protection systems, detectors are produced that can respond to smoke (smoke), heat, and open flame.

Receiving control devices (RCDs) monitor the status of detectors and generate signals that determine their status. The main characteristics of the PCP are:

Information capacity– number of controlled loops, zones or sensors.

Information content– the number of generated notifications depending on the state of the loops. There should be at least two of them: “normal”, “alarm”. In practice, devices display information about the status of each loop. In addition to the above, notifications “armed”, “disarmed”, “fault”, etc. can be displayed.

Signal lights- these are lamps; LED modules; light indicators indicating the exit, direction of evacuation routes, etc. TO sound annunciators include sirens and loudspeakers.

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This market is expected to see double-digit growth rates, especially in addressable device installations and wireless systems.

The source of renewable income in the security industry, in fact, its "cash cow", is remote control security, as well as the technical means that are supplied to clients to provide it.

“We just fell in love with subscriber revenue,” says Wayne Beck, CEO of A-Com Protection Services Inc., in Columbus, Ga. “If we're going to stay in this business, we're going to have to face with the fact that renewable revenues can only be counted on if costs are fully controlled. We had to change the paradigm. If this had not happened, we would not have been able to stay in business. Believe it or not, we now make money from protecting the residential sector."

Beck has expanded the hardware composition offered to customers security system, while raising the price of the basic user kit to $400 and reducing the price of a monthly monitoring subscription by $10. At the same time, the reduction in the actual price was 2 dollars, and the remaining 8 were freed up due to the abolition of the monthly system maintenance fee. This strategy contributed to 20% growth in his business.

“We felt that it was necessary to demonstrate to the client that if he purchases systems from our competitors, then with lower one-time costs he will pay a higher subscription fee, but with us - on the contrary; over a long period of time, his total monitoring costs will be significantly below -- and we've made that our marketing philosophy," Beck explains.

Ronald Petrarca, Director of Operations, Licensing and Compliance Administrator, Electronix Systems C.S.A. Inc. from Huntington Station, NY New York believes that the remote security industry has “punished” itself with a price crisis. “Competition has had a negative impact on this business, as the increase in the supply of “simplified” and free-to-install systems has led to the fact that a certain part of customers have become quite happy with low-budget security systems,” he says.

Thomas Patterson, Chairman and CEO of Kimberlite Corporation of Fresno, NY. California, reported that its sales were successful. “In the last three years, we’ve been going all out, raising sales by a quarter in a year,” he says. “Today, a certain share of this growth comes from video surveillance systems, which are currently at the peak of popularity; however, the same is true with sales of security systems things are going well."

"If the trend towards a stronger CCTV sector continues, it could have a negative impact on our profits as competition in this market segment is too intense - it's difficult to compete with the Internet," he admits.

Patterson is optimistic about the fire alarm business's prospects. “For companies that have taken the time to assemble a team of professionals, the opportunity for work in the fire alarm field is enormous,” he says. “The commercial market is still a busy construction market, and the old generation players are still in some confusion, and this is beneficial for people like us."

“Over the past few years, we have created a separate division that works in the fire safety profile, and have brought together fire professionals in it - and therefore we have found ourselves in a very convenient position to do business in this area as well,” emphasizes Patterson.

John Doyle Jr., CEO of Doyle Security Systems Inc. from Rochester, NY New York City reports a 15% increase in sales of security alarm systems over the past year. He talks about clients who travel frequently and are therefore away from their place of residence, as well as those who own a second home or apartment that is sometimes empty.

Drew Chernoy, responsible for finance and business development at Scarsdale Security Systems Inc. from Scarsdale, PC. New York, concludes that customers' need to inquire about the condition of their homes while they are away has helped his company's business grow. But he also acknowledges the fact that he doesn’t come across clients looking for the cheapest possible solution very often.

“If a client wants to install a system for free, then he will find those who will be able to do it,” says Cherney. “The main support of our business is local clients to whom we were recommended by similar clients who are satisfied with our work. Similar customers know their money is well spent and appreciate our thoughtful service and support."

The company's efforts to promote its services in the market were also facilitated by the company's participation in the reality show "To Catch a Thief" on the Discovery Channel. “It looks like this little ‘exposure’ has had its results,” says Chernoy.

Wayne Warsager, president of New York Merchants Protective Co. Inc. from Freeport, PC. New York, reports a 30% increase in sales of fire alarm systems for his company. He explains this by the fact that municipalities have become more stringent in monitoring the implementation of norms, which until then remained only written down on paper - and therefore a tangible scope of work has appeared.

“The systems in demand today are somewhat broader in their range of capabilities than in previous years,” explains Warsager. “Municipalities today are delving deeper into what properties new objects should have, and are demanding them to an ever greater extent.”

Manufacturers show optimism

Those involved in the sales and distribution of fire alarm systems and security monitoring are generally optimistic in their forecasts for 2007.

“The commercial and residential fire alarm markets will continue to grow strongly,” says Richard Roberts, senior product manager for the security division of System Sensor in St. Charles, Ill. “This is driven by legislation, regulations and compliance standards.” fire safety".

Innovation also contributes to the growth of his company's business, which supplies alarm devices and peripherals worldwide. "We are constantly introducing new products to the market and improving existing models, says Roberts. “This is a real source of strength for our company.”

Roberts predicts a fairly high sales growth rate of close to 10% for the fire alarm products market in 2007. “This trend has been observed over the last two to three years,” he says.

Among those who also have an optimistic forecast for market development in 2007 is Rick Falbo, domestic sales manager at Summit System Technologies Inc. from Toronto. "We still feel, based on our internal forecasts, that 2007 will be a good year," Falbo says. "We believe the construction and remodeling markets are on solid ground in most areas."

“The main reserve of potential in the country is concentrated here,” he emphasizes. “And in other areas, even if they do not shine with super-success, everything seems relatively strong. If we take into account the totality of these forecasts, the year seems to be very successful.”

Bill Jackson, President of Digital Monitoring Products Inc. (DMP) from Springfield, PC. Montana is reporting double-digit growth, particularly in wireless technology and high-quality networked addressable security consoles.

More reserved in his predictions is Jim Paulson, senior product manager for the security alarm group at GE Security in Bradenton, N.C. Florida.

“In general, the market is alive, but there is too much competition in it,” says Paulson. “It requires a lot of effort from each player because they are fighting for the same piece of the pie.”

"Manufacturers have not yet developed products that will expand the market or business propositions that would put us on a path to growth," says Paulson. "The key is to figure out how we will 'break through.'" GE Security is looking for ways to expand the pie for yourself and your clients, and that’s not easy.”

Operators of centralized security control stations report a significant increase in service volumes and expect further growth in 2007.

“We're finding that the best dealers, with more sound business plans and adequate funding, are growing volumes at a much faster rate than they have seen in the previous five years,” said Russell McDonnell, chairman of the board of directors of Syracuse, N.Y.-based Rapid Response. York: “From our point of view, this year is one of the best in these five years.”

Scott Sturges, director of product marketing for fire alarm systems at ADI, a distributor based in Melville, N.C. New York, speaks of record growth. “In 2006, ADI set a record for sales of security and fire protection products,” he says. “Our sales numbers have been growing very well over the last 24 months.”

However, as Sturges warns, the strong start seen in January this year is not necessarily an indicator of future success. “It’s difficult to predict what will happen next,” he admits. “The security and fire alarm market is seasonal. We usually see a strong jump in activity from April to September-October, and therefore we are looking forward to seeing if this will happen at all in this year."

He is equally cautious about the prospects for the security alarm market, although he is confident that fire alarm distribution will do well because commercial construction has maintained its position and budget spending in this category remains high.

"On the burglar alarm side, I'm a little less optimistic because the strength of the residential market has waned," he warns. "There are a number of signs in the market that could negatively impact the burglar alarm business in the US."

Competition

Beck believes that competition among security alarm companies has remained at the same level as in previous years. “We're seeing more and more companies wanting to get into this business,” he says. “I also own a telephone company, and we're sort of an integrator in that area. And if I have competition from resellers here, This is almost never seen in the security alarm industry.”

Petrarca agrees that there is often competition from companies outside the security industry. “It’s not just manufacturers of network and telephone equipment who have started making alarms, but also manufacturers of audio equipment,” he complains. “Oil workers have been doing this for a number of years.”

Doyle faces the challenge of finding qualified contractors for his contracts. “In many cases, their shortage increases either the costs or the completion time,” he notes.

Beck is also trying to improve his customer service. “We strive to provide the customer with the services that he wants, and not those that we assume he wants,” says Beck. “Many people think that they provide good service, but in reality they have such problems with it..."

“I’ve been in this business for 34 years, and I still sometimes get calls from clients with complaints,” he admits. “That’s why I give my contact details in directories. If the client is not satisfied with our services and is irritated by this, then it’s better "Let me know. If you talk to him about it first, you will be responsible for making sure the client is taken care of properly."

One of Patterson's concerns is staffing his company's central control room. “Our central security station in Fresno, California, helped local police catch 552 burglars red-handed during 2006 while attempting to burglarize or damage our clients' protected property,” he states. “In 2005, 576 people were caught.” After all, we only have 6,900 security systems in service.”

“We can’t get enough of our central station, seeing it as the main key to our success,” proclaims Patterson. “Because, you know, we have to constantly hire employees, train them and improve the skills of the station staff - to improve communication with customers "To a new level of quality. It's never easy, and we're just blessed to have a top-notch team and brilliant management at our station."

Which products are profitable?

Roberts cites stringent legal requirements for the installation of fire alarm systems and carbon monoxide detection systems in residential and industrial buildings as one of the reasons why his company sees growth prospects.

"We're all seeing this market grow," he says of carbon monoxide detectors. IN last years The legislation obliging their use is constantly being tightened. He also notes addressable and wireless smoke detectors are among the products seeing increased sales.

“It is expected that their sales growth rate could approach 20%, while sales of conventional wired smoke detectors will remain approximately the same,” he says. “This is primarily due to the fact that addressable and wireless smoke detectors provide a broader range of capabilities than wired detector systems."

The company Falbo works for, Summit System Technologies, was formed in January 2006 by its parent company, Mircom Technologies Ltd. from Vaughan (Ontario, Canada). This was a reaction to the growth in sales of addressable fire alarm panels it noted.

“We are observing the following trend: installers prefer to lay new lines for addressable alarm devices instead of existing wiring. And addressable systems are installed not only at large, but also at small objects, as well as in reconstructed buildings,” Falbo emphasizes. Legislative requirements are becoming more and more stringent, which in practice gives the green light to the introduction of addressable systems, since they are more user-friendly, especially in emergency situations.”

Paulson is also enthusiastic. “Our fire systems business is growing at double-digit percentages, triple the overall market, thanks to our channel partners and product platform capabilities,” he says. “In addition, our sales growth rate Our security systems are approaching the 10% mark."

"Our fire alarm channel has grown a little faster than our security dealer channel, so I would say the integration channel engineering systems growth has slightly exceeded the 10% mark, while the security dealer channel is not reaching that threshold,” continues Paulson.

Profitability indicators for Paulson's company are also not bad, but he himself continues to consider this a problem area. "We must continue to invest in new product development and look for opportunities to formulate unique service offerings that have no precedent in today's market - and we are already working on some of this," he says.

He is also concerned about the problems that some dealers and integrators are facing. “Some can't grow because they can't find enough installers,” says Paulson. “We need to find new ways to save labor so our dealers can use the same talent pool to install more equipment—for example, more actively implement wireless systems."

New products from Amityville, Napco Security Group. New York, are designed to simplify the installation process. “Sales of older corded systems appear to be in decline and are being replaced by newer, easier-to-install hybrid systems that require less skilled labor to install,” said Judy Jones, group vice president of marketing. Our dealers' needs to limit labor costs led us to make this change, and we responded by adapting to their changing labor patterns."

Industry problems

Jackson pinpoints growth opportunities to several vertical markets. “Our product continues to be attractive to financial institutions because it gives them the ability to operate in a networked environment that they are familiar with,” he says. “The retail segment also remains very promising and our sales performance there is growing year on year.” Federal Government provides a ton of options and we have remotes specifically designed to meet government requirements."

Among the trends noted by Rod Garner, president of Ogden, N.C.-based Mountain Alarm. Utah also includes the development of wireless communication technologies.

“The success of summer marketing programs has changed the way investment capital views the industry,” he says. “The whole story of this relationship model can be told by asset depreciation numbers and sustained positive results. As a representative of the old school, I believe that the new model will "will be seriously bitten by wear and tear, but the smart money will find quality operators to ensure a good balance between growth rates and things like asset wear and tear."

Sales of new equipment by Electronix Systems continue, as Petrarca says, to compete with obsolete but surviving systems. He sees the problem as Internet telephony continues to evolve.

"Fewer and fewer customers are installing landline phone lines," he points out, adding that as analog cellular monitoring services are moving away from the market, "radio and Internet-based systems have started to sell well."

Warsager is already preparing to deal with the problems caused by the decommissioning of analog AMPS cellular networks, as well as the spread of Internet telephony.

“It basically interferes with the signal transmission process,” says Warsager about Internet telephony. “No matter what we do to inform users, things don’t always happen as we plan. They start using Internet channels -telephony without us being aware of it. The fact is that reconfiguring the system to take into account the use of VoIP services takes a little more time than a regular call to the help desk - and therefore this has a certain impact on our company."

Melissa Brankman, director of customer service for Custom Alarm in Rochester, N.C. Minnesota is seeing a significant increase in the number of homeowners switching from traditional landlines to using the Internet or cable connections, but it also sees a downside.

“There is a strong desire to fully automate the home environment and implement all-in-one solutions—especially in new homes,” she notes. “But for a security system, this is not always the best option. Often, the homeowner is enamored with the opportunity to have everything services in one hand, forgets about the saying that does not recommend “putting all your eggs in one basket.”

Future

New products create new markets for Doyle. "Customers are also interested in our ability to keep their homes safe with water leak detectors, carbon monoxide monitors and temperature sensors," he says.

Beck is optimistic about the industry's prospects. “I think that everything is in order with the future,” he says. “We just have to make sure that our professionalism is maintained and even enhanced and that we keep the client’s interests in sight. Otherwise, we often go to great lengths.” our own thoughts about what exactly we should sell, not noticing that customers may want to buy something completely different."

The need for emergency calls is expected to increase

The possibility of increased demand for monitoring services is an optimistic note noted by Scott Sturges, director of product marketing for fire and intrusion alarm products at Melville, N.C.-based ADI. New York, is to develop personal emergency response systems (PERS). “I think one of the technologies that is somewhat ahead of its time that we are trying to bring to market today is personal emergency response systems (PERS), admits Sturges. “We see significant potential for business growth in them.” for the next few years." “Many of our dealers sell PERS systems because installation is quick, the systems are wireless, and the subscription fees are higher than standard security and anti-burglary systems,” he says. “So even if dealers only process existing "They have a customer base and can realistically distribute PERS products for use in geriatric care. With America's population aging, this is a good opportunity for our dealers to enter the Personal Emergency Call System sector." Wayne Warsager, president of New York Merchants Protective Co. Inc. from Freeport, PC. New York, agrees that PERS systems are important. "Lonely seniors and social service workers will want to be able to stay in their homes, and monitoring PERS systems will become a very significant business," he says. Sturges also notes a "tremendous increase" in the use of cellular digital GSM radio systems as backup, as analogue systems are due to be phased out in February 2008.

One of the most important security elements is burglar and fire alarms. These two systems have a lot in common - communication channels, similar algorithms for receiving and processing information, sending alarm signals, etc. Therefore, they are often (for economic reasons) combined into a single security and fire alarm (OPS). Security and fire alarms are among the oldest technical means of security. And until now this system is one of the most effective security systems.

Modern protection systems are built on several alarm subsystems (the combination of their use makes it possible to monitor any threats):

security – detects an attempt to penetrate;

alarm - an emergency call system for help in case of a sudden attack;

fire department – ​​registers the appearance of the first signs of fire;

emergency - notifies about gas leaks, water leaks, etc.

The task fire alarm are the receipt, processing, transmission and presentation in a given form to consumers using technical means of information about a fire at protected facilities (detecting a fire, determining the location of its occurrence, sending signals for automatic fire extinguishing and smoke removal systems). Task burglar alarm– timely notification of penetration or attempted penetration of a protected facility, with recording of the fact, place and time of violation of the security line. The common goal of both alarm systems is to provide an immediate response, providing accurate information about the nature of the event.

An analysis of domestic and foreign statistics on unauthorized intrusions into various facilities shows that more than 50% of intrusions are committed on facilities with free access for personnel and clients; about 25% - for objects with unguarded mechanical protection elements such as fences, gratings; about 20% - for objects with a pass-through system and only 5% - for objects with an enhanced security regime, using complex technical systems and specially trained personnel. From the practice of security services when protecting objects, six main zones of protected areas are distinguished:

zone I – the perimeter of the territory in front of the building;

zone II – the perimeter of the building itself;

zone III – premises for receiving visitors;

zone IV – employee offices and corridors;

zones V and VI – management offices, negotiation rooms with partners, storage of valuables and information.

In order to ensure the required level of reliability of the protection of particularly important objects (banks, cash desks, weapons storage areas), it is necessary to organize multi-faceted protection of the object. First line alarm sensors are installed on the outer perimeter. The second line is represented by sensors installed in places of possible penetration into an object (doors, windows, vents, etc.). The third line is volumetric sensors in interior spaces, the fourth is directly protected objects (safes, cabinets, drawers, etc.). In this case, each line must be connected to an independent cell of the control panel so that if an intruder possibly bypasses one of the security lines, an alarm signal is given from the other.

Modern security systems are often integrated with other security systems into single complexes.

2.2. Structure of security and fire alarm systems

In general, the fire alarm system includes:

sensors– alarm detectors that respond to an alarming event (fire, attempt to enter an object, etc.), the characteristics of the sensors determine the main parameters of the entire alarm system;

control panels(PKP) - devices that receive an alarm signal from detectors and control actuators according to a given algorithm (in the simplest case, monitoring the operation of a fire alarm system consists of turning sensors on and off, recording alarm signals, in complex, branched alarm systems, monitoring and control is carried out using computers);

actuators– units that ensure the execution of a given algorithm of system actions in response to a particular alarm event (sending an alert signal, turning on fire extinguishing mechanisms, auto-dialing specified phone numbers, etc.).

Typically, security and fire alarm systems are created in two versions - fire alarm system with local or closed security of the facility or fire alarm system with transfer of protection to private security units (or a private security company) and the fire service of the Russian Ministry of Emergency Situations.

The whole variety of security and fire alarm systems, with some degree of convention, is divided into addressable, analog and combined systems.

1. Analogue (non-addressable) systems are built according to the following principle. The protected object is divided into areas by laying separate loops that combine a number of sensors (detectors). When any sensor is triggered, an alarm is generated throughout the entire loop. The decision about the occurrence of an event is “made” only by the detector, the functionality of which can only be checked during maintenance of the alarm system. Also, the disadvantages of such systems are the high probability of false alarms, signal localization accurate to the loop, and limitation of the controlled area. The cost of such a system is relatively low, although it is necessary to lay a large number of loops. The tasks of centralized control are performed by the security and fire panel. The use of analogue systems is possible at all types of objects. But with a large number of alarm areas, there is a need for a large amount of work on the installation of wired communications.

2. Address systems assume installation of addressable sensors on one alarm loop. Such systems make it possible to replace multi-core cables connecting detectors with a control panel (PKP) with one pair of data bus wires.

3. Addressable non-survey systems are, in fact, threshold ones, supplemented only by the ability to transmit the address code of the triggered detector. These systems have all the disadvantages of analog systems - the inability to automatic control operability of fire detectors (in case of any electronic failure, communication between the detector and the control panel is terminated).

4. Addressed survey systems carry out periodic polling of detectors, ensure monitoring of their performance in case of any type of failure, which makes it possible to install one detector in each room instead of two. In targeted surveys, OPS can be implemented complex algorithms information processing, for example, automatic compensation for changes in detector sensitivity over time. The likelihood of false positives is reduced. For example, an addressable glass break sensor, unlike a non-addressable one, will indicate which window was broken. The decision about the event that occurred is also “made” by the detector.

5. The most promising direction in the field of building alarm systems is combined (addressable-analog) systems. Address- analog detectors they measure the amount of smoke or temperature at the facility, and the signal is generated based on mathematical processing of the received data in the control panel (specialized computer). It is possible to connect any sensors; the system is able to determine their type and the required algorithm for working with them, even if all these devices are included in one security alarm loop. These systems provide maximum speed decision making and management. For the correct operation of analog addressable equipment, it is necessary to take into account the communication language of its components (protocol), unique for each system. The use of these systems makes it possible to quickly, without high costs, make changes to already existing system when changing and expanding the zones of the object. The cost of such systems is higher than the previous two.

Now there is a huge variety of detectors, control panels and sirens with different characteristics and capabilities. It should be recognized that the defining elements of security and fire alarm systems are sensors. The parameters of the sensors determine the main characteristics of the entire alarm system. In any of the detectors, the processing of controlled alarm factors is, to one degree or another, an analog process, and the division of detectors into threshold and analog relates to the method of transmitting information from them.

Based on the location of installation at the site, sensors can be divided into internal And external, installed respectively inside and outside protected objects. They have the same principle of operation, the differences lie in design and technological characteristics. The installation location may be the most important factor influencing the choice of detector type.

Fire alarm detectors (sensors) operate on the principle of recording environmental changes. These are devices designed to determine the presence of a threat to the security of a protected object and transmit an alarm message for a timely response. Conventionally, they can be divided into volumetric (allowing control of space), linear, or surface, for monitoring the perimeters of territories and buildings, local, or point, for monitoring individual objects.

Detectors can be classified according to the type of physical parameter being monitored, the principle of operation of the sensitive element, and the method of transmitting information to the central alarm control panel.

Based on the principle of generating an information signal about the penetration of an object or a fire, fire alarm detectors are divided into active(the alarm generates a signal in the protected area and reacts to changes in its parameters) and passive(react to changes in environmental parameters). Such types of security detectors as passive infrared, magnetic contact glass break detectors, perimeter active detectors, combined active detectors are widely used. Fire alarm systems use heat, smoke, light, ionization, combined and manual call points.

The type of alarm system sensors is determined physical principle actions. Depending on the type of sensors, security alarm systems can be capacitive, radio-beam, seismic, responsive to the closure or opening of an electrical circuit, etc.

The possibilities for installing security systems depending on the sensors used, their advantages and disadvantages are given in Table. 2.

table 2

Perimeter security systems

2.3. Types of security detectors

Contact detectors serve to detect unauthorized opening of doors, windows, gates, etc. Magnetic detectors consist of a magnetically controlled reed sensor installed on the stationary part, and a setting element (magnet) installed on the opening module. When the magnet is near the reed switch, its contacts are in a closed state. These detectors differ from each other in the type of installation and the material from which they are made. The disadvantage is that they can be neutralized by a powerful external magnet. Reed shielded sensors are protected from extraneous magnetic fields by special plates and are equipped with signal reed contacts that are triggered in the presence of an extraneous field and warn about it. When installing magnetic contacts in metal doors It is very important to shield the field of the main magnet from the induced field of the entire door.

Electrical contact devices– sensors that sharply change the voltage in the circuit under a certain influence on them. They can be either clearly “open” (current flows through them) or “closed” (no current flows). The simplest way to build such an alarm is to thin wires or strips of foil, connected to a door or window. Wire, foil or conductive compound “Paste” is connected to the alarm through door hinges, closures, and also through special contact blocks. When attempting to penetrate, they are easily destroyed and create an alarm signal. Electrical contact devices provide reliable protection from false alarms.

IN mechanical door contact devices the moving contact protrudes from the sensor body and closes the circuit when pressed (closing the door). The installation location of such mechanical devices is difficult to hide, and they can be easily damaged by securing the lever in a closed position (for example, with chewing gum).

Contact mats are made from two decorated sheets of metal foil and a layer of foam plastic between them. The foil bends under the weight of the body, and this provides an electrical contact that generates an alarm signal. Contact mats operate on a normally open principle and a signal is given when the electrical contact device completes a circuit. Therefore, if you cut the wire leading to the mat, the alarm will not work in the future. A flat cable is used to connect the mats.

Passive Infrared Detectors (PIR) serve to detect an intruder's intrusion into a controlled volume. This is one of the most common types of security detectors. The principle of operation is based on recording changes in the flow of thermal radiation and converting infrared radiation into an electrical signal using a pyroelectric element. Currently, two- and four-area pyroelements are used. This allows you to significantly reduce the likelihood of false alarms. In simple PIR signal processing is carried out using analogue methods, in more complex ones – digitally, using a built-in processor. The detection zone is formed by a Fresnel lens or mirrors. There are volumetric, linear and surface detection zones. It is not recommended to install infrared detectors in close proximity to ventilation openings, windows and doors that create convection air currents, as well as heating radiators and sources of thermal interference. It is also undesirable for direct light from incandescent lamps, car headlights, or the sun to enter the detector entrance window. It is possible to use a thermal compensation circuit to ensure operability in the area high temperatures(33–37 °C), when the signal from human movement sharply decreases due to a decrease in the thermal contrast between the human body and the background.

Active detectors They are an optical system consisting of an LED that emits infrared radiation in the direction of the receiver lens. The beam of light is modulated in brightness and operates at a distance of up to 125 m and allows you to form a security line invisible to the eye. These emitters come in both single-beam and multi-beam types. When the number of beams is more than two, the possibility of false alarms is reduced, since the formation of an alarm signal occurs only when all beams intersect simultaneously. The configuration of zones can be different - “curtain” (intersection of a surface), “beam” (linear movement), “volume” (movement in space). Detectors may not work in rain or heavy fog.

Radio wave volumetric detectors serve to detect penetration of a protected object by registering the Doppler frequency shift of the reflected ultra-high frequency (microwave) signal that occurs when the attacker moves in the electromagnetic field created by the microwave module. It is possible to install them covertly on site behind materials that transmit radio waves (fabrics, wood boards and so on.). Linear radio wave detectors consist of a transmitting and receiving unit. They generate an alarm when a person crosses their coverage area. The transmitting unit emits electromagnetic oscillations, the receiving unit receives these oscillations, analyzes the amplitude and time characteristics of the received signal, and if they correspond to the “intruder” model embedded in the processing algorithm, generates an alarm notification.

Microwave sensors have lost their former popularity, although they are still in demand. In relatively new developments, a significant reduction in their dimensions and energy consumption has been achieved.

Volumetric ultrasonic detectors serve to detect movement in the protected area. Ultrasonic sensors are designed to protect premises by volume and give an alarm both when an intruder appears and when a fire occurs. The detector's radiating element is a piezoelectric ultrasonic transducer that produces acoustic vibrations of air in a protected volume under the influence of electrical voltage. The detector's sensitive element, located in the receiver, is a piezoelectric ultrasonic receiving converter of acoustic vibrations into an alternating electrical signal. The signal from the receiver is processed in the control circuit, depending on the algorithm embedded in it, and generates one or another notification.

Acoustic detectors are equipped with a highly sensitive miniature microphone that picks up the sound produced when sheet glass breaks. The sensitive element of such detectors is a condenser electret microphone with a built-in field-effect transistor pre-amplifier. When glass breaks, two types of sound vibrations occur in a strictly defined sequence: first, a shock wave from the vibration of the entire glass mass with a frequency of about 100 Hz, and then a wave of glass destruction with a frequency of about 5 kHz. The microphone converts sound vibrations in the air into electrical signals. The detector processes these signals and makes a decision about the presence of intrusion. When installing the detector, all areas of the protected glass must be within its direct visibility.

Capacitive system sensor represents one or more metal electrodes placed on the structure of the protected opening. The principle of operation of capacitive security detectors is based on recording the value, speed and duration of change in the capacitance of the sensitive element, which is used as metal objects connected to the detector or specially laid wires. The detector generates an alarm when the electrical capacitance of a security item (safe, metal cabinet) changes relative to the “ground” caused by a person approaching this item. Can be used to protect the perimeter of a building through tensioned wires.

Vibration detectors serve to protect against penetration of a protected object by destroying various building structures, as well as protecting safes, ATMs, etc. The operating principle of vibration sensors is based on the piezoelectric effect (piezoelectrics generate an electric current when the crystal is pressed or released), which consists of changing the electrical signal when the piezoelectric element vibrates. An electrical signal proportional to the vibration level is amplified and processed by the detector circuit using a special algorithm to separate the destructive effect from the interference signal. The operating principle of vibration systems with sensor cables is based on the triboelectric effect. When such a cable is deformed, electrification occurs in the dielectric located between the central conductor and the conductive braid, which is recorded as a potential difference between the cable conductors. The sensitive element is a sensor cable that converts mechanical vibrations into an electrical signal. There are more advanced electromagnetic microphone cables.

A relatively new principle of protecting premises is to use changes in air pressure when opening enclosed space (barometric sensors) has still not lived up to the expectations placed on it and is almost never used when equipping multifunctional and large facilities. These sensors have a high false alarm rate and quite strict application restrictions.

It is necessary to dwell separately on distributed fiber optic systems for perimeter security. Modern fiber optic sensors can measure pressure, temperature, distance, position in space, acceleration, vibration, sound wave mass, liquid level, strain, refractive index, electric field, electric current, magnetic field, gas concentration, radiation dose and etc. An optical fiber is both a communication line and a sensitive element. Laser light with a high output power and a short radiation pulse is supplied to the optical fiber, then the parameters of Rayleigh backscattering, as well as Fresnel reflection from the joints and ends of the fiber, are measured. Under the influence of various factors (deformation, acoustic vibrations, temperature, and with appropriate fiber coating - electric or magnetic field), the phase difference between the applied and reflected light pulse changes. The location of the inhomogeneity is determined by the time delay between the moment of radiation of the pulse and the moment of arrival of the backscattering signal, and the losses on the line section are determined by the intensity of the backscattering radiation.

To separate signals generated by an intruder from noise and interference, a signal analyzer based on the principle of a neural network is used. The signal to the input of the neural network analyzer is supplied in the form of a spectral vector generated by the DSP processor (Digital Signal Processing), the operating principle of which is based on fast Fourier transform algorithms.

The advantages of distributed fiber-optic systems are the ability to determine the location of a violation of the boundary of an object, use these systems to protect perimeters up to 100 km long, a low level of false alarms and a relatively low price per linear meter.

The leader among security alarm equipment currently is combined sensor, built on the simultaneous use of two human detection channels - IR-passive and microwave. Currently, it is replacing all other devices, and many alarm installers use it as the only sensor for volumetric protection of premises. The average time between false alarms is 3–5 thousand hours, and in some conditions reaches a year. It allows you to block rooms where passive IR or microwave sensors are not applicable at all (the former - in rooms with drafts and thermal interference, the latter - with thin non-metallic walls). But the detection probability of such sensors is always less than that of any of its two constituent channels. The same success can be achieved by using separately both sensors (IR and microwave) in the same room, and generating an alarm signal only when both detectors are triggered within a given time interval (usually a few seconds), using the capabilities of the control panel for this purpose.

2.4. Types of fire detectors

The following basic activation principles can be used to detect fire fire detectors:

smoke detectors - based on ionization or photoelectric principle;

heat detectors - based on recording the level of temperature rise or some specific indicator;

flame detectors - based on the use of ultraviolet or infrared radiation;

gas detectors.

Manual call points necessary to force the system into fire alarm mode by a person. They can be implemented in the form of levers or buttons covered with transparent materials (easily broken in a fire). Most often they are installed in easily accessible public areas.

Heat detectors react to changes in ambient temperature. Some materials burn with virtually no smoke emission (for example, wood), or the spread of smoke is difficult due to the small space (behind suspended ceilings). They are used in cases where there is a high concentration of aerosol particles in the air that have nothing to do with combustion processes (water vapor, flour in a mill, etc.). Thermal threshold fire detectors emit a “fire” signal when the threshold temperature is reached, differential– a fire hazard situation is recorded by the rate of temperature increase.

Contact threshold heat detector issues an alarm when a predetermined limit is exceeded permissible temperature. When heated, the contact plate melts, the electrical circuit is broken and an alarm signal is generated. These are the simplest detectors. Typically the threshold temperature is 75 °C.

A semiconductor element can also be used as a sensitive element. As the temperature rises, the resistance of the circuit drops and more current flows through it. When the threshold value of the electric current is exceeded, an alarm signal is generated. Semiconductor sensing elements have more high speed response, the threshold temperature can be set arbitrarily, and when the sensor is triggered, the device is not destroyed.

Differential heat detectors usually consist of two thermoelements, one of which is located inside the detector housing, and the second is placed outside. The currents flowing through these two circuits are fed to the inputs of the differential amplifier. As the temperature increases, the current flowing through the external circuit changes sharply. In the internal circuit it hardly changes, which leads to an imbalance of currents and the formation of an alarm signal. Using a thermocouple eliminates the influence of smooth temperature changes caused by natural causes. These sensors are the fastest in terms of response speed and stable in operation.

Linear heat detectors. The design consists of four copper conductors with shells made of a special material with a negative temperature coefficient. The conductors are packaged in a common casing so that their shells are in close contact. The wires are connected at the end of the line in pairs, forming two loops with the shells touching. Operating principle: as the temperature increases, the shells change their resistance, also changing the total resistance between the loops, which is measured by a special results processing unit. Based on the magnitude of this resistance, a decision is made about the presence of a fire. The longer the cable length (up to 1.5 km), the higher the sensitivity of the device.

Smoke detectors are designed to detect the presence of a given concentration of smoke particles in the air. The composition of smoke particles may vary. Therefore, according to the principle of operation, smoke detectors are divided into two main types - optoelectronic and ionization.

Ionization smoke detector. A stream of radioactive particles (usually americium-241 is used) enters two separate chambers. When smoke particles (the color of the smoke is not important) enter the measuring (external) chamber, the current flowing through it decreases, since this results in a decrease in the path length of the α-particles and an increase in the recombination of ions. For processing, the difference between the currents in the measuring and control chambers is used. Ionization detectors do not harm human health (source radioactive radiation about 0.9 µCi). These sensors provide real fire protection in explosive areas. They also have record low current consumption. The disadvantages are the difficulty of disposal after the end of its service life (at least 5 years) and vulnerability to changes in humidity, pressure, temperature, and air speed.

Optical smoke detector. The measuring chamber of this device contains an optoelectronic pair. An LED or laser (aspiration sensor) is used as a driving element. The radiation of the infrared spectrum master element under normal conditions does not reach the photodetector. When smoke particles enter the optical chamber, radiation from the LED is scattered. Due to the optical effect of infrared radiation scattering on smoke particles, light enters the photodetector, providing an electrical signal. The greater the concentration of scattering smoke particles in the air, the higher the signal level. For the correct operation of an optical detector, the design of the optical camera is very important.

Comparative characteristics of ionization and optical types of detectors are given in table. 3.

Table 3

Comparison of the effectiveness of smoke detection methods

Laser detector provides smoke detection at specific optical density levels approximately 100 times lower than modern LED sensors. There are more expensive systems with forced air suction. To maintain sensitivity and prevent false alarms, both types of detectors (ionization or photoelectric) require periodic cleaning.

Linear smoke detectors indispensable in rooms with high ceilings and large areas. They are widely used in fire alarm systems, as it becomes possible to detect a fire situation at very early stages. The ease of installation, configuration and operation of modern linear sensors allows them to compete in price with point detectors even in medium-sized rooms.

Combination smoke detector(ionization and optical types of detectors are collected in one housing) operates at two angles of light reflection, which allows you to measure and analyze the ratio of the characteristics of forward and back scattering of light, determining types of smoke and reducing the number of false alarms. This is achieved through the use of dual angle light scattering technology. It is known that the ratio of forward scattered light to backward scattered light for dark smoke (soot) is greater than for light types of smoke (smoldering wood), and even higher for dry substances (cement dust).

It should be noted that the most effective detector is one that combines photoelectric and thermal sensitive elements. Today they are produced and three-dimensional combination detectors, they combine smoke optical, smoke ionization and thermal detection principles. In practice they are used quite rarely.

Flame detectors. An open fire has characteristic radiation in both the ultraviolet and infrared parts of the spectrum. Accordingly, two types of devices are produced:

ultraviolet– a high-voltage gas-discharge indicator constantly monitors the radiation power in the ultraviolet range. When an open fire appears, the intensity of the discharges between the indicator electrodes increases greatly and an alarm signal is issued. Such a sensor can monitor an area of ​​up to 200 m 2 at an installation height of up to 20 m. Response delay does not exceed 5 s;

infrared– using an IR sensitive element and an optical focusing system, characteristic bursts of IR radiation are recorded when a fire occurs. This device allows you to determine within 3 s the presence of a flame with a size of 10 cm at a distance of up to 20 m at a viewing angle of 90°.

Now a new class of sensors has appeared - analogue detectors with external addressing. The sensors are analog, but are addressed by the alarm loop in which they are installed. The sensor performs self-testing of all its components, checks the dust content of the smoke chamber, and transmits the test results to the control panel. Compensation for dust in the smoke chamber allows you to increase the operating time of the detector before the next maintenance; self-testing eliminates false alarms. Such detectors retain all the advantages of addressable analog detectors, have a low cost and are able to work with inexpensive non-addressable control panels. When installing several detectors in an alarm loop, each of which will be installed alone in the room, it is necessary to install remote optical indication devices in the common corridor.

The criterion for the effectiveness of OPS equipment is to minimize the number of errors and false positives. The presence of one false alarm from one zone per month is considered an excellent result of work. The frequency of false alarms is the main characteristic by which one can judge the noise immunity of a detector. Noise immunity– this is an indicator of the quality of the sensor, characterizing its ability to operate stably under various conditions.

The fire alarm system is controlled from a control panel (concentrator). The composition and characteristics of this equipment depend on the importance of the object, the complexity and ramifications of the alarm system. In the simplest case, monitoring the operation of an alarm system consists of turning sensors on and off and recording alarms. In complex, extensive alarm systems, monitoring and control are carried out using computers.

Modern security alarm systems are based on the use of microprocessor control panels connected to a surveillance station via wired lines or radio. The system can have several hundred security zones; to facilitate management, the zones are grouped into sections. This allows you to arm and disarm not only each sensor individually, but also a floor, building, etc. Typically, a section reflects some logical part of an object, for example, a room or group of rooms, united by some significant logical feature. Reception and control devices allow you to: control and monitor the state of both the entire alarm system and each sensor (on-off, alarm, failure, failure on the communication channel, attempts to open sensors or the communication channel); analysis of alarm signals from various types of sensors; checking the functionality of all system nodes; alarm recording; interaction of the alarm system with other technical means; integration with other security systems (security television, security lighting, fire extinguishing system, etc.). The characteristics of non-addressable, addressable and addressable analogue fire alarm systems are given in Table. 4.

Table 4

Characteristics of non-addressable, addressable and addressable analogue fire alarm systems

2.5. Processing and logging information, generating alarm control signals

To process and record information and generate control alarm signals, various control and control equipment can be used - central stations, control panels, control panels.

Reception and control device (PKP) supplies power to security and fire detectors via security and fire alarm loops, receives alarm notifications from sensors, generates alarm messages, and also transmits them to a centralized monitoring station and generates alarm signals for triggering of other systems. Such equipment is distinguished by its information capacity - the number of controlled alarm loops and the degree of development of control and warning functions.

To ensure compliance of the device with the chosen application tactics, fire and security alarm control panels are distinguished for small, medium and large objects.

Typically, small facilities are equipped with non-addressable systems that monitor several security and fire alarm loops, while medium and large facilities use addressable and addressable analogue systems.

PKP of low information capacity. Typically, these systems use security and fire alarm and control devices, where the maximum permissible number of sensors is included in one loop. These control panels allow you to solve a maximum of problems at relatively low costs for completing the system. Small control panels have loop versatility for their purpose, i.e. it is possible to transmit signal and control commands (alarm, security, fire operating modes). They have a sufficient number of outputs to the central monitoring console and allow you to record events. The output circuits of small control panels have outputs with sufficient current to power the detectors from the built-in power supply and can control firefighting or technological equipment.

Currently, there is a tendency to use instead of low information capacity control panels, medium information capacity control panels. With this replacement, one-time costs almost do not increase, but labor costs when eliminating faults in the linear part are significantly reduced due to the precise determination of the location of the failure.

PKP of medium and large information capacity. For centralized reception, processing and reproduction of information from large number Security facilities use remote control and centralized surveillance systems. When using a device with a common central processor with a concentrated or tree-like structure for laying out loops (both addressable and addressless fire alarm systems), incomplete use of the information capacity of the control panel leads to a slight increase in the cost of the system.

IN address systems one address must correspond to one addressable device (detector). When using a computer, due to the absence of a central control panel and limited monitoring and control functions in the control panel units themselves, difficulties arise in power backup and the impossibility of full functioning of the alarm system in the event of a failure of the computer itself.

IN addressable analog fire control panels the price of equipment per address (control panel and sensor) is twice as high as that of analog systems. But the number of addressable analog sensors in individual rooms, compared to threshold (maximum) detectors, can be reduced from two to one. Increased adaptability, information content, and self-diagnosis of the system minimize operating costs. The use of addressable, distributed or tree structures minimizes the cost of cables and their installation, as well as the cost of maintenance by up to 30–50%.

The use of control panels for fire alarm systems has some features. The system structures used are divided as follows:

1) control panel with a concentrated structure (in the form of a single block, with addressless radial loops) for fire alarm systems of medium and large information capacity. Such control panels are used less and less often; it can be recommended to use them in systems with up to 10–20 loops;

2) control panel of addressable analogue fire alarm systems. Addressable analog control and control devices are much more expensive than addressable threshold devices, but do not have any special advantages. They are easier to install, maintain and repair. They have significantly increased information content;

3) control panel of addressable fire alarm systems. Groups of threshold sensors form addressable control zones. The control panels are structurally and programmatically composed of complete functional blocks. The system is compatible with detectors of any design and operating principle, turning them into addressable ones. All devices in the system are usually addressed automatically. They allow you to combine most of the advantages of addressable analog systems with the low cost of maximum (threshold) sensors.

To date, a digital-to-analog alarm loop has been developed, combining the advantages of analog and digital loops. It has more information content (in addition to ordinary signals, additional signals can be transmitted). The ability to transmit additional signals allows you to avoid setting up and programming alarm loops and to use several types of detectors in one loop while automatically configuring to work with any of them. This reduces the required number of alarm loops for each object. In this case, the control panel can simulate the operation of an alarm loop at the command of its detector to transmit information to another similar device that plays the role of central monitoring console (Monitoring station).

The monitoring station can not only receive information, but also transmit basic commands. This fire and security device does not require special programming (configuration occurs automatically, similar to the “Plug & Play” function in a computer). Therefore, highly qualified specialists are not required for maintenance. In one fire loop, the device receives signals from heat, smoke, manual call points, engineering system control sensors, distinguishes between the activation of one or two detectors, and can even work with analog fire detectors. The address of the alarm loop becomes the address of the room, without programming the parameters of the device or detectors.

2.6. OPS actuators

Actuators OPS must ensure the implementation of the specified system response to an alarm event. The use of intelligent systems makes it possible to carry out a set of measures related to fire extinguishing (fire detection, alerting special services, informing and evacuating personnel, activating the fire extinguishing system), and carry them out in a fully automatic mode. Automatic fire extinguishing systems have long been used, releasing a fire suppressant into a protected area. They can contain and extinguish fires before they become actual fires and act directly on the source of the fire. Now there are a number of systems that can be used without damage to equipment (including those with electronic filling).

It should be noted that connecting automatic fire extinguishing systems to fire alarm control panels is somewhat ineffective. Therefore, experts recommend using a separate fire control panel with the ability to control automatic fire extinguishing installations and voice warning.

Autonomous fire extinguishing systems It is most effective to install in places where fire is especially dangerous and can cause irreparable damage. Autonomous installations must include storage and supply devices fire extinguishing agent, fire detection devices, automatic start devices, means of signaling a fire or installation activation. Based on the type of fire suppressant, systems are divided into water, foam, gas, powder, and aerosol.

sprinkler And deluge automatic fire extinguishing systems used to extinguish fires over large areas with water using finely sprayed streams of water. In this case, it is necessary to take into account the possibility of indirect damage associated with the loss of consumer properties of equipment and (or) goods when wet.

Foam fire extinguishing systems They use air-mechanical foam for extinguishing and are used without restrictions. The system includes a foam mixer complete with piping and a dosing tank with an elastic container for storing and dispensing foam concentrate.

Gas fire extinguishing systems used to protect libraries, computer centers, bank depositories, and small offices. In this case, additional costs may be required to ensure proper tightness of the protected object and to carry out organizational and technical measures for the preventive evacuation of personnel.

Powder fire extinguishing systems are used where it is necessary to localize the source of the fire and ensure the safety of material assets and equipment not damaged by the fire. Compared with other types of self-contained fire extinguishers, powder modules are characterized by low price, ease of maintenance, environmental safety. Most powder fire extinguishing modules can operate both in electric start mode (based on signals from fire sensors) and in self-start mode (when the critical temperature is exceeded). In addition to the autonomous mode of operation, as a rule, they provide the possibility of manual start. These systems are used to localize and extinguish fires in confined spaces and in the open air.

Aerosol fire extinguishing systems– systems that use finely dispersed solid particles for extinguishing. The only difference between an aerosol fire extinguishing system and a powder one is that at the moment of operation an aerosol is released, not a powder ( bigger size, rather than an aerosol). These two fire extinguishing systems are similar in function and operating principle.

The advantages of such a fire extinguishing system (such as ease of installation and installation, versatility, high extinguishing capacity, efficiency, use at low temperatures and the ability to extinguish live materials) are primarily of an economic, technical and operational nature.

The disadvantage of such a fire extinguishing system is the danger to human health. The service life is limited to 10 years, after which it must be dismantled and replaced with a new one.

Another important element of OPS is alarm notification. Alarm Notification can be carried out manually, semi-automatically or automatically. The main purpose of the warning system is to warn people in the building about a fire or other emergency and control their movement to a safe area. Notification of a fire or other emergency situations should be significantly different from notification of a security alarm. Clarity and uniformity of information in a voice announcement are critical.

Warning systems vary in composition and operating principle. Controlling the operation of blocks analogue warning system carried out using a matrix control unit. Control digital public address system usually implemented using a computer. Local warning systems broadcast a previously recorded text message in a limited number of rooms. Typically, such systems do not allow for prompt evacuation control, for example, from a microphone console. Centralized systems automatically broadcasts a recorded emergency message to predetermined zones. If necessary, the dispatcher can transmit messages from the microphone console ( semi-automatic broadcast mode).

Most fire warning systems are built on a modular basis. The procedure for organizing a warning system depends on the characteristics of the protected object - the architecture of the object, the nature of production activities, the number of personnel, visitors, etc. For most small and medium-sized objects, fire safety standards specify the installation of warning systems of the 1st and 2nd types (sound and light signals in all areas of the building). In warning systems of types 3, 4 and 5, one of the main methods of notification is voice. The choice of the number and power of activation of sirens in a particular room directly depends on such fundamental parameters as the noise level in the room, the size of the room and the sound pressure of the installed sirens.

As sources sound signals For alarms, loud bells, sirens, speakers, etc. are used. The most commonly used lights are “Exit” light boards, “Direction of movement” light signs, and flashing light annunciators (strobe flashes).

Typically, the alarm controls other security features. For example, in the event of an unusual situation, seemingly ordinary announcements can be transmitted between advertising messages, which in conventional phrases inform the security service and enterprise personnel about incidents. For example: “Guard on duty, call 112.” The number 112 could mean a potential attempt to carry unpaid clothes out of the store. In emergency circumstances, the warning system must ensure control of the evacuation of people from premises and buildings. In normal mode, the public address system can also be used to broadcast background music or advertisements.

Also, the warning system can be integrated in hardware or software with an access control system, and upon receiving an alarm pulse from sensors, the warning system will issue a command to open the doors of additional emergency exits. For example, if a fire occurs, an alarm signal activates the automatic fire extinguishing system, turns on the smoke removal system, turns off the forced ventilation of the premises, turns off the power supply, automatically dials the specified telephone numbers (including emergency services), turns on the emergency lighting, etc. d. And when an unauthorized entry into the premises is detected, the automatic door locking system is triggered, SMS messages are sent to a cell phone, messages are sent via pager, etc.

Communication channels in the fire alarm system can be specially laid wire lines or telephone lines, telegraph lines and radio channels already available at the facility.

The most common communication systems are multi-core shielded cables, which, to increase the reliability and safety of alarm operation, are placed in metal or plastic pipes or metal hoses. The transmission lines through which signals from detectors are received are physical loops.

In addition to traditional wired communication lines, alarm and fire alarm systems today offer security and fire alarms that operate using a radio communication channel. They are highly mobile, commissioning work is kept to a minimum, and rapid installation and dismantling of the alarm system is ensured. Setting up radio channel systems is very simple, since each radio button has its own individual code. Such systems are used in situations where it is impossible to lay a cable or it is not financially justified. The stealth nature of these systems is combined with the ability to easily expand or reconfigure them.

We also must not forget that there is always a danger of intentional damage to the electrical circuit by an attacker or interruption of the power supply due to an accident. And yet, security systems must remain operational. All fire and security alarm devices must be provided with uninterrupted power supply. The power supply of the security alarm system must have redundancy capabilities. If there is no voltage in the network, the system must automatically switch to backup power.

In the event of a power outage, the operation of the alarm system does not stop due to the automatic connection of a backup (emergency) power source. To ensure uninterrupted and protected power supply to the system, sources are used uninterruptible power supply, batteries, backup power supply lines, etc. The use of a centralized backup power source leads to losses in the usable capacity of backup batteries, additional costs for wires of increased cross-section, etc. The use of backup power sources distributed throughout the facility does not allow monitoring their condition. To implement their control, a power source is included in the addressable fire alarm system with an independent address.

It is necessary to provide for the possibility of duplicating power supply using different electrical substations. It is also possible to implement backup power supply line from your generator. Fire safety regulations require that security and fire alarm could remain operational in the event of a loss of mains power for 24 hours in standby mode and for at least three hours in alarm mode.

Currently, the integrated use of fire alarm systems is used to ensure the security of a facility with a high degree of integration with other security systems such as access control systems, video surveillance, etc. When building integrated security systems, compatibility problems with other systems arise. To combine security and fire alarm systems, warning systems, access control and management, CCTV, automatic fire extinguishing installations, etc., software, hardware (is the most preferable) and the development of a single finished product are used.

Separately, it should be mentioned that Russian SNiP 2.01.02–85 also requires that evacuation doors of buildings do not have locks that cannot be opened from the inside without a key. In such conditions, special handles are used for emergency exits. Anti-panic handle ( Push Bar) is a horizontal bar, pressing which at any point causes the door to open.

Fire alarm (FS) is a set of technical means, the purpose of which is to detect fire, smoke or fire and promptly notify a person about it. Its main task is to save lives, minimize damage and preserve property.

It may consist of the following elements:

• Fire alarm control device (FPKP)– the brain of the entire system, exercises control over loops and sensors, turns on and off automation (fire extinguishing, smoke removal), controls sirens and transmits signals to the remote control of a security company or a local dispatcher (for example, a security guard);
• Various types of sensors, which can react to factors such as smoke, open flame and heat;
• Fire alarm loop (SHS)– this is the communication line between sensors (detectors) and the control panel. It also supplies power to the sensors;
• Annunciator- a device designed to attract attention, there are light - strobe lamps, and sound - sirens.

According to the method of control over loops, fire alarms are divided into the following types:

PS threshold system

It is also often called traditional. The operating principle of this type is based on changing the resistance in the fire alarm system loop. Sensors can only be in two physical states "norm" And "fire" If a fire factor is detected, the sensor changes its internal resistance and the control panel issues an alarm signal on the loop in which this sensor is installed. It is not always possible to visually determine the location of the trigger, because in threshold systems, an average of 10-20 fire detectors are installed on one loop.

To determine the fault of the loop (and not the state of the sensors), an end-of-line resistor is used. It is always installed at the end of the loop. When using fire tactics “PS triggered by two detectors”, to receive a signal "attention" or "possibility of fire" An additional resistance is installed in each sensor. This allows the use of automatic fire extinguishing systems at the facility and eliminates possible false alarms and property damage. The automatic fire extinguishing system is activated only in the event of simultaneous activation of two or more detectors.

PPKP “Granit-5”

The following PPCPs can be classified as threshold type:

• "Nota" series, produced by Argus-Spectrum
• VERS-PK, manufacturer VERS
• devices of the “Granit” series, manufactured by NPO “Sibirsky Arsenal”
• Signal-20P, Signal-20M, S2000-4, manufacturer of NPB Bolid and other fire-fighting devices.

The advantages of traditional systems include ease of installation and low cost of equipment. The most significant disadvantages are the inconvenience of servicing fire alarms and the high probability of false alarms (resistance can vary from many factors, sensors cannot transmit information about dust levels), the number of which can only be reduced by using a different type of substation and equipment.

Address-threshold PS system

A more advanced system is capable of automatically periodically checking the status of sensors. Unlike threshold signaling, the operating principle is based on a different algorithm for polling sensors. Each detector is assigned its own unique address, which allows the control panel to distinguish them and understand the specific cause and location of the malfunction.

The Code of Rules SP5.13130 ​​allows the installation of only one addressable detector, provided that:

• The PS does not control fire alarm and fire extinguishing installations or type 5 fire warning systems, or other equipment that, as a result of startup, can lead to material losses and reduced human safety;
• the area of ​​the room where the fire detector is installed is not larger than the area for which this type of sensor is designed (you can check it using the technical documentation for it);
• the performance of the sensor is monitored and in case of a malfunction a “fault” signal is generated;
• It is possible to replace a faulty detector, as well as detect it by external indication.

Sensors in addressable threshold signaling may already be in several physical states – "norm", "fire", "malfunction", "attention", "dusty" and others. In this case, the sensor automatically switches to another state, which allows you to determine the location of a malfunction or fire with the accuracy of the detector.

PPKP “Dozor-1M”

The address-threshold type of fire alarm includes the following control panels:

• Signal-10, manufacturer of airbag Bolid;
• Signal-99, produced by PromServis-99;
• Dozor-1M, manufactured by Nita, and other firefighting devices.

Addressable analog system PS

The most advanced type of fire alarm to date. It has the same functionality as addressable threshold systems, but differs in the way it processes signals from sensors. The decision to switch to "fire" or any other condition, it is the control panel that accepts it, and not the detector. This allows you to adjust the operation of the fire alarm to external factors. The control panel simultaneously monitors the status of the parameters of installed devices and analyzes the received values, which can significantly reduce the likelihood of false alarms.

In addition, such systems have an undeniable advantage - the ability to use any address line topology - tire, ring And star. For example, if the ring line is broken, it will split into two independent wire loops, which will fully retain their functionality. In star-type lines, you can use special short-circuit insulators, which will determine the location of the line break or short circuit.

Such systems are very convenient to maintain, because Detectors that require purging or replacement can be identified in real time.

The addressable analogue type of fire alarm includes the following control panels:

• Two-wire communication line controller S2000-KDL, manufactured by NPB Bolid;
• Series of addressable devices “Rubezh”, manufactured by Rubezh;
• RROP 2 and RROP-I (depending on the sensors used), manufactured by Argus-Spectrum;
• and many other devices and manufacturers.

Scheme of an addressable analogue fire alarm system based on PPKP S2000-KDL

When choosing a system, designers take into account all the requirements of the customer’s technical specifications and pay attention to the reliability of operation, the cost of installation work and the requirements for routine maintenance. When the reliability criterion for a simpler system begins to decrease, designers move to using a higher level.

Radio channel options are used in cases where laying cables becomes economically unprofitable. But this option requires more money for maintenance and maintaining devices in working condition due to periodic replacement of batteries.

Classification of fire alarm systems according to GOST R 53325–2012

Types and types of fire alarm systems, as well as their classification are presented in GOST R 53325–2012 “Fire fighting equipment. Fire automatic equipment. General technical requirements and test methods".

We have already discussed addressable and non-addressable systems above. Here we can add that the former allow the installation of non-addressed fire detectors through special extenders. Up to eight sensors can be connected to one address.

Based on the type of information transmitted from the control panel to the sensors, they are divided into:

• analog;
• threshold;
• combined.

According to the total information capacity, i.e. The total number of connected devices and loops are divided into devices:

• low information capacity (up to 5 shs);
• average information capacity (from 5 to 20 shs);
• large information capacity (more than 20 shs).

According to information content, otherwise according to the possible number of notifications issued (fire, malfunction, dust, etc.) they are divided into devices:

• low information content (up to 3 notices);
• medium information content (from 3 to 5 notices);
• high information content (from 3 to 5 notices);

In addition to these parameters, systems are classified according to:

• Physical implementation of communication lines: radio channel, wire, combined and fiber optic;
• In terms of composition and functionality: without the use of computer technology, with the use of computer technology and the possibility of its use;
• Control object. Management of various fire extinguishing installations, smoke removal means, warning and combined means;
• Expansion possibilities. Non-expandable or expandable, allowing installation in a housing or separate connection additional components.

Types of fire warning systems

The main task of the warning and evacuation control system (WEC) is to timely notify people about a fire in order to ensure safety and prompt evacuation from smoke-filled rooms and buildings to a safe area. According to Federal Law-123 “ Technical regulations on fire safety requirements" and SP 3.13130.2009, it is divided into five types.

The first and second types of SOUE

Most small and medium-sized facilities, according to fire safety standards, must install the first and second types of warning.

Moreover, for the first type it is characterized mandatory presence sound annunciator - siren. For the second type, “exit” light signs are added. A fire alarm must be triggered simultaneously in all premises with permanent or temporary occupancy.

The third, fourth and fifth types of SOUE

These types refer to automated systems, the triggering of an alert is completely assigned to automation, and the role of a person in managing the system is reduced to a minimum.

For the third, fourth and fifth types of SOUE, the main method of notification is speech. Pre-developed and recorded texts are transmitted that allow evacuation to be carried out as efficiently as possible.

In the 3rd type additionally, illuminated “exit” signs are used and the order of notification is regulated - first to service personnel, and then to everyone else according to a specially designed order.

In the 4th type there is a requirement for communication with the control room inside the warning zone, as well as additional light indicators for the direction of movement. Fifth type, includes everything that is listed in the first four, plus the requirement for separate inclusion of light signs for each evacuation zone is added, full automation of control of the warning system is provided and the organization of multiple evacuation routes from each warning zone is provided.