Types of fire alarm and communication. Type and view of fire alarm in school. Fire alarm automatic fire link and alarm

One of the conditions for successful struggle against fires is timely detection, early warning fire services and the beginning of active fire extinguishing at the initial stage of fire development. These tasks are solved by fire and alarm. Fire relationship provides a fire notice and challenge fire services, dispatching for the management of the forces and means of fire extinguishing and the operational connection of units during the extinguishing of a fire. The fire link is carried out on a city or special telephone network, or shortwave receiving-transmitting systems.

Fire alarm is used for early detection of sunbathing and reporting on the place of its occurrence and consists of detectors, linear communication and receiving station.

Fire alarm systems can be both automatic and manual action. Depending on the method of connecting detectors with the receiving station with the receiving station, the fire alarm is ray (radial) or loop (ring) system.

Electric fire alarm detectors - devices reacting to smoke, radiant energy, heat, ionization, the signal of which is transmitted to the receiving station, as well as on the inclusion of stationary fire extinguishing installations.

The triggering of detectors depending on their types can occur automatically or with manual inclusion,

Manual type detectors have a simple contact device and are powered by pressing the start button. The manual detectors of the PKIL-7 button of the push-button are placed on noticeable places in buildings and production workshops. To serve a fire signal, you should smash the glass and press the detector button with hand.

Automatic detectors convert non-electrical values \u200b\u200binto an electrical signal. According to the principle of operation, the converters are divided into parametric, in which no electrical values \u200b\u200bare converted into electrical using auxiliary current source, and generator, in which the change in non-electrical value causes the appearance of its own electromotive force.

Depending on how the phenomenon is reacting automatic detectors (sensors), they are divided into the following types:

1) thermal fire detectors responding to temperature increase;

2) sensors reacting to smoke or gaseous combustion products;

3) sensors reacting to light radiation (flame, spark);

4) Combined sensors in which several types of sensitive elements are used based on various transformation principles.

Automatic fire detectors, in turn, are divided into three groups:

a) maximum action sensors that are triggered by the controlled parameters (smoke, temperature, radiation) of a certain value;

b) Differential detectors react to the speed of changes in the controlled parameter;

c) Maximum differential - react as an absolute value of the controlled parameter and the speed of its change.

Thermal sensors of the maximum action (type atim, ATP) are triggered when the ambient temperature is reached - 50, 70,100, 140 ° C. As a sensitive element, smelly or combustible (celluloid) inserts, mercury, liquid or bimetallic links, as well as electrical devices operating on the principle of changing the electrical conductivity of the circuit parts are used.

Sensor thermal light-melting DTL (Fig.16.18) was distributed due to the simplicity of the design and the possibility of connecting to the installation of a fire alarm. The sensitive element of the sensor is formed by two spring plates 2, soldered at one end of the Wood alloy 1 (tin + cadmium + bismuth + lead), with a melting point of 72 ° C. The second ends of the plates are strengthened on the plastic base 3 and connected to an electric clamp 4. When the temperature is raised, the spay is melted and the plates are diverged, the erosion chain of alarm.

Thermal Likers of TRV Type Maximum Action (Fig.16.19) have an explosive version and are installed in explosive rooms of all classes. The principle of operation is based on the difference in linear elongations when heating the brass tube and an inquar rod. These detectors serve not only for signaling about increasing the temperature above the permissible (the threshold of the various modifications of the TRV is 70 and 120 ° C), but also for starting automatic fire extinguishing systems.

Differential detectors react to temperature growth rate, regardless of temperature in the protective room. For example, the DPS-038 fire alarm sensor, as a sensitive element, has a battery of 50 thermocouples and works on the principle of the difference in the thermoelectro-lived force on a shredded and silver spoon of thermocouple. The detector is triggered with a rapid temperature increase (at least 30 ° 7 p.). The estimated room maintenance area is up to 30 m 2.

Terrokeepers, as a rule, are inertial, i.e. For triggering, they need some time (from 50 to 120 p.). Often the fire is preceded by a distance. The initial phase of the fire can last a few hours. In this case, the fire alarm system, the action of which is determined by increasing the temperature or the presence of open fire, can signal the fire only after it, reaching the highest phase of development, will quickly spread. Therefore, in fire alarm systems, detectors respond to the appearance of smoke or gaseous combustion products are often used. The sensitive element of such minority detectors are photocells, photon counters or ionization chambers.

The principle of operation of the flue detectors is based on the change in the optical properties of the medium when smoke appears and can be carried out by two methods: i) on the weakening of the primary light flux; 2) by the intensity of the reflected (scattered) particles of the smoke of the light flux.

The first method is used in linear optical electronic security and fire detectors, the second - in the detectors of the types of IDF and DIP.

The detector of the smoke photovoltaic IDF consists of an optical node containing a light source and a photodetector, and a semiconductor amplifier (Fig.16.20).

In the standby mode, the light does not fall on the photoresistor, and when the smoke appears, light scattering and the photoresistor resistance decreases, which leads to a triggering of the amplifier and issuing alarm signal.

A similar principle is used in DIP-1 and DIP-2 detectors. To ensure stability to background illumination, they use a method for modulating a light source with pulses from a multivibrator. The detector works only when the light smoke particles are reflected from the modulated source. An extraneous light source cannot cause a false response of the detector.

Similar information.

Responsibilities of officials on the organization of communication. Discipline and communication rules.

Dispatcher (radiotelephone) PSH It is subject to the head of the guard of the GPS division, and in operational attitude - the dispatcher of the garrison. It is responsible for clear reception, transmission and registration of messages entering the field of communication part, timely expulsion of units for fires, accidents of accidents and natural disasters. He is obliged:

to know the operational fire in the area of \u200b\u200bdeparture of the GPS units, the list of objects to which operational plans and fire extinguishing cards are drawn up or sent during the fire of units at an elevated call number, anhydrous sections, the location of important and fire-hazardous facilities, travel and water sources, as well as basic tactical Technical data of fire trucks (ships, trains) available in the garrison;

be able to quickly accept fire messages and use PSH reference documentation;

check the operation of communications and alarm on the PSE when interpreted on duty, and periodically, in the process of duty, contain them in cleanliness and health, about all faults report to the head of the guard and the dispatcher of the garrison;

maintain communication with the services of the district (objects), interacting with the fire unit, and, if necessary, send the forces and funds of these services to the fire area (accident, natural disaster) in accordance with the established procedure;

upon receipt of reports on the closure of travel, the failure of fireproof water supply, on violations of communication and other changes in the operational fire situation immediately report to the head of the guard and the dispatcher of the garrison;

when calling on the phone answer: "Fire Protection";

having received a message about the fire, without interrupting the conversation, turn on the alarm, and at night and additional lighting of the premises, fill the ticket to the departure of the guard and its copies by the number of traveling offices, set the address of the fire, surname and the applicant's phone number, and if possible - other information about the fire that can affect the successful extinguishing of the fire;

hand the ticket to the head of the guard, informing it the available information about the facility and the nature of the fire, one copy of the ticket to leave himself;

together with a ticket (token) for departure to hand the head of the guard operational card (plan) of fire extinguishing (if such a thing has been developed);

when receiving an alarm signal from the fire alarm detector to give a reverse signal, take the detector tokens, thoroughly verify the gate numbers with the numbers of the detector and transfer them to the Karaul head;

when an alarm signal is received from the installation of a fire alarm, checkout the departure of the guard as well as upon receipt of the notice by phone;

upon receipt of a fire message at the facility to which the automatic expulsion of forces and funds are provided at an increased call number, immediately report this to the garrison dispatcher;

about the departure of the guard, the direction of additional forces and funds, information received from the place of work of the guard, about the return of Karaul inform the dispatcher of the garrison and officials in the prescribed manner;

install and maintain a connection with the guard, who left for a fire (to the place of accident, natural disaster, on practical classes), taking into account the features of the object to find out with the help of reference documentation, as well as through the relevant services the operational and tactical features of the object, the level of gas supply, the radiation situation, Estimated changes of meteo conditions, etc. and upon receipt of additional information, immediately reports about the dispatcher of the garrison and the Karaul head;

take all necessary measures to obtain information about the situation from the place of operation of the GPS division and immediately transfer the instructions and information to the TSUS;

upon receipt of a fire notice outside the field of departure of this unit, the GPS immediately transfer it to the TSUS or to the GPS unit, in the area of \u200b\u200bthe protection of which there was a fire, and report this to the head of the Karaul;

to record a part of the connection point of part and the content of messages (indicating the names of reporting fires, accidents, natural disasters, about the failure of hydrants, plumbing networks, roads, travel, means of communication, etc.), orders and messages from fire , accidents, natural disasters, departure time, arrival to the place of call and returning the guard of the guard (including classes and exercises), to whom from officials, when and which information is transmitted, what and when done by the reports received and in the execution of orders received etc.;

keep records of objects with a round-the-clock stay of people (kindergartens, medical institutions, etc.);

to allow only the head of the guard and his direct supervisors, as well as those responsible for maintenance of communication equipment.

Radiotelephone operating with a wearable radio station, obeying the head of the guard (commander of the department) and the face, which is directed. He is obliged:

establish and maintain communication with firewalls running on fire;

know call signs working on a fire of radio stations;

have a pencil and notepad for recording.

Radio telephone playerSubordinates the head of the guard (commander of the department) and the person, which is directed, and is responsible for the serviceability of the phone, timely establishment and uninterrupted operation of the communication line. He is obliged:

after laying the line and turn on the telephone, check their serviceability, report to the switch;

know the number of the switch subscribers;

not to be removed from the device, waiting for a call signal from the switch;

when calling, answer: "1 plot (for example, the Ivanov site) listens", after which it is to join the conversation;

negotiations lead briefly, without unnecessary words and only on official issues;

prevent phone use by unauthorized persons;

upon receipt by telephone orders quickly and accurately transfer them to the addressee;

immediately notify the P / telephonist operating on the switch, on the transfer of the device to a new place and temporary termination;

carefully handle the telephone and protect it from dust and moisture;

have a notebook to record messages.

Rules for radio exchange.

Messaging provides for the transfer and reception of telephones, radiograms, telegrams, graphic and text images, signals, commands, etc.

The content of the message is divided into operational and service. The exchange of operational messages is made on the management of GPS units and livelihood services in their combat activities. The exchange of service messages is made in establishing and verifying communication and in solving issues of administrative and economic activity of the garrison.

Messaging should be brief. Making a different kind of private queries and private negotiations between subscribers is strictly prohibited.

The list of questions on which the posts are exchanged by the open text is determined by the headpover head (OGPS).

Communication is carried out in shape: "Angara! I'm falcon! Answer", "Falcon! I'm hangar! Reception!".

If you need to transmit messages, the calling subscriber after establishing communication transmits it in shape: "Angara! I'm falcon! Take a message" (hereinafter follows the text), "I'm falcon, reception!". About receiving a message is given in shape: "Falcon! I am the hangar" (Repeated Text Messages), I'm hangar, reception! ".

On the end of the communication, the operator notifies the words: "End of Communication". Message transfer must be carried out leisurely, distinctly distinct. It is necessary to speak with a full voice, but do not shout, since the clarity and clarity of transmission is disturbed.

With bad hearing and ambiguity, hard-acting words are transmitted according to the letters, and each letter is transmitted by a separate word according to the following table:

A - Anna	L - Leonid	C - Heron
B - Boris	M - Mikhail	H - man
In - Vasily	N - Nikolai	Sh - Shura
G - Grigory	Oh Olga	Shch - Pike
D - Dmitry.	P - Pavel	Eho
E - Elena	R - Roman	Yu - Yuri.
Well - Zhenya	C - Semen.	I - Yakov
3 - Zinaida	T - Tatyana	S - Era
And - Ivan.	U - Ulyana	B - Soft Sign
Y - Ivan Short	F - Fedor	Kommersant - solid sign
K - Konstantin	X - Khariton

Digital text transmission is made according to the following rules:

Three-digit groups 126, 372 - one hundred twenty six, three hundred seventy-two, etc.;

Four-digit groups 2873, 4594 - twenty-eight seventy three; forty five ninety four, etc.;

Five-digit groups 32481, 76359 - thirty-two four hundred eighty one; seventy-six three hundred fifty-nine, etc.;

With bad heard, each figure is allowed to transmit words: unit, twice, triple, four, five, six, seven, eight, nine, zero.

When transferring from a place of fire, you must follow the following exemplary messages texts:

- "arrived at the call site. Intelligence

- "Lights on the attic of a four-story house. Send an additional auto expense."

- "Profit to the call site, closing electrical storage. Send the emergency service of the power grid."

- "Fire is eliminated, disassembly"

Evaluation of the quality of communication is made on a five-point system:

5-excellent connection (nozzles are not auditioned, words of layming up);

4-good connection (interference is tested, words of layming up);

3-satisfactory communication (interference is strongly listened, the intelligibility is insufficient);

2-unsatisfactory communication (interference is so great that words are dealt with difficulty);

1 reception is impossible.

If you fail to respond from the called subscriber to three consecutive calls within 1-2 minutes, the dispatcher (radiotelephone) is obliged to report on the TSUS on the absence of communication.

All radio stations should work only on the frequency channels allocated. Work on other frequency channels, except in cases of entry in the radio network of life support services.

The callsign radio stations are appointed by technical departments (departments) of the Ministry of Internal Affairs, the GUVD, the Department of Internal Affairs of the Russian Federation. The purpose of arbitrary callsigns is categorically prohibited.

Before starting the transmission of the radio operator by listening to the frequency of your transmitter, make sure that this frequency is not occupied by other subscribers of the network.

To intervene in radio exchange between two radio stations is permitted only by the main radio stations and radio stations operating at the fireplace, if necessary, calling additional forces and ads of an increased fire number.

The radio checking is allowed only by transmitting the words of the sequence account: "I give an account to configure: one, two, three, four, five ...". Verify the radio channel with an increased call number and disaggregated.

Work on GPS radio stations is allowed only to persons who have passed special training and having an appropriate permission of the headpover (OGPS).

Call processing and reception information.

Call processing is carried out in the prescribed manner of the dispatcher (radiotelephone) of the fire protection unit and includes:

Reception from the applicant and fixing the information about the fire;

An assessment of the information received and the decision on the direction of the call to the call of forces and means provided for by the departure schedule (plan to attract forces and means);

Filing an alarm signal;

Preparation and presentation (transfer) The official leading the duty guard or duty shift (hereinafter referred to as the head of the guard), tickets about the departure for fire, as well as, if necessary, operational plans (cards) of fire extinguishing and other information about the burning facility.

When receiving information from the applicant about the fire, the dispatcher must be fully installed if possible:

The presence and nature of the danger of life and health of people;

The features of the object on which the fire originated;

Surname, name, patronymic of the applicant;

Other information (including the applicant's phone number) about the fire, which may affect the successful performance of the main combat.

The alarm signal is submitted immediately after the address or other information about the place of fire and make a decision on the departure.

Call processing must be completed for a short time and not to deduct the departure and follow the place of fire.

If necessary and the availability of technical capabilities, information about the fire can be transferred to the manager of the head of the Karaul radio communication during its following to the place of fire.

The fastest and most reliable way to notify the emerged fire is the electrical fire alarm system (EPS).

The EPS consists of the following basic parts: detectors installed in the workshops, separations, in warehouses, etc.; The receiving station located in the duty room of the fire team and the electrically conductive network connecting detectors (manual or automatic) installed on the objects with the receiving station.

Considering the dependence of the discharge, the connections are detectable with the EPS receiving station should be radial (radial) or loop (ring).

IN ray EPS system (Figure 5 A) Each detector 1 is connected with a receiving station 2 with two wires 6 forming a separate beam.

Figure 5. Scheme of the EPS system device:

1 - sensors detectors; 2 - receiving station; 3 - a backup power supply; 4 - power supply unit; 5 - switching system from one power to another; 6 - wires.

When you click on the button of one of these manual detects, or the automatic detector is triggered at the receiving station, a signal indicates the beam number, ᴛ.ᴇ. Fire place. The receiving apparatus on the principle of action is similar to the telephone switch.

IN loop The EPS system (Figure 5 b) of the ALL detectors 1 are connected to the receiving station 2 in series by one common wire 6. When the detector is triggered, except for a sound or light alarm, the detector number, time and date of receipt of the signal and the receiving machine are recorded on the tape An automatic translation of the alarm to the central station is performed. In case of damage to the network, it is noted at the station by a special signal. Recently, the smaller application has been found in the installation of fire alarm with manual detectors, and due to low reliability, the manufacture of EPS loop systems has ceased.

The EPS of the enterprise or a separate area is operating from manual and automatic detects and is automatically connected with the city EPS. The most common detectors of the radiot system are bird type detectors (automatic thermal detector of maximum action), MDPI-028 (Maximum-differential fire detector), PKIL-9 (firepad radial detector), etc.

Sensitive elements Automatic detects are: thermal - they react to an increase in temperature (heat-sensitive); Light - react to open fire (sparks, flames) and smoke - react to the appearance of smoke.

Terroh Likers According to the principle of operation, it is divided into: maximum, triggering when the controlled parameter (temperature, radiation) of a certain value is reached; Differential, responding to the speed of change of the controlled parameter; Maximum differential, reacting both to achieve a controlled parameter of a given value and the rate of its change. Terrokeepers, which, after the triggering and setting normal temperatures, return to its original position without outside intervention, are called self-refining.

Due to the simplicity of the design, the detector (sensor) thermal light-melting - DTL (Figure 6 b) was greatly distributed. As a sensitive element, an alloy is used in it, with a melting point of 72 ° C, which connects two spring plates. With an increase in temperature, the alloy is melted, and spring plates, blurring, include alarm circuit.

Figure 6. Detectors

a, b - thermal sensors; B - Thermal Liker Atim: 1 - bimetallic plate; 2 - base; 3 - rod; 4 - contact screw.

For instant receipt of the alarm at the very beginning of fire, the appearance of flame flame, smoke, etc. Currently, mining detectors with photocells, photon meters, ionization chambers, etc. are applied.

For example, in the detectors of the SI-1 type responding to the ultraviolet rays of the open flame, semiconductor photocells are used. It is important to note that it is sufficient to appear the electrical spark or flame matches to respond to such a detector. They do not work from lighting lamps, but should be protected from direct sunlight from entering them.

Detectors reacting to smoke are based on the use of photoelectric and ionization sensors.

Today, new fire detectors type detectors (Dip-1, Dip-2), designed to detect smoke, operating on the principle of registration with a photodetector reflected from light smoke particles and radioisotope detectors of the RID-type smoke (RID-1, RID-6M), Which as a sensitive element have an ionization chamber.

A successful struggle with the emerging fire depends on the rapid and accurate transfer of the message about the fire and the place of its occurrence of the local fire team, which allows it to quickly eliminate and significantly reduce the amount of damage. Until now, in some remote areas of the countryside, strikes are used in a bell or on a metal rail, as well as a telephone connection. The company's sound systems of the enterprise include beep, siren, etc. Currently, electrical and automatic fire alarm systems are widely used, as well as radio and telephone communications.

The main elements of the electrical and automatic fire alarm are: detectors (sensors) installed on objects; receiving stations registering the resulting fire; Linear structures connecting detectors with receiving stations. The receiving stations are located in the nearest special premises of the fire fighting or at the locations of round-the-clock duty and provide signals from detectors, transform them into light and sound information, and if necessary, the inclusion of automatic fire extinguishing agents.

Electrical fire alarm (EPS) allows you to quickly and safely feed the alarm, fix the signal, provides double-sided conduction between detectors and a receiving station. Button detectors acting from handpap must be located in the available places: lobby, corridors, staircases, etc.

According to the inclusion schemes, the EPS is divided into radiation and loop. In the radiation scheme (Fig. 7.7, but) From the station to the detector goes rays consisting of two wires - direct and reverse. The radiation system is used, usually in cases where there is a small length of the line or a telephone cable is used.

Receiver

Detectors

Line loop

Fig. 7.7. Electrical fire alarm scheme: but - radiation; b. - Loop

Travel alarm system (Fig. 7.7, b) It is a ring in which code detectors are consistently included, forming one common wire - the loop.

The most reliable and fast fire notification system is the automatic fire alarm system of the APS, which without the participation of a person allows you to detect the emerging fire and notify the receiving station about it. This system is applied to facilities hazardous facilities (bases, warehouses, trade enterprises). According to the method of perception of the primary impulse, automatic detectors are divided into heat, light and combined (smoke and thermal),

/ - barrel with water; 2 - fire buckets; 3 - Writing fire hoses; 4 - fire extinguisher OP-5; 5 - hydropult-bucket; 6 - carbon dioxide fire extinguisher OU-2; 7 - shovels; 8- sandbox; 9 - Bagra; 10- scrap; 11 - Fire axes

optical and ultrasound, which are installed under the ceiling of the premises.

Heat detectors There are different models and are triggered under the influence of an increased source of heat (convection or radiant), emanating from the fire focus. In the thermal sensor, the sensitive element is bimetallic plates. At a temperature of 80 ° C, the plate is bent, the erosion chain of the alarm. Square controlled by one sensor - up to 15 m.

IN light Detectors (photocells) uses photo effects phenomenon. These detectors react to the ultraviolet or infrared part of the spectrum of open flame radiation. In case of fires, along with heat transfer, thermal conductivity and convection of the medium, thermal radiation occurs due to hot solid and gaseous substances.

Smoke sensors (Detectors) serve to supply a signal about fire danger when smoke appears in closed rooms.

They are ionization chambers and are triggered with an increased concentration of smoke indoors.

Combined The detectors are a combination of flue and thermal sensors (ionization chamber and thermistors), which are shown on an increased smoke concentration or light stream.

Ultrasound Sensors are designed to detect in the premises of moving objects (oscillating flames). One such sensor controls the area to 1000 m.

To ensure trouble-free operation of detectors, it is necessary to monitor their good condition. The head of the enterprise is responsible for organizing the operation and technical content of fire alarm systems.

Primary fire extinguishing tools used to extinguish small foci of rumor before the arrival of fire teams are located on special shields (Fig. 7.8), which should be located in convenient locations: on the territory of the household courtyard, in the premium spaces and should not be lit by the package, garbage and Other objects.

They have various tools (shaft) and means for extinguishing a fire. Means for extinguishing fires and tools should be painted in red, and inscriptions about their accessories make white paint.

In enterprises, with the aim of timely alert about the emergence of fire, the inclusion of fire extinguishing systems and the call of firefighters provides for a fire supply system and alert.

Depending on the purpose, the fire alarm system is distinguished for the alerts of fire protection of the enterprise or city; Dispatcher communication, ensuring the management and interaction of fire units with the administration of districts and urban emergency services and operational radio, which "directly manages fire offices and calculations when steaming fire.

One of the types of fire range - telephone connection. Each telephone is strengthened with a sign indicating phone numbers to call fire protection. In compulsory telephone connection, the premises of the fire post, duty personnel, dispatch communication, as well as other premises with staff leading round the clock duty are equipped.

Fire alarm is designed for a quick message about the fire. Fire alarm systems are equipped with technological installations of increased fire hazard, industrial and administrative buildings, warehouses. Fire alarm can be electrical and automatic.

Electrical fire alarm Depending on the detector connection scheme, the receiving station can be radius and loop (ring) (Fig. 4.15).

When the fire alarm radiation system device, each detector is connected to the receiving station with two wires forming a separate beam.

At the same time, 3-4 detector is installed in parallel at each ray. When you trigger any of them at the receiving station, the beam number will be known, but not the place of installation of the detector.

The most common detectors of the radiot system are bird-type detectors (thermal detector of the maximum action), MDPI-028 (maximum-differential fire detector), PKIL-9 (fire button radius detector) and others.

Curly (ring) System When installing manual detectors, it usually provides for inclusion of about 50 detectors sequentially onto one line (loop). Each detector, having a specific code and feeding the signal to the station simultaneously gives information about the place of its location. The fire team immediately leaves the place of operation of the detector.

Manual fire detectors can be installed both outside buildings on walls and structures at an altitude of 1.5 m from the floor level or ground and at a distance of 150 m from each other and indoors - in corridors, passages, on stairwells, if necessary in closed Premises. The distance between them should be no more than 50 m. They are installed one on all the staircases of each floor. The place of installation of manual fire detectors is illuminated with artificial light.

Surface sections on which the placement of manual detectors is provided, painted white with a red edging width of 20x50 mm (GOST 12.4.009). They should be included in an independent fire alarm loop or in conjunction with automatic fire detectors. To actuate the electrical fire alarm, it is necessary to smash the glass and click on the fire detector button.

Currently, manual fire detectors of IPR-1 brands, IP5 can be produced, etc.

Automatic detectors, i.e. Sensors that signal fire are divided into thermal, smoke, light and combined.

Thermal detectors (thermal lockers) are triggered by increasing the temperature to a specified limit. They are recommended to be installed in closed rooms. Terrokebooks on the principle of operation are divided into maximum, triggering when the controlled parameter is reached (temperature, radiation) of a certain value; Differential, responding to the speed of change of the controlled parameter; Maximum differential, reacting both to achieve a controlled parameter of a given value and the rate of its change.

Terrokeepers, which, after the triggering and setting normal temperatures, return to its original position without outside intervention, are called self-supporting.

Due to the simplicity of the design, the detector of the heat- "howling is light-melting - DTL (Fig. 4.16). As a sensitive element, it was used with a melting point of 72 ° C, which connects two spring plates. When the temperature is raised, the alloy is melted and plates, blurring. Include alarm network.

The flue detectors are used in the case when a large amount of smoke and combustion products are distinguished during the burning of substances. Detectors reacting to smoke are based on the use of photoelectric and ionization sensors. Fire detectors type DIP (dip-1, dip-2), operating on the principle of registration of the photodetector reflected from the light smoke particles, and radioisotope detectors of the RID-type smoke (RID-1, RID-6M), in which as Sensitive element applies ionization chamber.

Opto-electronic flue fire detectors were widespread in practice, IP212-41M, IP212-50M, IP212-43, IP212-45, IP212-41M and combined with a temperature sensor -IP212-5MS, IP212-5MK, IP212-5μs, etc. .

For instant receipt of the alarm at the very beginning of fire (with the appearance of flame, smoke, etc.), minority detectors with photocells, photon meters, ionization chambers, etc. are currently applied.

Smoke and thermal fire detectors are installed on the ceiling, it is allowed to install them on the walls, beams, columns, suspension on cables under the coatings of buildings.

Light detectors are applied in the case when visible flames appears when combustion. They can also be installed on the equipment.

Combined detectors are applied to protect the installations of increased reliability when several fire effects can be manifested simultaneously.

The number of automatic fire detectors installed is determined by the area of \u200b\u200bthe room, and for light detectors - and controlled equipment. Each point of the protected surface must be controlled by no less than two automatic fire detectors.

Fire tie and alarm are of great importance for measures to prevent fires, contribute to their timely detection and challenge fire units to the place of fire, and also provide management and operational guidance on fire.