Installation of aspiration fire alarm system. Aspiration detectors and their operating principle
Aspirating smoke detectors (AFDS) are new generation detectors that can provide fire protection fire protection objects to the maximum high level and under almost any operating conditions.
Unlike point and linear aspiration smoke detectors, there are no regulatory restrictions on the maximum level of sensitivity, and their operating principle and design features allow you to effectively protect the most complex objects. For example, areas with high speeds air flow, ceiling and underground spaces with extremely high or low temperatures, dusty and explosive areas, rooms with limited access, rooms with high ceilings, dome-shaped, with beams, etc. Possible hidden installation pipes in the ceiling space, in building structures or in decorative elements rooms with transparent capillary tubes to form remote air intake points.
Aspirating smoke detectors were invented by Xtralis over 30 years ago and have been featured on the market for over 20 years. Russian market. Until 2009, aspiration detectors were used according to the recommendations of VNIIPO, which were developed for aspiration detectors each specific type. In 2009, the requirements for the installation of aspirating smoke detectors were defined in the “Code of Rules SP 5.13130.2009 Systems fire protection. Settings fire alarm and automatic fire extinguishing systems. Design norms and rules." In the same year, GOST R 53325-2009 “Fire fighting equipment” was put into effect. Technical means fire automatics. Are common technical requirements. Test Methods”, in which the technical requirements and testing methodology for IPDA were first defined. These standards and requirements have been received further development in subsequent versions of these documents: in GOST R 53325-2012 and in SP 5.13130.2009 with Amendments No. 1.
Of greatest practical interest are Class A laser smoke detectors, which have currently achieved a fantastic sensitivity of 0.0002%/m (0.00001 dB/m). High sensitivity laser aspiration detectors provide the maximum level of fire protection in clean rooms, containment areas, operating rooms, computer magnetic resonance imaging, positron emission tomography rooms, pressure chambers, high rooms and areas with air flows: atriums, data centers , in the MCC, industrial workshops, in high-rise warehouses, etc. Highly sensitive laser IPDAs provide superior early detection fire danger, which determines minimal material losses, no need for evacuation and interruption of the enterprise. To ensure the possibility of rapid response by personnel, several pre-alarm and alarm signals are generated at different levels of smoke. Aspiration detectors with increased sensitivity of class B and class C with standard sensitivity, i.e., with the sensitivity of a point smoke detector, have a narrower scope of application.
Operating principle
According to GOST R 53325-2012, an aspiration fire detector is an “automatic fire detector that provides sampling through a pipe system with air intake holes and delivery of air samples (aspiration) from the protected room (zone) to a device for detecting a sign of fire (smoke, change chemical composition environment)" (Fig. 1). This principle of constructing a detector, unusual at first glance, with pipes with air intake holes and an aspirator, determines a lot of advantages compared to smoke point and linear detectors. Air samples from the controlled room enter the pipes due to the vacuum created by an aspirator, which, together with an optical density meter, is located in the processing unit.
I.G. Not bad
Head of Technical Support Department at System Sensor Fire Detectors, Ph.D.
General provisions
An aspirating smoke detector is a detector in which air and smoke samples are transported through a sampling device (usually through pipes with holes) to a smoke sensing element (a point smoke detector) located in the same unit as the aspirator, e.g. turbine, fan or pump (Fig. 1).
The main characteristic of an aspiration detector, like any smoke detector, is sensitivity (that is, the minimum value of the specific optical density in one of the samples at which the detector generates a “Fire” signal). It depends on the sensitivity of the point smoke detector used, as well as on the design of the sampling device, the number, size and location of holes, etc. It is important to ensure approximately the same sensitivity for different samples, that is, a balance in sensitivity. Other important characteristic aspiration detector, not taken into account for a point smoke detector, is transportation time, the maximum period of time required to deliver an air sample from the sampling point in the protected room to the sensitive element.
Test room
To determine the sensitivity of an aspiration detector according to the EN 54-20 standard, tests are carried out on test fires in a room measuring (9-11) x (6-8) m and a height of 3.8-4.2 m (Fig. 2), as with spot tests smoke detectors according to EN 54-7 standard. A test fire source is installed on the floor in the center of the room, and on the ceiling three meters from its center in a 60° sector there is an aspiration detector pipe with one air intake hole, as well as a meter for the specific optical density of the medium m (dB/m) and a radioisotope meter concentration of combustion products Y (dimensionless quantity).
It is allowed to test no more than two samples of aspiration detectors simultaneously, and their air intake openings must be located at a distance of at least 100 mm from each other, as well as from the elements of the measuring equipment. The center of the light beam of the optical density meter m must be at least 35 mm from the ceiling.
Test sites for point smoke detectors
Point fire smoke detectors according to the EN54-12 standard are tested against smoke from four test sources: TF-2 - smoldering wood, TF-3 - smoldering cotton, TF-4 - burning polyurethane and TF-5 - burning n-heptane.
The TF-2 fireplace consists of 10 dry beech blocks (humidity ~5%) measuring 75x25x20 mm, located on the surface electric stove with a diameter of 220 mm, having 8 concentric grooves with a depth of 2 mm and a width of 5 mm (Fig. 3). Moreover, the external groove should be located at a distance of 4 mm from the edge of the slab, the distance between adjacent grooves should be 3 mm. The power of the stove is 2 kW, the temperature of 600 °C is reached in approximately 11 minutes. All tested detectors must be activated at a specific optical density m of less than 2 dB/m.
The TF-3 hearth consists of approximately 90 cotton wicks, 800 mm long and weighing approximately 3 g each, suspended on a 100 mm diameter wire ring mounted on a tripod 1 m above a base of non-combustible material (Fig. 4). Cotton wicks should not have protective coating, if necessary, they can be washed and dried. The lower ends of the wicks are set on fire so that smoldering appears with a glow. All tested detectors must be activated at a specific optical density m of less than 2 dB/m. The TF-4 fireplace consists of three mats of polyurethane foam laid one on top of the other, containing no additives that increase fire resistance, with a density of 20 kg/m3 and dimensions of 500x500x20 mm each. The hearth is ignited from a flame of 5 cm3 of alcohol in a container with a diameter of 50 mm, installed under one of the corners of the lower mat. All tested detectors must be activated when the concentration of combustion products Y is less than 6. The TF-5 source is 650 g of n-heptane (purity not less than 99%) with the addition of 3% by volume toluene (purity not less than 99%) in a square pan made of steel measuring 330x330x50 mm. Activation is carried out by flame, spark, etc. All tested detectors must be activated when the concentration of combustion products Y is less than 6.
Classification of aspirating detectors
Aspirating detectors, unlike point smoke detectors, according to the EN54-20 standard are divided into three sensitivity classes:
- class A - ultrasensitive;
- class B - high sensitivity;
- class C - standard sensitivity.
Sensitivity limits for detectors of different classes according to various types test lesions are given in table. 1. Class C aspirating detectors are equivalent in sensitivity to point detectors and are tested using the same test centers. The only difference is that the end of the test is determined 60 seconds after reaching the boundary conditions. Obviously, this time is required to account for the time it takes to transport the sample through the pipe. Aspirating detectors of classes A and B have a significantly higher sensitivity compared to a detector of class C. For example, for test fires TF2 and TF3, the sensitivity of an aspirating detector of class B is 13.33 times higher, and class A is 40 times higher than that of Class C detectors and point smoke detectors. Such high performance are achieved through the use of laser point smoke detectors with a sensitivity of 0.02%/Ft (0.0028 dB/m) and higher as a smoke-sensitive element. In addition, taking air samples from the controlled room and creating a constant flow of air in one direction through the smoke chamber with an aspirator puts even a conventional optical detector in a more advantageous position than when installed on the ceiling, where efficiency is significantly reduced due to the significant aerodynamic resistance of the protective mesh and smoke chamber at low air speeds. Under conditions of constant air flow, the sensitivity of the smoke detector is more stable, and its value practically does not differ from the results of measurements in a wind tunnel according to NPB 65-97, which simplifies the design of fire alarm systems using aspirating fire detectors. Addressable analog aspiration detectors with programmable sensitivity can belong to several classes (A/B/C). In accordance with their range of measuring the specific optical density of the medium, they can generate, in addition to the “Fire” signal, one or more preliminary signals, for example “Attention” and “Warning”, at earlier stages of the development of a fire hazardous situation. A laser aspiration detector is essentially a high-precision meter of the optical density of the medium entering the central unit over a wide range. To adapt to different conditions operation and for programming several thresholds, usually about 10 discretes are sufficient (Table 2).
Test centers for aspirating detectors of classes A and B
To measure the sensitivity of aspiration detectors of classes A and B, test fires several times smaller in size are used. In test fires TF2A and TF2B, instead of 10 beech bars, only 4 or 5 bars are used (Fig. 5); in fires TF3A and TF3B, instead of 90 wicks, approximately 30-40 are used.
It is physically difficult to ensure slower development of a polyurethane foam lesion compared to the test lesion TF4, therefore lesions TF4A, TF4B are absent in the EN54-20 standard. It is much easier to form test lesions TF5A, TF5B with n-heptane: the dimensions of the tray and the volume of n-heptane used are reduced. Compared to the area of the TF5 test lesion, the area of the TF5B lesion is 3.56 times smaller, and the area of the TF5A lesion is 10.89 times smaller (Table 3). Reducing the size of the test spots alone for testing highly sensitive class B and ultra-high-sensitive class A aspiration detectors was not enough. To create minimum smoke concentrations under the ceiling in the test room, a ventilation system is installed (Fig. 6) at half the height of the room and at a distance of 1 m from the fire in the horizontal projection. When working ventilation system smoke from the test fire does not accumulate under the ceiling, but is evenly distributed throughout the entire volume of the room. Thus, reducing the size of the test source and the distribution of smoke throughout the room made it possible to ensure a slow increase in the optical density of the medium, which made it possible to measure with high accuracy the sensitivity of the aspiration detector at a level of less than 0.01 dB/m. As an example in Fig. Figure 7 shows the dependences of the specific optical density for the test lesion TF3A. It should be noted that the optical density when using test fires when measured in dB/m increases linearly, which makes it possible to evaluate the gain in time for determining a fire hazardous situation with increasing sensitivity of the smoke detector.
Reducing the concentration (dilution) of smoke
If there are several holes for sampling, the smoke concentration in the air sample decreases in proportion to the volume of clean air entering the pipe through the remaining holes (Fig. 8). Consider the case with 10 air intake holes. To simplify the calculation, assume that the same volume of air passes through each hole. Let us assume that smoke with a specific optical density of 2%/m enters the pipe through one air intake hole, and through the remaining 9 holes it enters fresh air. The smoke in the chimney is diluted with clean air 10 times, and its density when entering the central unit is already 0.2%/m. Thus, if the response threshold of the smoke detector in the central unit is set at 0.2%/m, then the signal from the detector will appear when the optical density of the smoke exceeds 2%/m in one of the holes. In table Figure 4 shows data for assessing the effect of smoke dilution for a different number of air intake openings in the pipe. How larger number air intake holes in the pipe, the more pronounced the effect of reducing the sensitivity of the aspiration detector is. In reality, calculating the dilution of smoke with clean air is more complicated than described above. It is necessary to take into account the size, number and location of air intake openings, the presence of corner joints, tees and capillaries in 
pipe system, diameter, etc. In addition, to equalize the air flows across the holes, and accordingly the sensitivity, a plug with a hole is installed at the end of the pipe, the area of which is several times larger than the air intake holes, which should also be taken into account in the calculation. When designing a fire alarm system using aspirating fire detectors, it is necessary to use computer program calculations for a specific type of equipment. In practice, smoke usually enters simultaneously through several adjacent openings. This is the so-called cumulative effect, which is most pronounced in high rooms. Therefore, when increasing the height of the room, it is not necessary to reduce the distance between the pipes and between the holes in the pipes. According to the British standard BS 5839-1:2001, aspirating detectors of standard sensitivity class C are allowed to protect premises up to 15 m high, high sensitivity class B detectors up to 17 m, ultra-high sensitivity class A up to 21 m. One air intake vent protects an area of horizontal projection in the form of a circle with a radius of 7.5 m.
Airflow control
It is extremely important to control the air flow through the smoke detector in the aspirating detector assembly. A decrease in air flow indicates clogging of the holes in the pipes, an increase indicates a leak in the pipe connection or mechanical damage to the pipeline. In these cases, a malfunction occurs - a decrease in sensitivity.
Monitoring changes in the level of air flow in an aspiration detector is equivalent to monitoring the condition of the loop (for open circuit and short circuit) when using point fire detectors. In addition, there is a need to store the “normal” air flow value in non-volatile memory in case of power failure. To be able to measure air flow deviations from the norm, it is necessary to ensure high stability of the aspirator performance throughout the entire service life of the aspiration detector, i.e. at least 10 years. Thus, despite the apparent simplicity of constructing an aspiration detector, it practical implementation impossible without knowledge of the laws of aerodynamics, use high technology and special computer programs.
According to the requirements of the EN54-20 standard, the aspirating detector must signal “Fault” when the air flow changes by ±20%. During the tests, the amount of air flow in the pipe is initially measured using an anemometer when air is supplied through the pipe in normal mode. After this, only an anemometer and two valves are installed in front of the block (Fig. 9). Valve 2 is set to the middle position, and with the help of valve 1 the initial air flow is set with an accuracy of ±10%. After this, valve 2 increases the air flow by 20%, and then reduces it by 20%. In both cases, the formation of the “Fault” signal is monitored.
Requirements for installation of aspirating detectors
The requirements for the installation of aspiration detectors are given in the Recommendations of the Federal State Institution VNIIPO EMERCOM of Russia. One zone, protected by one channel of an aspirating fire detector, can include up to ten isolated and adjacent rooms with a total area of no more than 1600 m2, located on one floor of the building, while, in accordance with the requirements of NPB 88-2001 *, isolated rooms must have access to common corridor, hall, lobby, etc.
The maximum height of the protected room, as well as the maximum distances in horizontal projection between the air intake opening, the wall and between adjacent openings are given in table. 5. When protecting premises free form The maximum distances between air intake openings and walls are determined based on the fact that the area protected by each air intake opening has the shape of a circle 6, 36. (Fig. 10)
conclusions
Class B aspirating detectors provide an increase in system sensitivity by more than 10 times, and class A by 40 times compared to point-type smoke detectors. Recommendations for the design of fire alarm systems using aspirating smoke fire detectors, developed by the Federal State Budgetary Institution of Fire Protection Research of the Ministry of Emergency Situations of Russia, determine ample opportunities on the protection of various types of objects with aspiration detectors.
The principle of forced air intake (aspiration) from various parts of the room for continuous monitoring has become the basis for the creation of a whole line of highly sensitive smoke detectors of the LASD (Laser Aspirating Smoke Detector) series. Effective in a room with an area of up to 2 thousand square meters, with a ceiling height of up to 21 m, with a length of air ducts from 50 to 120 m.
Each model is equipped with a system for detecting malfunctions in the functioning of the hardware and the air intake pipe system. Thanks to a simple connection to a PC or control panel, you can change standard settings using PipeIQ® software, which also allows you to design duct routing and install major equipment.
Functional features of LASD detectors
The air flow from the protected area passes through a chamber with a laser emitter capable of detecting the presence of smoke particles. The laser beam does not reflect from the walls of the chamber, which eliminates background noise and erroneous operation, and the presence of programmable states “ATTENTION”, “WARNING”, “FIRE” guarantees very early notification of changes in the composition of air masses, which in turn prevents the development critical situations(production stoppage, evacuation, material damage).
The highest level of protection of objects, especially those that do not allow the installation of classic point detectors, can be achieved due to the design and operating principle of the LASD series detectors:
Sensitivity - maximum 0.03%/m;
Log of recording critical situations - up to 18,000 events;
The impact of air flow on data reliability is minimized;
Two levels of filtration, FLU2;
Intuitive indication on the front panel;
Maintenance and installation - simple, comfortable and fast;
Minimum costs when upgrading PS systems.
The LASD System Sensor series is represented by 4 basic models with structural differences.
One laser detector in one channel, up to 1000 sq.m. controlled area;
Two laser detectors in one channel, up to 1000 sq.m. controlled area;
One laser detector in each of two channels, up to 2000 sq.m. controlled area;
Fire safety is an important aspect of human life. Each of us, while at school, at work, at home or anywhere else, must be protected from external threats, including fire. Timely detection of the source of danger can help quickly find and eliminate it, protecting more than one life, as well as minimizing material costs. Aspirating detectors - effective method ensure the safety of people and premises, protect them from fires. The features of these devices will be discussed in the article.
General information
The word "aspiration" is of Latin origin. Translated aspiro means “I inhale.” It is this word that gives an idea of general mechanism device operation. In an aspiration fire detector, it consists of sampling air masses within a certain controlled room. The extracted air is analyzed in order to detect threats and identify combustion products in a timely manner.
The main task for which experts developed such a device is to search for areas where the fire has just begun to spread and has not yet created a serious danger.
Latest technology
Aspiration detectors, according to experts, currently account for 12% of the entire market fire protection systems in Europe. Their forecasts indicate that this figure will only grow. The development of new types of aspirators makes it possible to more actively use the device, expanding the scope of its use, as well as to fully realize in practice all the advantages of such systems in a wide variety of fields of activity.
The technology that enables the detector to operate is one of the most advanced among similar devices aimed at early detection of a fire. The idea is to create a flow of air that the system absorbs directly from the controlled room, as well as its further transfer to a special optical fire sensor. Thanks to this mechanism of operation, aspiration devices can detect fires at the earliest stages of their occurrence - even before a person can feel or see smoke. The device will detect the danger even in the process of smoldering objects, heating of surfaces (evaporation of insulating substance on cables, etc.).
Principle of operation
The IPA aspiration fire detector consists of a number of pipes combined into a system where there are special openings for the intake of air masses and an aspiration device equipped with a turbine to maintain air flow.
The principle of operation of the device is quite simple, but effective. Sensors installed in the system optically monitor the received air. Considering the level of required sensitivity of the device, laser or LED detectors can be installed in it. The pipes are mounted in the room where the work will be carried out, while the aspiration device - the control unit - is placed in any other place from where it is convenient to maintain and control the system.
Application area
Today, aspiration detectors equipped with ultra-sensitive laser smoke detectors provide the most successful fire protection. Such systems are excellent for providing fire safety power plants with different principles energy production, large hangars with aircraft, automotive and other types of equipment, rooms intended for storing fuel and flammable mixtures, highly sterile production areas, hospital buildings with diagnostic equipment and other rooms with high-tech devices.
Initially, the systems were developed specifically for objects of high importance, the safety of which was a top priority. Security of material assets, large volumes Money, expensive equipment, the replacement of which can entail serious expenses, as well as stopping everything production process - the main objective aspiration detectors. In such places, it is extremely important to find and eliminate the resulting threat as early as possible, before smoldering has begun, before an open fire appears.
It is equally important to ensure the safety of premises with large crowds of people. There systems must have a particularly high level of sensitivity compared to standard devices. These can be large exhibition centers, cinemas, stadiums, entertainment and shopping centers. At objects of this kind, a preliminary signal, which only receives service staff building, makes it possible to eliminate the cause of the fire without resorting to mass evacuation, and, accordingly, panic among visitors.
Advantages
The IPA aspiration detector has a number of advantages compared to traditional systems:
- Smoke may simply not reach point-type devices installed in large rooms. Aspirator in in this case ensures the entry of air masses through all openings from any part of the room. Ventilation and air conditioners will not affect the quality of the system;
- This type of detector minimizes the effect of air stratification in a high room, where warm air located closer to the ceiling, interferes with the flow of smoke and prevents a timely response to a fire.
- Designers often face serious problems when decorating rooms where the fire safety system makes it impossible to implement one or another idea. The aspiration type of device allows you to hide all external structural elements. It is enough just to make a couple of holes under the ceiling, the diameter of which is a couple of millimeters. It is impossible to see them even with the naked eye.
conclusions
An aspiration system will help ensure the safety of valuable equipment and people at a high level.
Operational efficiency will allow you to avoid serious material costs, stoppages of the production process and human casualties, without requiring complex care or investing a lot of money to install it.
And it can be difficult to figure out what types of devices need to be installed in a particular room. Let's consider the question of what aspiration fire detectors are, their design, operating principles and areas of application.
Device
An aspirating fire detector is a device that captures combustion products (liquid or solid particles) arising from a fire and transmits a fire signal to the control panel.
The sensor is a system unit with air intake tubes extending from it, in which, at a certain distance, several holes are drilled for air intake. Inside the central unit there is an electronic receiver that analyzes incoming air samples.
Depending on the size of the controlled room, air intake tubes can be of different lengths, from several meters to several tens of meters. But in this case, additional fan adjustment is required to achieve the optimal air intake speed.
Collecting tubes can be made from different materials. Thus, in factory workshops, where the air temperature can heat up to 100 degrees, pipes made of metal alloys that are resistant to high temperatures are used. Plastic-based pipes are indispensable in facilities with non-standard ceilings where there are many bends.
Aspiration detectors are mostly designed as smoke detectors, but some models combine smoke and gas components at the same time.
According to the level of sensitivity of the devices, aspiration smoke fire detectors are divided into three types: A – high precision, Where optical medium no denser than 0.035 dB/m; B – increased accuracy from 0.035 dB/m and above; C – standard from 0.088 dB/m and more.
Principle of operation
Through a special aspirator, air is sucked into the intake pipe system. Next, it goes through a two-stage filter. At the first stage, the air sample is cleared of dust particles.
In the second filter, clean air is added so that the optical elements of the device, if there is smoke in the air sample, are not contaminated and the established calibration is not violated.
After passing through the filters, the intake air enters a measuring chamber with a laser emitter, which illuminates and analyzes it.
If the sample is “clean”, then the laser light will be straight and precise. If smoke particles are present, the laser light is scattered and recorded by a special receiving element. The receiver issues a fire signal to the monitoring or control panel.
Aspiration devices are very accurate in their operation, as they can detect a fire in initial stage, through continuous air sampling and analysis.
Installation
The main advantage of such detectors is their operation in rooms with high ceiling heights. Type A (high-precision) detectors are used in areas with a ceiling height of up to 21 meters. Device type B – up to 15 meters, C – 8 meters. This is due optimal performance devices in a certain space. Failure to follow these recommendations may result in incorrect operation of the sensors.
As mentioned above, the length of the air intake pipes can vary, up to several tens of meters. Therefore, they have several holes for air intake. They are located at a distance of 9 meters, and from the walls - 4.5 meters.
Air intake pipes do not have to be installed on the ceiling. In some special premises it simply does not exist, so the pipes can be attached to metal structures or hidden under finishing elements, leaving small holes for additional capillary tubes.
The pipeline can have several bends, thereby expanding the controlled area and reducing the likelihood of false alarms. Also, for additional protection it is possible vertical installation pipes on the walls, connected directly to the suspected location of a possible fire. This method of placing pipes is an undeniable advantage of aspiration detectors.
If there is a need for rotation when installing pipes, then the bending radius must be at least 90 mm. Turning should be avoided where possible as it slows down the air flow. There must be at least 2 straight meters of pipe per turn.
At the connection point of the pipeline with the electronic unit, the straight length of the tube should be about 500 mm, and the exhaust pipe - 200 mm.
The central unit of the device is installed either in the most controlled area or outside it, for example, in rooms with extreme conditions, where heat air, humidity, pollution.
If the device is operated in a very dusty or polluted room (woodworking shop, construction warehouse), then the external filters. It is also possible to additionally install a pipe backflow system to eliminate contaminants.
In rooms where temperature changes and condensation in the pipeline are possible, it is advisable to install additional device inside pipes to collect moisture.
The use of aspirating fire smoke detectors is possible in explosive areas. In this case, the unit is taken outside the controlled area, and installed in the air intake pipes special devices– explosion-proof barriers. They prevent hazardous gas mixtures from entering the pipeline.
Application
The wide range of sensitivity of aspirating fire detectors makes it possible to use the devices in various rooms:
IPA detector
The aspiration fire detector IPA TU4371-086-00226827-2006 is a single unit, inside of which there are five working zones: vacuum, injection and coarse cleaning, fine filtration, measurement of air samples, terminal connections. Also on the body there is an electronic fire analysis compartment:
- “temperature” – reacts to an increase in indoor temperature;
- “smoke” - sensitive to optical changes in the air environment;
- “gas” - measures and analyzes deviations from the established norm of gases in the air;
- “flow” - detects changes in gas-air flow.
On one side, the incoming air intake pipeline is connected to the device, and on the other, the exhaust pipe. A fan-aspirator is located in the vacuum compartment. Maximum length pipeline - 80 meters. The distance between the intake holes is 9 meters.
IPA is designed to protect residential and industrial premises, as well as tunnels, mines, cable ducts, etc. The device takes samples from the air, analyzes them and transmits the signals to the control panel: “Normal”, “Alarm 1”, “Alarm 2”, “Start”, “Start 30s”, “Accident”.
The sensor is operated at a temperature environment from -22 to + 55С. Does not tolerate direct sunlight on the electronic unit, as well as the presence of acids and alkalis in the air that can cause corrosion. Resistant to vibrations with frequencies from 50 to 150 Hz.