Today, no industrial enterprise or office building operates without fire-fighting equipment. And this is due not only to mandatory regulatory requirements, but also a healthy desire to save people's lives and material property. Installing a fire alarm is a crucial step, so it is important to choose the right equipment, taking into account the characteristics of the protected object, and carry out the installation according to the rules.
Fire-fighting equipment of facilities is carried out in several stages:
- project preparation;
- selection of equipment, taking into account the requirements of the facility;
- laying of cables;
- connection of fire detectors;
- setting up and starting the system.
Fire-fighting equipment is installed in any type of premises, except for staircases, bathrooms and other objects with high humidity.
A fire alarm is a chain of interconnected devices, each of which performs a specific function. The standard set consists of sensors, warning devices, a reception and control point, and an autonomous power supply. If desired, the complex includes devices for automatic fire extinguishing.
The main element of the fire alarm system is sensitive sensors. Their role is to track critical changes in the indoor climate and transmit an alarm signal to the control point. Having received a signal, the control device turns on warning devices (siren, light annunciators) or activates automatic fire extinguishing (gas or water). At the same time, an alarm signal is sent to the Ministry of Emergency Situations or the fire department.
Depending on the intended purpose, detectors are emitted that react to smoke, flame or temperature rise. When choosing sensors for a room, it is important to give preference to quality products that will not fail in a dangerous situation. By the way, a variety of models will allow you to choose devices that will organically fit into the design of the room.
Fire alarm connection: equipment selection
When choosing a fire alarm configuration, it is necessary to take into account the parameters of the room for which it is intended. Namely: area, ceiling height, fire risks, number of personnel and visitors, materials and equipment.
Such an analysis will make it possible to make the right choice in favor of one of the presented types of fire alarms:
- Threshold with radial trains. Despite the affordable price of the equipment, it requires considerable costs for installation. The operation of the threshold system is marked by periodic failures and false alarms. To increase the efficiency of the system, the number of sensors increases, but then an additional computer will have to be installed to monitor its operation. And this will also lead to an increase in the cost of the complex.
- Threshold with a modular structure. The difference between this type of alarm and the previous one is that its operation can be controlled from one point. Otherwise, it has similar disadvantages.
- Address-polling. A reliable type of equipment that is fundamentally different from the previous ones. The system consists of many detectors connected to a common unit. The control point collects operational information from sensors about the situation in the monitored sector. The main advantage of such devices is quick troubleshooting.
- Analog addressable. Up to 200 sensors are connected to the control unit simultaneously, which affects the reliability of the complex. Moreover, if one of the detectors is out of order, this will not disrupt the operation of the complex as a whole.
- Combined. Such signaling is capable of providing security at large facilities. It allows simultaneous connection of several thousand devices. One control unit is sufficient to monitor the operation. The only drawback of installing such an alarm is its high cost.
Important! The first criterion for choosing an alarm is the size of the room. For large objects, an address system is suitable, since only it can accurately determine the place of fire.
There are separate installation and operating requirements for each type of equipment. In this case, it is possible to separately highlight the rules common to the installation of all types of alarms:
- Each fire alarm has a control unit with connectors for connecting devices. In the simplest system, sensors deliver a danger signal, and the central device, in turn, turns on detectors to warn people.
- In complex models, it is permissible to integrate a security function into a fire alarm.
- It is necessary to observe the permissible distance between the cables of the fire alarm and the power supply of the object. This will avoid interference and false alarms.
- If you purchase a wireless fire fighting kit, installation will be easier.
- It is allowed to use wires only with thermal protection, and it is necessary to control their integrity along the entire length.
- The sensors are located in places where the temperature may rise, but their installation near heat sources is unacceptable.
- The detectors are mounted at a distance of 9 m from each other, but up to 4.5 m from the corners. The average distance from the device to the ceiling is 30 cm.
Before drawing up a fire alarm project, it is important to measure the room and determine the exact location of the sensors.
Note! A deposited layer of dust can affect the performance of the detector. Therefore, it is recommended to wipe it down as often as possible.
According to the legislation, the installation and adjustment of fire-fighting equipment is carried out by organizations that have received a license from the Ministry of Emergencies. In this case, an installation contract is concluded between the client and the contractor. The work is carried out on the basis of the approved project.
But to protect your own home, with the appropriate knowledge in the field of electrical engineering, it is allowed to independently install simple alarms. After setting up the equipment, a signal about the incident will be sent to the owner's phone. But he will have to call the fire department on his own.
Installation of fire alarm systems by contractors
An important requirement for the installation of fire protection systems is the involvement of contractors with a valid license or obtaining permission from regulatory authorities.
The safety of people depends on the correct installation. Therefore, when choosing a contractor, it is important to consider the following factors:
- availability of a valid license from the Ministry of Emergencies;
- the organization's presence in the SRO association;
It has always been difficult to honestly ensure your well-being, and to lose what you righteously acquired in a fire or theft is a shame, and you need to make money again ... Security and fire alarm systems (OPS) allow you to reduce the risk of loss of property from misfortune to a minimum, and insurance premium rates for housing equipped with it are essential below. Nowadays, another favorable circumstance has appeared - the installation of a fire alarm with his own hands can be done by a person who is familiar with the basics of electrical engineering and household work, and the legalization of a properly assembled system most often does not require compliance with complex formalities.
Really? OPS is a serious matter, the Ministry of Emergency Situations must respond to the alarm signal. And the installation of fire alarms, by law, must be carried out by a licensed organization, everyone knows that. Yes, but modern electronics have simplified the construction of automatic security systems (AOS) so much, at the same time increasing their functionality and reliability, that, figuratively speaking, well-fed wolves vigilantly guard the grazing herd: professionals have a stable income, focusing exclusively on security functions, and citizens ensure their safety without straining the budget.
In order to understand why do-it-yourself security and fire alarms have become quite real, and how to do it correctly, let's take a brief look at the evolution of AOS, their structure as a whole and their constituent parts, and the principles of organizing security services in residential premises.
How AOC evolved
Before chips and reed switches
Initially, AOS was built in the form of a chain of opening temperature sensors: spring contacts were soldered with Wood or Rose alloys with a melting temperature of 70-86 degrees. The chain was forcibly closed by a manual call point with normally closed contacts. All this together formed a plume Sh. The solder melted from heating, the contacts diverged, the circuit broke, the relay included in it also released with normally closed contacts, its contacts closed and turned on the alarm signal. By pressing the detector button, the alarm could be triggered manually.
Such systems at the very least worked as local, but for communication with the central console, a long line (LAN) was required, prone to malfunctions and having its own leakage resistance, wire resistance, capacitance and inductance, which could cause both false triggering and non-triggering due to actual danger ...
Therefore, on the consoles, they began to include beams - loops from the LAN - in the diagonal of the electric bridge, and in its opposite diagonal - the balanced circuit of the BC (see Fig.). The beam was no longer characterized by the resistance of the loop R W, but by the total resistance (impedance) of the subscriber Z A. By adjusting the BC, we achieved the equality of its impedance Z to the impedance of the subscriber Z A. Under this condition, the potentials in the diagonal of the bridge 1-2 turned out to be equal, and the voltage U 1 -2 = 0. When the sensor was triggered, U 1-2> 0 appeared, which triggered the alarm.
The AOC bridge scheme allowed for an important improvement: parallel to the detector, they began to include a resistor of a strictly defined value R Ш.This made it possible to judge the nature of the response by the value of U 1-2: if R Ш remained in the circuit, then it was someone who pressed the button of the detector, then U 1-2 will be about half the maximum ; this is the Attention signal. If the sensor has opened, then we will see a clear open circuit and a maximum of U 1-2; this is "Anxiety".
Such a system was not very reliable: the slightest malfunction gave a false response, the outfit left, and then the fitter, expressing his thoughts on this matter in an arbitrary form, went to look for and eliminate. False detections reduced the degree of confidence in the AOC and the object remained open from the order to the fitter. Moreover, splashes of solder sometimes fell between the open contacts, and the sensor, "beeping", calmed down again. There were cases when criminals fired at the sensors with a pneumatic gun through the window, and when they saw that the squad had left, they knew that they had at least an hour to do the "case."
BC also caused a lot of trouble: the parameters of the drug were “floating” a lot. A worker with an electrical engineering education was greeted by the police and firefighters with open arms, but often soon they had to sign a statement “on their own”: the salary was small (it doesn’t go for a knife and bullets), and the hassle was no less than that of operas.
In large facilities, consisting of many subscribers (department store, post office), the beams from the premises were directed into a local console - a control panel (SCP), which automatically gave an alarm signal via a telephone line when any of the beams was triggered. This made it possible to reduce the dependence of the BC on the state of the drugs, which were already under the control of the signalmen, but reduced reliability: having deliberately rummaged in the control panel, it was possible to disconnect the entire object from the remote control and operate there for pleasure.
At the same time, attempts were made to use the parallel connection of sensors with normally open thermo-bimetallic contacts shunted by R Ш.In theory, this would make it possible to judge from the remote control and the place of triggering by the value of U 1-2, which the sequential system does not allow in any way. However, the open bimetal turned out to be extremely unreliable: the sensor with oxidized contacts did not declare itself in advance, and then was silent, like a fish on ice, when the fire was already blazing with might and main.
Reed switches
Sealed magnetically operated contacts - reed switches - made the first revolution in AOC and OPS. Reed switches can withstand billions of operations without oxidizing the contact surfaces, and the problem of temperature triggering was easily solved by using holding magnets made of materials with a Curie point of 70 degrees: when heated, the magnet stopped magnetising, and the contacts opened.
The principle of the reed switch device allows you to make it switchable, which gives a reliable sensor suitable for both serial and parallel OPS. True, the accuracy of determining the location of triggering by analog methods remained low, therefore, parallel analog OPSs did not gain popularity. Nevertheless, it was thanks to the reed switches that the fire alarm appeared in the apartment: the reliability and cheapness of the sensors ensured the cost of the system, available even to an ordinary Soviet consumer.
The first smoke detectors also belong to the "reed era", but by no means household ones: smoke triggering was provided by ionization of the gap between fixed contacts, for which it was illuminated by an ampoule with a radioactive isotope. Alarm fitters were afraid of such sensors, in a thick steel case and marked with a radiation hazard sign, like fire, and they were rarely used, at especially important facilities.
At the same time, the control panel began to transform: the use of microcircuits of a medium degree of integration and analog-to-digital converters (ADC) made it possible to simplify the BC or completely abandon them and measure the beam parameters directly. The first self-powered wireless control panels appeared, which, regardless of telephone lines, gave an alarm to the remote control using the Altai system, the prototype of modern mobile communications invented in the USSR back in the 50s.
Chips and lasers
Large integrated circuits (LSI, chips) and miniature semiconductor lasers made a real revolution in the OPS and made it widely available. This affected all the links of the OPS, and the best of the previous achievements organically fit into the new system (see the figure earlier in the text below).
Sensors with the help of laser detectors control the temperature and smoke content at once according to several parameters, which eliminates false alarms (see the figure on the left). Some sensors combine the functions of motion detectors, they will be discussed below. "Smart" sensors can also be autonomous, equipped with a built-in battery.
Today's control panel is a computerized device capable of working both with “smart” junior colleagues and with old, but absolutely reliable and very cheap reed switches. This made it possible to include in the composition of the household OPS SPU - a signaling and triggering device, at the signal of the control panel or directly from the sensor, including display boards, flashers, sirens and opening the valves of the automatic fire extinguishing system.
Modern FSA are digital-to-analogue parallel-address: each sensor has its e-mail address stitched, and the control panel knows exactly where what happened. Analog sensors with the help of developed software are also quite accurately controlled by the parameters of the loop. The alarm signal is sent via GSM to the owner's mobile phone and to the computer of the security organization. The alarm can be duplicated directly from the chip sensor, and the activation of the SPU - in addition to it from the checkpoint.
Motion sensors based on the same chips and infrared lasers made the fire alarm system really security: they control the entire volume of the room or the area of the yard. The laser scanner signal is converted into a code, and the control panel processor continuously compares the codes one by one, filtering out interference from weather, precipitation, small safe objects.
The capabilities of a modern fully functional FSA are shown in the figure. This is very expensive, but the system is simpler, quite reliable for an apartment, you can assemble it yourself. How - will be described below, but for now let's see what is needed and what can be achieved in general:
- An uninterruptible power supply (UPS) is necessary for the fire alarm to continue to operate in a de-energized apartment;
- Universal detectors-annunciators: on the left is a group of autonomous ones, for example. in the garage;
- Motion sensors;
- Electronic lock;
- Burglar-proof reed contactor;
- Index board;
- Local alarm signaling device;
- Display with control panel;
- OPS automatic machine.
Let's give some explanations. Firstly, reed-switch opening sensors are still holding in their place, not competing with motion sensors, and it's not just about cheapness and reliability. The small reed contactor is easy to hide, its operation is not detected by the anti-scanner. The search for such a "bug" (and it is not known whether there is one at all) with a skillful installation takes so much time that hacking loses its meaning.
Secondly, instead of any of the devices according to pos. 7, 8 can be connected SPU. Thirdly, according to pos. 10: the FSA must be powered from a separate machine turned on BEFORE the apartment one, otherwise the reliable operation of the system is not guaranteed. And, finally, a remote control with a display by an access code allows you to independently reset, test and reconfigure the OPS.
Organizational structure
The radical improvement of the technical base also led to the improvement of the organizational structure of the FSA: subscribers rarely enter the Emergency Situations Ministry control panel, it is expensive and overloads both equipment and personnel. The role of the signal concentrator was taken over by private security firms. They do not light up or sneak everywhere and not always, and they can get a lot of subscribers with an acceptable load, which, with a small monthly fee, provides a decent income.
For the owners, such a system is also beneficial: a private licensed security guard will willingly advise, help with advice, he does not take experience in interacting with the Ministry of Emergencies and the police. And since the owner still pays him his hard-earned money, then it is easier to demand if something happens than from the state structure.
We take on the signaling
Do you need a project?
A fire alarm project is needed, and not so much for formal reasons. Only a security guard with extensive experience will be able to accurately indicate the location of the devices, their types and connection diagram. Otherwise, the flame can rage to the point of irreparable, and the attacker, immediately spotting the "samopal" (they are well versed in signaling), will only chuckle and, "bombing the hut", will sit down at ease in the owner's favorite chair, drinking the owner's brandy, smoking the owner's cigar, gently stroking it on her knees, tightly packed with the master's goods and glancing ironically at the sensors in full combat readiness.
However, security firms, generally rightly believing that the main thing is real security, and not paper, often go to indulgences to potential subscribers: they agree to make a project cheaper, sketch, or limit themselves to even cheaper advice: where to install which sensors, where to place the control panel, what cable and how to connect everything.
Then, after checking the work, they take it on guard, and according to the documents they carry it out from themselves retroactively. This is no worse for the owner: once the contract is signed and the apartment is already on the control panel, the whole measure of responsibility falls on the guards. The components of a modern fire alarm system are completely reliable, maintenance of a fire alarm is reduced to a periodic check of its operability and readiness, which, together with the security officer on duty, may well be carried out by the owner himself, so that, as a rule, there are no problems with service.
How to do what?
The law does not prohibit making an OPS yourself, only they will not take such a remote control. We'll have to confine ourselves to displaying the alarm on a mobile, but this is already a serious help in misfortune: the Ministry of Emergency Situations and the police are obliged to respond to any signals from citizens. Therefore, we will describe which equipment to choose for which case, and how to properly assemble it into a workable whole.
PKP
The types of modern control panels are shown in the figure. First from left is professional multi-beam analog-to-digital. These can work with any FSA schemes, be connected in cascade, ensuring the protection of objects of any complexity and conduct a dialogue with the computer of the security organization, recording and transmitting a complete picture of the development of the situation. They are not used in everyday life.
The next one is semi-pro, digital for parallel addressable FSA. It is shown open because outside it is a blank box. At the bottom right in it - IP; next to it is a battery, quite powerful, as you can see, for several hours, up to a day, autonomous operation.
On the top left is an electronic unit, and in an empty space near it in a round-the-clock guarded premises there is a control panel, but usually it is taken further away. The fact is that such a heart of an OPS, although it is equipped with a self-defense system, is still the most vulnerable point of the security system. The work of the processor can be detected by a special scanner, like the way car thieves do, and intervene in an undesirable way for the owner.
Therefore, it is strongly recommended to locate the control panel in a hidden, hard-to-reach and sufficiently well-electrically shielded place, for example, in a reinforced concrete basement. As for the RS482 serial interface, which connects the control panel and the keypad, its signals are very well coded, and it is impossible to break through it to the processor.
Semi-professional control panels in everyday life are used in elite estates individually or collectively in residential complexes: one such control panel allows connecting up to 255 sensors to it.
The next one is a multi-beam household control panel. This is an already affordable device for the average citizen. Such a device is intended for private households with outbuildings: in addition to servicing reed and chip wire beams, it can process signals from 2-8, depending on the model, wireless sensors.
The far right is the simplest apartment control panel. The cheapest models are served by only one beam (no more is needed in the apartment), but, like all of the above, they can transmit a signal to a mobile number. A number in inexpensive household control panels without access by code from your remote control is flashed upon purchase or from a security company, so you need to keep your phone with you charged and with an account that is not empty: mobile operators charge a fee for receiving messages via GSM.
Household control panels must be completed with detailed instructions with typical fire alarm schemes, a list of types and models of sensors compatible with the device and recommendations for installing the system. Often the set includes a flasher for the front door and a sticker "Protected object". These are very useful additions: their presence most often makes villains and vandals go home.
The control panel must comply with the European standard EN54, which is ensured by the ITPB, LPCB or VdS certificates.
Sensors
Sensors and their connecting wires are the key node of the fire alarm, which determines its reliability as a whole. First of all - about the wires. The sensors are no longer connected with telephone noodles, fragile and unreliable: there are many types of signal two- and multi-core cables in a round outer sheath on sale, which can be laid along the walls so as not to be conspicuous, and hidden under decorative sheathing. But the actual sensors should be discussed in more detail.
Choice
For an apartment, the best option is good old reed "caps", see fig. In the kitchen, a chip is desirable, reacting, in addition to heat, and smoke. If significant valuables are stored in the apartment, then it is better to put fully functional valuables near their locations with motion detectors.
In a private house, a motion sensor in the courtyard with a built-in SPU loaded onto a lighting lantern will be useful. And uninvited guests will be scared away, and you yourself will not have to stumble in the dark: the SPU will illuminate.
Multifunctional sensors are necessarily equipped with an indicator LED, and the simplest ones can be with or without it. The former are preferable: the glow or vice versa, the extinguishing of the indicator indicates a sensor malfunction. If a false alarm occurs, you do not need to climb the ceiling with a tester - a bad sensor is immediately visible.
Accommodation
At first glance, the norms for the placement of fire alarm sensors are very liberal, see fig: no further than 4.5 m from a wall or corner and no more than 9 m between the sensors. But this was done only for the sake of convenience of configuring a specific fire alarm, but in fact, the location of the sensors is a delicate matter.
Firstly, when placing them on the walls, the ceiling must be at least 0.2 m, otherwise the sensor may end up in the smoke pocket and give a false alarm. Have you seen smoky rooms? There, after all, the upper corners are most smoked. Secondly, with beams on the ceiling, the sensors should be placed on their lower surfaces, and not on the side or in the space between the beams, for the same reason.
And finally, the sensor does not cover the entire hemisphere, and its sensitivity depends on the distance to the source of danger. The controlled area in the form of a circle in an empty room depends on the height of the ceiling as follows:
- Up to 3.5 m - up to 85 sq. m.
- 3.5-6 m - up to 70 sq. m.
- 6-10 m - up to 65 sq. m.
- From 10 m - up to 55 sq. m.
By the flame:
- Up to 3.5 m - up to 25 sq. m.
- 3.5-6 m - up to 20 sq. m.
- 6-9 m - up to 15 sq. m.
- More than 9 m - not controlled; a fire will turn into a fire before the sensor is triggered.
"Before" in front of the square means that this is the maximum achievable value - in an empty room with 3/4 proportions. An accurate calculation of the location of sensors in habitable rooms requires computer modeling or the eyes of an experienced specialist. If the FSA is done independently without outputting to the security console, then we can assume that one sensor in the living room "sees" a square below with a side L equal to the ceiling height up to 4 m. - at a distance L from each other. In long and narrow rooms, it is primarily the distance between the sensors that comes into play.
Example: corridor in Khrushchev 1.75x4 m; ceiling height - 2.5 m. Two sensors are required, located 1.75 / 2 = 0.875 from the end walls. In the bedroom of the same Khrushchev 2.5x4.5 m, two sensors are also needed 1.25 m from the end walls.
Connection
Fire alarm sensors are connected strictly according to the instructions for them. The beam loop always ends with a terminating resistor R. Its value is indicated in the control panel manual. Default R = 470 ohms, but 680 ohms or 910 ohms may be required. Let us explain in more detail only two frequently requested points.
First- inclusion of five-terminal sensors IP-212, which have proven themselves well, into a two-wire loop. How to do this is shown in the figure on the left.
Second- connection of conventional sensors with one terminal block. The cable wires must enter / exit the terminal block MIRRORLY, as shown in fig. on right.
Third- sensors with two terminal blocks. The left block - FOR A LINE, which is connected according to the instructions or as described. But with the right one should be dealt with already when buying: it is intended for autonomous activation of the SPU; some of the most common sensor layouts are shown in the last figure.
If the contacts of the loop (terminals 1-4) and SPU (terminals 6-8) are electrically separated, as in the extreme right position, then you need to find out the permissible voltages and current or power of the SPU. If the contact is common, as in the other three positions, then the voltage is 12 V at a current of up to 200 mA, and it will go to the SPU from the loop, i.e. load the sensor with bulbs, bells, etc. not possible - the control panel will break down.
The basis of the set of technical means used to alert about a fire or illegal entry into an object is made up of special sensors or detectors located in all rooms. The installation of a security and fire alarm has only one goal - to protect a person in the course of his work activities, wherever he is at a given moment in time.
In order for such equipment to work normally, you need to adhere to strict rules regarding the order of its design, subsequent installation, current operation and maintenance.
Principle of operation
A modern security and fire alarm system (FSA) installed at the facility is a technical complex consisting of a whole set of special devices. Their main purpose is to provide conditions for early warning of danger.
Thanks to these devices, in most cases, it is possible to secure the premises, as well as to protect from fire not only the buildings themselves, but also the material values stored in them.
The fire and burglar alarm complex consists of two interconnected parts. The first part is a set of sensors mounted directly indoors or outdoors. They can react to temperature, smoke, movement, broken glass, and carbon monoxide emissions.
The second mandatory part of the security and fire alarm system is the executive (dispatching) one, designed to collect and register information received from the sensors.
On the dispatcher's console there are indicators that signal the state of the sensors placed on the objects, which allows you to receive a signal about a fire or unauthorized entry on the plan of a specific room.
In the semi-automatic security mode, after receiving an alarm message at the console, the operator manually turns on the notification system, activating the voice and visual channels of information transmission.
After confirming the danger of fire, the alarm signal is transmitted to the access control system, which transfers all structures of this organization to the evacuation mode. The same signal is sent to the addresses of engineering networks, carrying out their temporary blocking.
Functions
In automatic mode, a professionally mounted fire and burglar alarm FSA is capable of performing the following functions:
- determination of the exact location of the fire;
- identification of the lesion after duplicating the initial signal;
- identification of damage in the network caused by a short circuit or a break in the loop (with reference to the layout of the facility);
- detection of the place of fire at its very initial stage;
- control of the blocks for processing the received information with the output of the results to the dispatching console.
With the help of security and fire alarms, it is possible to monitor the state of objects on plans of varying degrees of detail. Information is displayed on the remote control not only in text, but also in graphic format.
Project preparation and calculation
The design of integrated security and fire alarm systems is the first stage of installation and involves the implementation of a whole range of technical measures. The efficiency of the fire and security parts of the alarm system depends on their quality.
Only professionals should be engaged in the development of the project, capable of making complex calculations of the operating modes of a large group of fire and security devices, taking into account their specific location.
Since the individual components of the security and fire alarm system (sensors and the dispatching console) are combined by means of a loop, the main attention in the design is paid to the marking of the route of its laying.
During the installation process, additional protection of cables and wires should be provided, which, according to the project, should be laid in pipes (or in a special protective corrugation).
When developing a technical one, the design features of this object should also be taken into account, according to the elements of which connecting lines (loop) are usually installed. To do this, you should carefully study the layout of the facility and prepare an expert assessment containing the following mandatory sections:
- the level of complexity of the design;
- the size of office space and rooms;
- features of the layout.
When designing a security and fire system, special attention should be paid to areas of increased fire hazard, which are highlighted in a special way in the general plan.
The preparation of design documentation for the installation of a security and fire alarm system includes the preparation of a technical assignment, taking into account the customer's requirements.
The layout and design features of a building or object are studied. An estimate is being prepared, confirmed by special calculations. Particularly important aspects of design work are coordinated with the customer, after which the final signing of the prepared documents takes place.
Before starting the installation work, appropriate calculations are made, allowing you to choose the optimal system architecture, for the installation of which you will need a minimum of costs. Taking these factors into account significantly affects the final cost of a set of security fire-fighting equipment.
A well-calculated system should manage with a minimum number of sensors and detectors, determined taking into account the height of the room, and also have an optimal length of the connecting loop.
It is also necessary to clarify the required cross-section of the signal conductors and determine the capacity of an independent power source (battery).
Installation and connection
Installation and connection of security and fire alarm equipment at the protected facility is carried out in compliance with the following rules and regulations.
The number of fire and security detectors obtained on the basis of the calculation must be evenly distributed over the surface of the ceiling.
In accordance with the requirements of the standards, at a room height of more than 3.5 meters and an area of about 80 square meters, at least two fire detectors must be installed.
During installation, it is necessary to ensure that they are not located close to the ceiling surface, but are fixed with a small gap specified in the instructions.
During the installation process, it is necessary to focus on the pre-designated points at which the devices are first carefully fixed, and then connected via a two-wire line to the power source (battery) and the remote control.
They are all connected in series with each other (that is, by a loop), and the limiting resistor is mounted in the block of the last device in the chain.
At the end of the installation work, it is necessary to check the loop for operability, for which a lighted match is brought to one of the sensors and the operation of the corresponding indicator on the dispatching console is recorded.
If any deviations in the operation of the alarm are detected, it is necessary to configure it according to the instructions.
Locations of fire detectors
According to the requirements of regulatory enactments, the locations of the detectors of the security and fire alarm systems are selected as follows.
The distance from the installation site of the sensors to the wall should not be less than 4.5 meters with a gap of about 9 meters between them. These standards are valid for single-level ceilings up to 3.5 meters.
In cases where alarm sensors are mounted on walls, the distance between them should be within 0.2 meters, which is quite enough to eliminate false alarms due to accidental smoke.
How the warning system works
In the event of a fire, the detectors instantly react to heat or smoke and automatically transmit a signal to the remote control that initiates a sound notification.
The security unit acts in a similar way, registering the fact of burglary, entry into the room, and giving an alarm. Such an alarm, in terms of its structure and method of informing about a fire, is local and centralized.
Local or autonomous devices are part of an independent fire and burglary registration unit with built-in storage and conversion modules for information received from the sensor.
When using them, the presence of a central dispatching console with a set of sound and light warning devices is not provided.
Centralized systems operate in both semi-automatic and automatic modes and provide for the generation of alerts and their distribution to pre-designated zones.
To implement the notification function in centralized security and fire alarm systems, special input and output interfaces are used, which provide information output in an easy-to-understand form.
Possible malfunctions
Installation and repair of security and fire alarm systems are carried out by specially trained personnel who are able not only to competently organize the installation, but also to restore operability in the event of a malfunction.
In order to avoid bringing the alarm to the need for major repairs during its maintenance, preventive work is regularly carried out, consisting in cleaning the smoke detectors from dust and small particles of debris.
During a control examination of a damaged system, there are frequent cases of detecting a loop break or an accidental error made during installation.
During their operation, the following problems are encountered:
- damage or breakage of the loop;
- systemic power outages;
- malfunctions in the electrical circuit of the dispatching console;
- discharge of auxiliary power supplies (batteries).
Maintenance of security and fire systems is mandatory as part of preventive measures carried out at the facility. Only if this requirement is met, it is possible to extend the period of trouble-free operation of security equipment.
Before installing a fire alarm, you need to understand the types of such systems and choose exactly the type that suits your specific requirements. You can install the system yourself, but it is better to call a special team. If desired, the owner of the system can register it with the State Fire Inspection.
Types of systems
All types of fire alarm systems can be divided into several types.
- Threshold systems with radial stubs.
- Threshold systems with a modular structure.
- Combined system.
Threshold systems with radial stubs
Threshold systems equipped with radial stubs are popular for one single reason - they are very cheap. Moreover, the installation of such equipment will be quite expensive. Such a system has a lot of disadvantages that are difficult to notice right after installation.
In particular, the control panel can give false signals. The number of such false notifications here is an order of magnitude higher than in any other devices. At least about two detectors should be installed in one room, and this leads to increased costs. Although the equipment is very economical, the installation and the expense of extra detectors will add up to a significant total cost.
With an abundance of sensors, it will be impossible to track them from one computer.
Also, the control panel has a certain threshold at which the signal is generated. The serviceability of the alarm is almost impossible to check; if it breaks down, the sound may not be heard. PEP is highly human factor.
In short, the disadvantages of such a system are much more than advantages. When installing an alarm for serious purposes, it is best to choose something else.
Threshold systems with a modular structure
Such systems are inexpensive, like the previous type of alarms. They have practically the same disadvantages: expensive installation, a certain threshold for signal supply, dependence on the human factor.
However, this type of alarm can be freely controlled from a single console or computer. In addition, two units can be installed at the same time here.
Such a system has a fundamentally different structure than the previous two. It works differently. All sensors in it are combined into a common unit, while they are regularly checked from the control panel. The signals from the sensors can have four responses: "normal", "fire", "malfunction", "absence".
The disadvantage of this type of alarms is that they detect the source of fire too late and report it. Otherwise it is a very good system.
This system has an optimal ratio of price and quality, with the help of the questionnaire panel you can always identify a fault in the sensors in time, as well as get a lot of useful information.
Up to two hundred sensors can be connected to one loop of such an alarm. To appreciate all the advantages of this system, you need to understand how this type of fire alarm works. It assumes the presence of twisted pairs, this is its main advantage and at the same time a disadvantage. When you exit a standing sensor, the system itself remains fully operational.
The sensors do not have any specific alarm threshold. They simply register the atmosphere at their assigned point and send the data to the control panel. This allows you to very quickly identify the source of fire. In addition, such a device of the system allows you to find out about all the faults in the network in time.
The cost of the installation of an analogue address system itself will be inexpensive, but the equipment will cost decently. Probably the only drawback of this signaling is that the protocol requires the mandatory presence of a twisted pair.
Combined systems
Combined fire alarms are the most powerful. They allow the installation of several thousand sensors and devices. They have a very wide range of additional equipment.
Fire alarm systems and devices of this type are controlled from a single control point, which greatly facilitates security monitoring. There are practically no drawbacks to a combined fire alarm, except that it can cost a decent amount.
Installation and dismantling
Alarm installation requires compliance with special rules that are prescribed in the regulatory documentation. It is advisable to install such systems with the help of professionals if the owner of the premises does not have the skills to work with such systems.
Some owners ask the question whether it is possible to create a fire alarm with your own hands, that is, to assemble the device itself at home. Yes, this is quite possible, but within certain limits. You cannot create complex systems on your own. The master can only make the simplest devices, and no one can guarantee that they will function properly.
Sometimes the fire system will fire without any ignition. Frightened owners do not know how to turn off the fire alarm. The sound of this system is very specific and hardly anyone will like it. To restore peace and order, you need to do the following.
- First you need to find out the reason why the alarm was triggered. There may have been smoke or a small fire. We must immediately ventilate the room.
- If, nevertheless, the system worked for no reason, then you need to decide on its type. The simplest alarm with sensors can be disabled simply. To do this, it is enough just to remove the power supply from the sensors themselves. With a more complex alarm device, you need to go to the control panel. The system often turns off only after the appropriate code has been entered.
- A radical way to eliminate noise is to bite the alarm wires. If you need to restore it, you will have to carry out a number of works.
A properly installed fire alarm is a guarantee of the safety of your property and your own safety. There are several effective systems on the modern market that work according to different principles. Explore the specifics of the options available, select the type of fire alarm that best suits your needs, and then refer to the manual for calculating and installing sensors and dealing with false alarms.
There are systems that work with smoke and heat detectors... The principle of operation of the devices is clear from their name: heat sensors are triggered when the temperature rises, while smoke sensors are activated when smoke is formed in the range. The sensors can be powered directly from special control devices or batteries.
Suitable for home analog addressable system, and address-polling signaling... As quickly as possible, the fire is found by the setting of the address-polling type. A modern analogue addressable alarm system is able to determine the place of ignition and even take some actions, for example, turn off the ventilation system, close or open all the doors in the house, turn on the sound alarm, etc.
Modern fire alarms with built-in GSM transmitter... In the event of a fire, such a system will call or send an alarm message to the specified number. This will give the owner the opportunity to immediately call the fire department and come home in person. Modern GSM-systems can be programmed to alert several telephone numbers at once, which is very convenient.
The nuances of installing and maintaining a fire alarm system
Fire detectors should be installed on every floor and in every room of the house. Attic and basements are no exception. The best place to place fire detectors is in the ceiling.
You can do the installation of sensors yourself, but if possible, it is better to entrust this work to a licensed company.
Once installed, the alarm system will need regular maintenance. If the sensors are powered by batteries, check that the controllers are working every month. The batteries themselves usually consume their resource in a year. It is recommended to replace the sensors with new ones at least every 7-10 years.
If the system elements are powered by a lithium battery, the sensors should also be tested monthly. If it is necessary to replace the battery with a new one, replace all warning devices at the same time.
If your apartment or house has a wired system, check it every month. The power supply must be changed annually. The service life of the entire system is on average 7-10 years.
When installing the fire protection system, pay special attention to the cross-section and layout of the cables. Consider the fact that in the future you may want to redevelop rooms or make basic repairs. Try to think over everything so that any repairs can be carried out without changing the configuration of the alarm system.
Provide reliable protection of the system from all kinds of unacceptable external damage (insects, chemicals, etc.). The norms and rules for the installation of the systems in question are dictated by the corresponding GOSTs. Carefully study the current regulatory documents before starting installation work.
Buy equipment only from trusted and licensed suppliers. Doubtful production alarms usually behave unpredictably. For example, they often work without any hint of fire, and in a real fire they are stubbornly silent. Therefore, do not skimp on your own safety and buy a quality system from a reputable manufacturer. All the same, the replacement of the alarm will not have to be carried out very often.
After installation, put your alarm for service. To do this, it is better to contact a specialized company.
In the process of preparing for the installation of a fire alarm, a number of special calculations must be performed. They will help you choose the most optimal system option and avoid unnecessary costs during the installation and maintenance of sensors.
One of the most important steps in calculating an alarm is determining a suitable power supply capacity... Decide which power source is the most convenient for you to connect the sensors. There are a lot of such sources: from ordinary batteries to solar accumulators.
The required battery capacity is indicated in the instructions for the alarm. Compare the value found with the information on the battery case. If the battery capacity is not enough, buy a more powerful battery or connect several batteries in parallel.
When connecting multiple batteries in parallel, make sure their voltage is the same. Otherwise, the total capacity of the battery circuit will decrease.
Specify the required cross-section of wires for connecting fire alarm sensors... This information is usually provided in the instructions for the system. Also pay attention to metrics such as standby and alarm battery capacity. Add these numbers together and you get an indication of the total battery capacity required for your specific system.
Alarm connection using typical sensors as an example
First step . Determine the required number of alarm sensors. To determine the number of controllers required, you need to know the area of the room to be serviced and the height of the ceiling. The current regulatory documentation says that if the ceiling has a height of no more than 350 cm, then one sensor is enough to service 80 m2. At the same time, fire safety regulations require that even in the smallest room there should be at least two controllers. Follow the last rule.
Second phase. Mark the locations for the fire detectors. The maximum permissible distance from the wall to the sensor according to the regulatory documents is 450 cm.The sensors must be installed in increments of at least 900 cm.This rule is relevant for those situations when the ceiling is one-level and its height does not exceed 350 cm.
Wall-mounted models of fire detectors should be placed 200 mm from the ceiling surface.
Stage three. Fix the sensors in the marked places and connect them to the power supply using two-wire wires. The sensors are connected in series with each other. A resistor must be installed in the block of the last controller.
Stage four. Test each sensor after connecting. To do this, light a candle and move it with the flame near the detector.
If the fire alarm went off without any hint of fire, you need to follow a few simple steps to turn it off. Otherwise, loud sound alerts and unnecessary additional funds triggering will cause you a lot of trouble.
First option. Find out why the alarm went off at all. The system must not be turned off without first checking all serviced premises. High-quality systems rarely work for no reason. Maybe in some room of the house there was smoke or a real fire. If there is an “irritant”, eliminate it, and the system will shut down on its own. Be sure to check the condition of the wiring.
Second option. If you do not find any reasons for the alarm to be triggered, proceed to disabling it. The shutdown procedure depends on the type of specific system. The simplest option is to turn off the alarm from the power source. However, this option can only be considered as a temporary solution to the problem, because With the alarm turned off, you endanger the safety of your home and everyone in it.
The third option. If your home has a centralized control panel, turn off the alarm from it. In some situations, this procedure requires you to enter a special code. If you do not know it, contact your fire alarm company.
The fourth option. If the controller is very dusty, for example, during repair work, to disconnect it will be enough to remove the front panel from the sensor and rub its “insides” with a cotton swab slightly moistened with alcohol. If this was the problem, after such cleaning, the alarm will turn off. From now on, monitor the condition of the sensors and promptly clean them.
Fifth option. If you need to turn off the fire alarm in a separate room, you can wrap the detector with adhesive tape. However, after such processing, the controller will become useless. Remove the tape immediately after identifying and fixing the problem.
Sixth option. If none of the above helps, use the most radical solution - cut the wires connected to the sensor. The fire alarm will turn off but will be completely useless until you repair it. Try as soon as possible to deal with the cause of the false triggering of the sensors and eliminate the malfunctions.
If possible, contact a specialized company. Its employees will diagnose the fire alarm and give recommendations on further actions on your part.
Thus, there is absolutely nothing complicated in self-installation of a fire alarm. You just need to understand in detail the connection sequence of the sensors and follow the instructions. Be sure to check the manufacturer's recommendations. Many modern systems have a number of features that need to be clarified separately. Your safety depends on the correct installation and connection of the sensors, remember this.
Happy work!
Video - Do-it-yourself fire alarm installation