Fire alarm loop. Security alarm loop What is shs in a fire alarm

V.N. Korenev,
Ph.D., Head of Development
and implementation of Security Systems LLC,
Novosibirsk

Threshold signaling loops, despite their low information content and susceptibility to interference, continue to be used in various systems alarm system. This is due to the fact that there are still many non-addressable detectors and sensors on the alarm product market that have two stable states at their output, corresponding to normal and alarm. They successfully compete with addressable products due to their low cost and compatibility with various control and control devices.

Despite the simplicity of the circuitry, threshold alarm loops can be made much more informative than is implemented in existing equipment. This becomes possible with the use of modern microprocessor technology, which increases the ADC bit capacity, data processing performance, and the amount of built-in memory, and at the same time reduces the price.

However, an increase in information content is associated with an increase in controlled events and the complexity of algorithms for transition from one state to another. It is becoming increasingly difficult to describe these processes. Therefore, when developing such products and describing them for users, it is convenient to use physical and software models of the alarm loop.

Each threshold alarm loop (LS) of the device can be described by models from two points of view:

From a physical point of view- This electrical circuit, connecting the device with detectors (sensors) through wire connections (Fig. 1). Each AL has various circuit design options selected by the developer. The connection diagram shows the detector contacts, resistors and other components that ensure the operation of the alarm loop.

Any detector can be represented as an electrical contact, which, when triggered, abruptly changes its resistance: it becomes either closed (contact resistance is zero) or open (contact resistance is infinity).

The detector contacts are connected by wire connecting lines to the terminals of the control panel.

In the control panel, the terminals are connected to a “Resistance Meter”, which measures electrical resistance the entire AL circuit, and the “Decision Device”, based on the value of its resistance, makes a decision about whether the detector has worked or not.

Fig.1. Threshold alarm loop model

The AL is connected to the resistance meter through the terminals located on the board of the control panel (RCD). The meter measures the electrical resistance of the entire AL circuit, and the deciding device, based on the value of its resistance, decides whether the detector has worked or not.

From an information point of view is a software object consisting of a fixed set of events. An event in the loop can occur as a result of a change in the loop resistance, or come from outside, in the form of control commands. The set of events is determined SHS tactics. Each SHS tactic includes:

Type of alarm loop (fire, security, emergency and control) and name;
Electrical connection diagram;
Scale of AL resistance ranges, divided by thresholds;
Linking states to AL resistance ranges;
List of AL events;
Matrix of events.

As an example of the use of terms, consider the “Single-threshold” fire alarm loop tactics. This tactic provides for the issuance of a “Fire” signal when any one or more detectors are triggered:

Alarm loop type – fireman, single-threshold .
Electrical circuit diagram - can be performed in several versions (Fig. 1.1.):

with normally closed contacts of detectors (K1, K2). In this case, the contacts are connected in a loop line in series, and the control resistors are connected in parallel with the contacts of the detectors;
with normally open contacts of the detector (K3, K4). In this case, the contacts of the detectors are connected in parallel to the loop line, and the control resistors are connected in series with the contacts;

Fig.2. Electrical diagrams switching on fire detector contacts.

3) Resistance range scale, divided by the developer by resistance thresholds into 8 ranges: D1 ... D8 (Fig. 3).

Fig.3. ShS resistance range scale

When the contacts of the detectors are closed and opened in various combinations, the resistance of the loop falls into one or another range.

Linking states to AL resistance ranges

Loop states are understood as physical or logical properties that characterize a loop when its resistance changes.

In the “Single-threshold” ShPS, the developer assigned the following states:

Norm;
Fire;
Break.

These states are assigned to ranges:

List of AL Events

An event is a transition from one state to another. In this case, both the states of the loop itself and other states of the device related to the loop are taken into account.

In the “Single-threshold” ShPS, the developer has assigned the following events:

Reset- an event in the device at the time of its reboot (power on);
Not Ready- an event meaning that after a reboot the loop resistance is not in the “Normal” range;
On Duty– the resistance of the loop has moved into the “Normal” range [D5];
Fire– loop resistance in any of the “Fire” ranges [D2] [D3] [D4] [D6] [D7];
Closure- loop resistance is in the “short circuit” range [D1];
Break- loop resistance is in the “Open” range [D8];

Event Matrix

The event matrix determines the sequence of events when states change. Using a matrix it is convenient to represent the loop operation algorithms. The matrix is a table that contains the following elements:

Fig.4. Appearance event matrices.

The principle of using the matrix to describe the loop operation algorithm is presented in Fig. 5. As an example, in the far left column, let’s select the current status as “On Duty”. Let's highlight the line with events in the field of events that are possible while in this status with a green background. Next, let’s look at what event will happen when a new “Fire” loop state appears:

Fig.5. An example of how the matrix works when the “Fire” condition occurs

As a result of the matrix’s operation, the plume switched to a new current status of “Fire”. Analysis of the influence of new loop states in the “Fire” status shows that no other physical change in the loop resistance will change this status. In order to remove a loop from the “Fire” status, it must be transferred to a new “Reset” state. This state can come to the loop from the outside: for example, when the reset button is pressed.

Thus, the matrix representation greatly facilitates the description complex algorithms operation of threshold alarm loops and can be used both in their development and in describing the operation of the product in the user manual. Obviously, the matrix representation is also convenient when describing the algorithms of other components of alarm products.

Literature:

Pinaev A., Nikolsky M. Assessment of the quality and reliability of non-addressable devices fire alarm//Journal "Security Algorithm", No. 6, 2007.
Neplohov I.G. Analysis of the parameters of a two-threshold PPKP loop // Safety Algorithms No. 5, 2010.
Control device dangerous situations and alerts "Guardian-IT"//

Let's figure out what an alarm loop (AL) is and how to organize it correctly. Let's start with the fact that a security loop is a connecting line (electrical circuit) connecting various alarm sensors (DS) or detectors - in the context of this article these are synonyms.

In addition, the loop contains a terminal device (TD), which coordinates it with the control panel (RCD).

The terminal device can be:

resistors;
capacitors;
diodes.

What exactly is installed at the end of the loop depends on the specific control panel model. It is worth noting that in systems burglar alarm resistors are most often used, so we will focus on this option. The structural diagram of the loop is shown in Figure 1.

I drew everything at once possible types sensors, we will now consider their operation, but in a real situation, as a rule, one connection option and detectors with the same tactics for generating an alarm notification are used.

Combinations are also possible various connections, but they are quite rare. Now let's move on to consider the main types of loops and the principle of their operation.

Attention! The numbering of loop types in this article is arbitrary. Moreover, each manufacturer can put its own interpretation into the concept of AL type. Be sure to keep this in mind!

TYPES OF SIGNALING LINES

1. AL with sensors that operate “to open”.

A very common option in security alarms. When the detector is triggered, the electrical circuit is broken and the current in the loop drops to zero. The same thing will happen if there is no power to the detector. But if the sensor malfunctions, there are two options:

the contacts will open;
will remain closed even if an intruder is detected.

In the first case, everything is clear and simple - the device will work and the malfunction will thus make itself known. The second option is dangerous because it can only be detected by fully checking the functionality of the sensor, which no one does every day. The only consolation is that such cases are rare, but, nevertheless, they do happen.

2. AL with a sensor that operates on “short circuit”.

The only difference from the first option is in the connection diagram and in the fact that when triggered, the loop is closed. It is rarely used in security alarms, at least I have not encountered this method.

3. Using a detector with loop power.

Although not often, such sensors are used. If in the first two cases the voltage is supplied via a separate line, then here the detector operates from the voltage supplied to the alarm loop by the control panel. In this case, the alarm signal is generated by an increase in DC current consumption, which is monitored by the control panel.

In this case, the number of connected sensors can be limited to a few pieces. The specific value for their various types must be indicated in the passport of the security device (as well as the possibility of using this option).

4. Addressable alarm loop.

If so far we have considered cases where current monitoring of alarm loops was carried out, then when using addressable detectors, information about their status is transmitted in digital form. Accordingly, the information content of the alarm system increases. The DS can diagnose its condition and transmit it to the control panel.

PARAMETERS AND FAULTS

Since the security alarm loop is an electrical circuit, it is characterized by such electrical parameters as current, voltage and resistance. Moreover, the first two are secondary, and the performance of the AL depends on the resistance, which determines its three main states:

"norm";
"break";
"closure".

The normal resistance of the loop should, as a rule, not exceed 1 kOhm, without taking into account the size of the terminal resistor.

It is worth explaining a little the principle of operation of the PKP-ShS-OU combination.

The device supplies voltage to the loop because in good condition the circuit is closed in it appears electric current. Its value characterizes the state of the AL. Normal current limits are set by the terminal device. Deviation in one direction or another triggers an alarm.

The resistance of the loop itself, and this also includes the resistance of the transition contacts in the sensors, determines the maximum permissible deviations. At short circuit the entire or part of the loop (one of the faults) increases the current consumption, and a break leads to its disappearance. This is the essence of current control.

Thus, there is another critical parameter - the leakage resistance between the wires of the loop, since it is a two-wire line, or “ground”, and one of the conductors. This characteristic is indicated in the control panel passport, but it would be better if its value is about 1 mOhm. Although many devices operate with leaks of several tens of kOhms.

In conclusion, one question that sometimes comes up: what is maximum length security alarm loop? The answer is any at which the electrical parameters discussed above are ensured.

* * *

The site materials are for informational purposes only and cannot be used as guidelines or official documents.

SECURITY - FIRE

Addressable alarm Compared to others, it probably has the only drawback - the relatively high cost of the devices.

Fire alarm

It is generally accepted that it is compensated by lower installation costs compared to a non-addressed system. Undoubtedly, but for fairly large objects. In addition, there are other features of this type of alarm that will be discussed here.

The system under consideration is good, first of all, because one line is enough to connect all the sensors (I’m not taking the power circuit into account yet). Of course, it is impossible to endlessly increase the number of sensors, for example for the Orion system (I will base further presentation on the example of this system) maximum quantity There are 127 addressable devices, but this is already a lot, and if the system is correctly configured, the possibilities will be almost limitless.

Figure 1 shows an addressable sensor connection diagram and its non-addressable analogue, where:

LS - communication line,
APS - control panel (device),
PKP - accepted control device,
ШС - alarm loop,
And - a detector.

This diagram does not add anything new to the above, but clearly illustrates the difference in the amount of installation work.

I would like to note one more point: addressable fire alarms have two undoubted advantages compared to conventional ones:

can use, if the room space allows, one fire detector instead of two analogue ones,
allows you to monitor the status of each sensor individually.

As for the rest, fire and security alarms built according to the address principle do not have significant differences between themselves.

The operating principle of addressable sensors differs from analog sensors in the method of signal transmission. The former transmit information about their status in digital form and, naturally, provide their individual number (address), determined when setting up the system.

One system configuration option (using the example of Orion equipment from NPO Bolid) is shown in Figure 2. Abbreviations and designations are as follows:

PC - personal computer. On its basis an automated workplace (automated workplace), in addition, it can be used to conveniently program and configure alarms. In the absence of an automated workstation, the constant presence of a PC in the system is not necessary.
PI - interface converter. The devices exchange information with each other via the RS-485 interface. And they are connected to a PC via a COM port via the RS-232 interface.
SK - network controller (remote control panel). Manages, coordinates, and saves the configuration of the system as a whole. You can also program the system through it, although it is less convenient.
BI, BU - here I combined display, control, keyboard, relay modules, etc.
PKP - receiving control devices, being addressable devices, allow you to connect conventional detectors (I), organized in familiar loops.
KDL - two-wire line controller - connects addressable detectors (sensors) to the system interface. In addition, in the presence of devices called addressable expanders (AP), it allows the use of conventional detectors, as is the case with control panels.

All devices are assigned individual addresses due to which they are uniquely identified by the system. Each of them has a number of internal settings.

I would like to note that the presence of all of the listed devices is not at all necessary. Addressable systems are built individually for each object, provide a wide range and flexibility of settings, and leave the possibility of subsequent expansion of the system at minimal cost.

ADDRESSED SECURITY ALARM

For large objects, a security alarm built according to the address principle is extremely convenient. This is determined by several factors:

significant reduction in installation work connecting lines;
the ability to localize the state of the system with an accuracy of one sensor;
ease of subsequent scaling;
the ability to quickly change the configuration.

The first point is quite obvious and evidence of this is given at the beginning of the article. The same applies to the localization of security detectors.

If we talk about scaling, then during the operation of a security alarm system the need for additional installation of sensors arises quite often. This could be caused by for various reasons, including additional blocking of vulnerable areas.

The targeted principle of constructing the system allows us to limit ourselves to installation work directly after installation additional equipment. It is connected to existing connecting lines.

In addition, when the organization guarding the facility changes, the requirements for building the system may also change. Addressable alarm makes it possible to make the necessary changes to its configuration in a matter of hours. Often it is enough to reprogram the desired zones and sections, which is, of course, extremely convenient.

Minimizing costs for installing addressable security alarms.

It is no secret that addressable detectors are quite expensive. To reduce the cost of purchasing them, you can make a compromise. We install conventional non-addressable sensors and connect them to devices called addressable expanders.

Of course, it is impractical to connect one single detector to the expander, so we proceed as follows:

we equip a separate room or zone using the traditional wired method;
We “hang” the corresponding group of devices on the expander.

As a result, we get a kind of hybrid that largely has the advantages of an addressable security system, but has a lower cost.

ADDRESSED FIRE ALARM

Here, the need to change the configuration arises quite rarely, except when connecting new premises to an existing fire alarm system or installing additional engineering technical equipment, which must be controlled by the fire protection system.

At the same time, when using addressable fire sensors we have:

the same savings on the installation of wire loops;
the ability in most cases to get by with one detector instead of two;
simpler implementation of alarm system status indication.

In general, targeted security and fire alarm equipment will be more expensive, moreover, it is not a fact that savings on installation work will cover this difference in price. However, the larger the object, the more preferable the address system is, if not in price, then in terms of ease of installation and operation.

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SECURITY ALARM LINE

TYPES AND TYPES - INSTALLATION

An alarm loop (AL) is an electrical circuit containing:

sensors (DS);
connecting wires;
terminal (OU), switching, as well as loop control devices (LCD).

This is the definition for a wired loop, and Figure 1 shows block diagrams the most common options.

I would like to draw your attention to the ambiguity in the interpretation of the state of dry contacts (relays) in the “classical” technical understanding and use for security alarm systems. It would be correct to call the contacts normally closed (NC) for a device that has them closed when not in use. For normally open (NO), naturally the opposite is true.

For some reason, alarm sensors (detectors) are considered to be in a closed state when the detector is turned on. Indeed, when the detector is turned on and goes into the “normal” state, the contacts close, but this is a working state, which means they must be considered NR. In order to avoid confusion, it is better to look at how the alarm signal is generated:

opening;
or by closing relay contacts.

The vast majority of sensors use the first option (Fig. 1a). I dwell on this in such detail so that you understand the principle of operation of the alarm loop and the security system as a whole. In the security mode, which is characterized by the supply of supply voltage to the detectors and the absence of influences causing the sensor to enter an alarm state, the AL is a closed circuit.

For the control panel (RCD), this is evidence that everything is normal at the controlled object. The control panel monitors the current flowing through the loop and if its value deviates upward or downward, it generates an alarm signal.

In order to provide the required current value, a terminal device is included in the loop - usually a resistor. Terminal devices may consist of other elements or combinations thereof, but this is not typical for most security systems.

By the way, the passport for the control device must indicate which element is used as the terminal element.

In order for current to appear in the loop, voltage must be applied to it. The PKP does this. Its terminal block indicates the polarity of the connection, which sometimes needs to be taken into account - more on that later.

Let's see in what cases the security alarm loop can open.

as a result of an impact on the sensor, causing it to go into an alarm state;
loss of supply voltage to active detectors;
break or short circuit of the electrical circuit.

The first mode indicates intrusion detection (except in cases of false alarms). The other two are the result of various components of the alarm system malfunctioning. By the way, if sensors are used that generate an alarm signal by closing the contacts (Fig. 2b), then in the “alarm” mode the loop will be closed.

TYPES AND TYPES OF SIGNALING LINES

Loops can be classified according to several criteria, for example:

method of connection to the device;
types of detectors used.

In the first case, two types can be distinguished: radial (Fig. 2a) and annular (Fig. 2b). The latter is quite rare and is used mainly in address systems ah fire alarm.

If we talk about the types of sensors used, then we can talk about threshold loops (Fig. 1a-b), which sharply change their electrical parameters when switching to the “alarm” mode, and address ones (Fig. 2c).

I have already talked about the first ones, but let’s look at addressable alarm loops now.

They are called so due to the addressable alarm sensors they use. In this case, information about the state of the sensor (in digital form) is transmitted over one two-wire line and the supply voltage is supplied. Due to the unique address, each detector can be uniquely identified by the system.

In this case, when connecting the loop, observe the polarity indicated on the terminals of the control panel and security sensors Necessarily. In addition, the number of detectors connected to the addressable AL is limited and is determined technical characteristics device.

INSTALLATION OF SECURITY Loops

Let's start with the fact that the alarm loop is a low-current circuit and its installation must be carried out taking into account the relevant standards and regulations. The main one is to ensure that when laying in parallel with power circuits, the distance between them is at least 50 cm.

How does an addressable fire alarm system work?

The intersection of these chains is allowed only at right angles, etc.

Since when laying the AL it is necessary to ensure its protection from accidental damage, it is not allowed to lay wires without attaching them to load-bearing structures. The most typical example of how not to do it and how it is done anyway is the free placement (dragging) of cables in the ceiling space, for example, behind Armstrong ceilings.

The governing documents of private security require, in order to avoid sagging of the connecting lines of security alarm systems, to fasten them in increments of, in my opinion, 50 cm to the walls and ceiling. With open installation, this becomes irrelevant, since there are electrical boxes and corrugated hoses that:

firstly, they allow you to comply with the rules for laying cables;
secondly, they simplify and speed up the installation process.

In addition to the requirements for the installation of alarm loops as low-current circuits, there are also rules for ensuring the reliability of their subsequent operation and ease of maintenance. There may be some contradictions here.

For example, from a maintenance point of view, access to the alarm system should be as convenient as possible, and from a security point of view, it is necessary to prevent the possibility of unauthorized access to wires and sensors.

Moreover, if during protected times it is difficult to carry out any manipulations with the loop, then during the period when the alarm system is disabled, turn off part of the loop or sensors for knowledgeable person won't be difficult. Moreover, after this the alarm will work as before, only part or all of the premises will be unprotected.

To solve this problem, the following measures can be taken:

sealing (sealing) of instrument cases, distribution boxes, places of possible opening of electrical boxes;
hidden installation of alarm sensors;
installation of loop monitoring devices.

The first two points are quite obvious. The AL monitoring device allows you to determine its breakage. On the one hand, it may indicate a malfunction of the loop, on the other hand, it will indicate that part of the loop is disconnected. The connection of the remote control unit is made at the point farthest from the control panel and its visual control must be carried out every time the object is put under protection.

However, the above applies to security systems, installed in places with stay large quantity unauthorized persons: shops, offices, etc. The risk of such interference in an alarm system installed in a country house, in a private house or apartment is practically absent.

© 2014-2018 All rights reserved.
The materials on the site are for informational purposes only and cannot be used as guidelines or regulatory documents.

Heat detector "Bolid"

Fire, in addition to light and heat, if handled carelessly or due to a coincidence of circumstances, can bring a lot of troubles and destruction. This is especially true for multi-story buildings with their huge vertical air draft and storage facilities with explosives.

The only way to save people's lives, personal and government property from destruction in fire is to install fire alarm systems on site. Detectors "Bolid" various types, are indicators that can quickly signal the start of a fire.

Purpose and areas of application

Bolid detectors are the basis of the fire security system. With their help, the surrounding space is monitored, scanned, information is processed and sent to control devices.

Note: With the help of various Bolid detectors, devices are activated, both signaling fires and fire extinguishing systems.

Since a fire is characterized by factors such as increased temperature, smoke and ultraviolet radiation, Bolid detectors are manufactured to respond to these signs of fire.

Thus, in fire alarm systems, fire detectors “Bolid” of this type are used:

Flame detectors.
Thermal sensors.
Smoke detectors.
Combined instruments.

The most functional is the Bolid aspiration detector, which actively scans the surrounding space, analyzing its indicators such as heat, smoke and gas pollution. It is distinguished not only by its versatility, but also by its high price, which starts at 20,000 rubles.

Flame detectors

Flame sensors

Flame detectors "Bolid" are used in places where explosive and flammable substances are stored. In addition, this is the only type of sensor that can operate on open areas. Air movement in open areas makes it impossible to use smoke, heat and gas detectors.

Flame detectors are used at the following facilities:

offshore drilling rigs;
decks of tankers transporting oil and liquefied gas;
gas and oil production installations;
gas pipelines;
petrochemical industry enterprises;
gas stations;
warehouses with explosives and flammable substances;
pyrotechnic factories.

The task of the "Bolid" flame detectors is to detect a fire at the moment of its occurrence, with subsequent implementation automatic system fire extinguishing

The operating principle of Bolid detectors of this type is to detect ultraviolet radiation, which is characteristic only of flame. Sensors do not respond to light from lamps, solar radiation and heat. The degree of reliability of these devices corresponds to their price, which ranges from 40,000 to 70,000 rubles.

Thermal sensors

These devices are designed to provide an appropriate signal when the temperature at a protected facility increases. For indoor use only. They issue a signal when a threshold temperature level is reached or based on the results of an analysis by the device of the rate of its increase.

Thermal addressable detector“Bolid” detects fire in a comprehensive manner - in both ways, which increases the reliability of the device and eliminates the giving of false signals. Heat detectors“Bolid” can be installed in rooms with or without heating.

Their installation location can be:

garages;
premises in offices and other similar institutions;
shopping, entertainment centers and sports facilities;
warehouses for materials with a slow burning rate;
medical institutions;
schools and kindergartens.

Thanks to simple device, low price (200-500 rubles) and ease of installation, thermal sensors are in great demand and popularity among many organizations.

Smoke detectors

Smoke sensor

In terms of the speed of detecting signs of fire, Bolid smoke detectors occupy a middle position between fire and heat detectors. Sensors of this type can operate both as part of alarm systems and independently.

There are two types of smoke capture devices - point and linear:

Point sensors consist of a housing, a smoke chamber, an optical unit and printed circuit board. They are usually installed on ceilings and control a certain area. They have a small cost, in the range of 300-500 rubles.
The linear detector "Bolid" is a optical system, consisting of both a transmitter and a receiver. They are installed at different ends of the premises, as close as possible to the ceiling, and control a significant distance (50-140 m). Modern linear emitters are equipped with a self-monitoring system that amplifies the signal when the optics become dusty. Their price is quite high (from 4,000 rubles), but this is compensated by the lack of an abundance of wires and the speed of installation.

They are installed only in enclosed spaces.

These can be the following objects:

kitchens and corridors in residential apartments;
agricultural buildings - cowsheds, pigsties, poultry farms and granaries;
garages and underground parking;
warehouses and storage facilities;
cabins of ships and ships;
aircraft cabins and luggage compartments;
passenger railway cars;
basements, entrances of various buildings and structures;
schools, kindergartens, clinics and hospitals;
repair shops and car services.

Smoke detectors use an electro-optical system. The principle of its operation is based on changing the electrical parameters of the photosensor when the transparency of the air decreases. Smoke detectors have a sufficient degree of reliability and speed of fire detection. Thanks to this and their affordable price, they are most popular.

Combined detectors

Combination device

These devices combine gas, smoke, heat sensors and sensors that capture infrared radiation.

Features of addressable fire alarm

Allows to detect fire at the earliest stage. Various systems duplicate each other, eliminating errors and false signals.

Combined devices can operate autonomously and as part of security systems.

They perform the following functions:

Measure the air temperature.
Air is taken and carried out chemical analysis for the presence of combustion products.
Monitor the presence of smoke in the room.
Using IR sensors, they scan the space to detect radiation of a given range.
Digital processing of the received information is carried out.
They supply information to the indicator and to the security system loop.

These products are installed at the following facilities:

offices management team and in places where valuable equipment and important documentation are located;
banking institutions and savings banks;
warehouses and storage facilities with flammable materials.

At high degree These devices are completely reliable affordable price, which ranges from 1000-1800 rubles.

Addressable sensors "Bolid"

Addressable detectors

Addressable sensors "Bolid" are used in systems fire and security alarms. With the help of software, such a device has its place on the diagram, and the operator can determine the place where the alarm signal comes from.

Address security detectors"Bolid" are available in two types:

Manual. Switching on and off devices of this type is done manually by pressing a button. The Bolid addressable manual fire call point is one example of such a device.
Radio channel fire detector "Bolid". This type of sensor receives and transmits signals via radio, with a range of up to 600 meters.

The use of radio-channel smoke and heat addressable detectors "Bolid" allows not only to speed up the process of installing an alarm system, but also to significantly reduce its cost by reducing cable consumption and the amount of work.

Programming of the Bolid addressable sensors is carried out after they are installed in place and tested for functionality. This is done from the control panel or personal computer. The device can be assigned absolutely any number, regardless of what it had before. To do this, you need to enter the appropriate command to change the old address and dial the new address.

The use of addressable sensors allows you to accurately determine the location of a fire and take timely measures to eliminate it and evacuate people from the building.

Video about fire detector

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Eternal theme: 1, 2, 3 or 4? Fire detectors for one room

How many fire detectors, what types and to generate what signals should there be in one room?

A.M. Omelyanchuk

Head of the design bureau of the company "SIGMA-IS"

Question about the number of fire detectors in one room in lately considered almost indecent. The specialists frown or laugh, but avoid the question, usually making a joke, saying, put a 4 - it’s better to be on the safe side. Or they begin to talk about how SP5 should be changed so that everything is correct and understandable. On the other hand, design practitioners are now forced to create projects based on the existing SP5.

Without pretending to cover possible situations completely, I will try to outline practical recommendations based on the already accumulated experience of living with technical regulations and new sets of rules.

What is mandatory and what is the exception?

Requirements for the number of detectors are specified in SP 5.13130.2009 in paragraphs 13.3.2-13.3.3 and 14.1-14.3 and appendices O and R. I will not quote the text in full - the main points are very long and not very clear. If you want, find it and read it. Just keep in mind that this summer minor changes were made to clause 14.2 to make it a little clearer.

The greatest discrepancy in relation to the main text (sections 13 and 14) is caused by the question “Is it necessary to comply with all of the specified points or do some of them describe exceptions, and from what requirements of which points are exceptions made in this case?”

In general, the most logically consistent interpretation seems to me to be that given in Table. 1.

Applicability of Annex P

Now a few explanations on how to determine which cell of the table. 1 applies to your specific case.

Appendix P is mentioned in the paragraph where it talks about the use of “increased reliability detectors”, and it, in theory, describes the characteristics of such (increased reliability) detectors.

Precise to the spark. How does an addressable fire alarm system work?

As can be seen in table. 1, the applicability of Appendix P can greatly influence the answer. I will give this application in full:

R.1 Use of analysis equipment physical characteristics fire factors and (or) the dynamics of their change and providing information about its technical condition(for example, dust).
R.2 Use of equipment and its operating modes that exclude the impact on detectors or loops of short-term factors not related to fire

The applicability of Appendix P to specific detectors is a matter of faith and marketing efforts by the manufacturer.

If you say that no existing detector satisfies these requirements, I cannot argue with anything. Indeed, it is impossible to protect against all short-term factors. Indeed, detectors do not analyze physical characteristics - they simply measure them.
If you say that any (at least any optical) smoke detector satisfies these requirements, I will also have to agree. Indeed, all detectors undergo pulse testing electromagnetic interference. Indeed, all detectors detect changes in certain physical parameters of the environment associated with fire (fire factors).

In practice, it is usually considered that all addressable analogue detectors certainly satisfy Appendix P, while non-addressable ones do not (I repeat once again, “home alone” type detectors, in my opinion, are better than conventional non-addressable ones, but are they good enough to fall under Appendix P is a matter of trust in a particular manufacturer).

Applicability of Appendix O

The appendix is long and I won’t quote it in full. Briefly, its essence is that the estimated time for detecting and eliminating a malfunction (replacing a detector) should not exceed 70% of the permissible time to stop the enterprise’s activities or the time for which control functions can be “transferred to dedicated personnel.”

Please note that this implies an immediate shutdown of the organization’s activities for the duration of a malfunction of even a single detector. Although the standard methodology for calculating risks considers a normal situation when the alarm system in each room does not work 20% of the time. Therefore, if you draw up STU (special technical specifications) for your facility with risk calculations, you can justify very leisurely work repair service and, of course, without any interruption of the enterprise’s activities.

What is important for us now is that in order to apply Annex O, it is necessary that the indication of a faulty detector on the control panel be provided. The address systems known to me provide this. The admissibility of applying this paragraph in the case of non-addressed detectors of the “home alone” type and similar ones, capable of generating such a notification on non-addressed loops, can be challenged by representatives of the State Fire Inspectorate, although in the case of installing only one such detector on a non-addressed loop, the requirement is undoubtedly met. The point is that these non-addressable detectors indicate only the fact of a malfunction, and in order to identify the specific detector that generated this event (if there are several of them on a loop), you need to personally go around the entire loop and find the faulty one with your eyes.

Recommendations for talking with the inspector Now let’s forget about “alarm only,” because any alarm with a siren is already a “type 1 warning system.” Taking into account the indicated notes (that any addressable systems can be brought under Appendix O, and addressable analog systems under Appendix P), and also taking into account that almost all domestic non-addressable devices are two-threshold, we can shorten the table. 1 to easy to remember table. 2.

Let me remind you that, following the letter of the law, addressable and addressable-analog devices in themselves do not have any advantage. Formally, we are talking about “increased reliability” or “fault detection”. But since today there is no clear explanation of what kind of malfunctions should be detected, in what time, and even more so there is no clear formulation of what “increased reliability” is, then in the practice of approving projects in the examination and in the practice of carrying out gas pumping inspections, approximately the following understanding has developed .

Don’t forget, a particular expert or inspector’s interpretation of the vague wording of the set of rules may differ from mine, and it is useless to refer to my article in a conversation with him. They will very easily explain to you that any multi-criteria addressable analogue laser blue detector does not sufficiently comply with Appendix P. However, if the inspector is not just looking for something to complain about, but is already in the mood for a constructive conversation, then the above interpretation will most likely be suitable. Just remember that application of Appendix O may require a time estimate agreed upon by the customer to replace a faulty detector.

For large rooms

Now remember that all of the above applies to small rooms. If the room is large, then there will obviously be a lot of detectors, spaced at distances no greater than the standard ones - depending on the height of the ceiling, the type of detector and the size of the room. In this case, the question is formulated differently: is it necessary to use half the standard distance between detectors or is it not necessary to use half the distance. I present it in the form of a table. 3.

Please note that Appendix O in this case does not play any role, because in each room there are undoubtedly more than two detectors, and therefore the question of redundancy due to the failure of a separate detector no longer arises.

What will European standards bring?

In conclusion, I will say that after the transition to a method for testing detectors that complies with European standards (fire tests), I see no point in clinging to the remnants of “sovereign fire standards” and expect a very rapid transition completely to European standards (EN 54), in which questions “1, 2, 3 or 4?", included in the title, is simply not there.

Archive of publications

How to save your property, and sometimes even your life, from the destructive power of fire? Follow the rules for using electrical appliances, do not smoke in bed, and do not allow children to play with matches.

This list can be continued, but what if the fire happened at night or during the day when no one was in the apartment?

Of course, the neighbors, hearing the smell of smoke, will call rescuers, but will they arrive in time? The ideal answer to all these questions is to install an alarm system in the room, the main element of which is an addressable smoke fire detector.

He will be able to send a signal to the control panel immediately when the first signs of fire appear and thereby help save your property from fire.

Design and principle of operation
Scope and areas of application
Model overview
Advice and opinions from experts
Let's sum it up

Sensor design and operating principle

Addressable smoke sensors are an important component of the alarm system. It transmits encoded information to the control panel, which includes the address of the device itself or its personal number in the loop, as well as controlled parameters. At the same time, it can be used to receive a signal to turn on the indicator.

Very often, addressable detectors are produced for a specific device. They are capable, depending on the type, of transmitting information about the level of smoke or temperature in the controlled building. The control panel, having received them, analyzes the information and submits it to the operator, and also turns the equipment on or off.

A significant number of such devices can be included in one loop, and each of them will have its own unique number, which can be easily determined from the remote control. This approach makes it easy to determine in which room the alarm went off.

It can be powered either through a separate pair of wires or through the same one through which information is exchanged. This approach is used in many systems:

Scope of application

What is this system alarm? It was first developed and implemented by foreign specialists and only then was it appreciated by domestic companies.

What is addressable fire alarm and what are its advantages?

The same fire detector remains its main component. And as before, the efficiency of the entire system depends on its quality and reliability. However, significant differences also emerged.

Each sensor is constantly in the process of communicating with the central console, reporting to it information about its status, which includes information about:

Smoke
Component performance
Dust levels

Moreover, each detector has its own communication channel, and the connection can be made by any of available ways. Therefore, it is allowed to install address sensors in fewer numbers than threshold ones.

There are differences in the topology of the circuit construction and the algorithm for polling devices. The control panel of the addressable polling system cyclically polls detectors to determine their status.

In this case, one of four types of signals can come from the device:

Norm
Absence
Malfunction
Fire

The advantages of address systems include:

Possibility of monitoring the operation of detectors
Value for money
Informativeness of messages

But at the same time, they have one significant drawback - an increase in the time of fire detection.

Review of popular models

In the modern market of fire systems, addressable detectors are presented in a wide range. Among them, the following models are in greatest demand:

Smoke optical-electronic (2251EM)
Thermal maximum differential (5251REM)
Threshold (5251NTEM)
Combined (2251TEM)
Laser (LZR)
Optical Smoke (FTX-P1)

In them, information is transmitted using digital messages generated by a microprocessor board. They are received by addressable control panels, modules and expanders.

As an example, we can consider addressable fire alarm sensors developed by one of the most famous foreign companies System Sensor, IP212/101-3A-AIR. It combines optical-electronic and thermal maximum-differential sensors, which has significantly increased the efficiency of signaling. When used, it provides protection against any type of fire.

This device fully complies regulatory requirements, which allows you to install one addressable detector in a room, instead of two addressless ones.

When a fire is detected, it transmits a “fire” signal to the control panel. These sensors are mainly used for industrial enterprises and other social and cultural institutions.

Efficiency of address systems - expert opinion

Why are such systems most often chosen? Because when installing them you can significantly reduce the cost of installation work And consumables. Addressable systems are able to monitor the status of detectors, thereby significantly increasing operational reliability. They help reduce labor costs service, thanks to the use of a ring structure of the address communication line.

Another important positive factor is the possibility of addressable control of all automation. It should be taken into account that all addressable devices are connected to a common communication line, and this made it possible to avoid laying additional circuits.

Bottom line

Admiring the possibilities, criticizing the high cost and arguing about the areas of application of addressable systems, one cannot achieve full description their effectiveness.

After all, most of the reasoning is superficial. And an objective assessment can only be obtained by analyzing the opinions of all interested parties, including manufacturers.

They are the ones who know everything about their systems and are able to tell what the advantages of their equipment really are. And addressable sensors actually have enough capabilities to work effectively.

They allow you not to waste precious time for such situations and allow the entire system to function extremely harmoniously. And this, in turn, guarantees reliable protection of your property from fire.

Articles and Lifehacks

Many ordinary people have heard many times, but actually do not know what is a loop in a phone. In practice, this part is usually understood as one of the most important components in the device. Those who know also deal with this spare part. The part is intended to connect together several movable fragments of a mobile device at the same time. The cable is designed to transmit an electronic signal from one part of the phone to another. Thus, experts distinguish joystick cables, display cables, speaker cables, and inter-board cables.

What types of cables are there in a phone?

In smartphones, as in cell phones, several of these types of components may be present at the same time. They are aimed at ensuring the functioning of a number of elements. For example, in some models of cellular devices there are cables responsible for the presence of a flash. Other devices are equipped with cables with a charging connector or a SIM connector. That is why those craftsmen who decide to repair their phone themselves must first make sure what type of component they need, and only then go to the store to buy it.

Independent loops

It is important to remember that some modern devices also contain multi-component types of this part. Here it is important to understand what a cable in a phone is and what it can do in operation. These parts are not just connecting components of other parts of the device. They themselves act as the main carriers in the phone. The most striking example of this type of component is the cable in Apple iPhone 5. It comes with a charging connector. In addition, the part is supplemented with a microphone, Home button contacts, a GSM antenna and a headset jack.

Auxiliary cables

Special attention should be paid to the cables, which are not independent fragments in the phone, but auxiliary parts. Their main task is to connect other important fragments. They don't expand it, they just make it work. As a rule, their damage results in a faulty screen. It either becomes completely white, or, on the contrary, goes out. However, cables in this situation cannot be purchased separately. In stores, in most cases, they are sold together with a touchscreen or display, that is, the main fragment of a telephone device. Inter-board cables are usually present in sliders or so-called clamshells. They rarely last forever. On the contrary, such a part has the tendency to wear out and fail. Moreover, this fragment can be easily changed not only by the hands of a professional. Repairs can also be carried out on your own.