circuit diagram ventilation automation systems, as a rule, are developed at the design stage of building engineering complexes, at the same time the issue of the preferred control mode (semi-automatic or automatic) is being decided. Control cabinets must be installed in maximum accessible place so that, if necessary, it is easy to control the equipment and carry out its regular service.

Automatic control allows:

Regulate the intensity of the fans;
Timely prevent freezing of the water heater;
Support optimal temperature air and other indicators affecting life.

The concept of automation

Ventilation automation is provided by special cabinets installed in the building, which are responsible for the automatic control of all available ventilation and climate control equipment. Automation can be carried out on any objects, ventilation systems which are complicated schemes or complexes of medium complexity. Modern automation elements perform several functions simultaneously, and due to this, the owner is protected from inevitable (in the case when there is no single control) system failures.

Reasons for the demand for automated ventilation systems

Ventilation systems, in most cases, are complex combinations of engineering equipment designed to provide efficient air exchange. Manual control is not rational here, since pressure, humidity and temperature indicators are constantly changing depending on the season, climatic conditions, the amount of removed and incoming air changes. The ideal solution will be full automation of ventilation and air conditioning systems.

Necessary equipment

The main elements that ensure ventilation automation:

Regulators- key components, it is they who coordinate the activities of the actuators based on the indicators of the available sensors;
Sensors- the components on the basis of which the automation system is formed, they provide information about the current state of the controlled object. Sensors provide feedback on each individual parameter - humidity, temperature, pressure, etc. The criteria for choosing sensors are operating conditions, the required measurement accuracy, and the range of indicators.
Executive mechanisms– electrical, hydraulic, mechanical actuators.

Benefits of using automated ventilation systems:

Noticeable saving electricity (costs are reduced by about 20%);
Remote control and adjustment of the system elements;
Indication required parameters system functioning;
Possibility regulation of climatic characteristics indoor air;
Pollution Intensity Tracking filters, providing timely service;
Efficiency control equipment, protection against hypothermia, overheating of system elements.

To date, automation of ventilation is carried out not only in industrial facilities, it is also relevant for most residential, public buildings. Its main task is to provide the most comfortable air space in the room.

Air conditioning: Automatic maintenance in enclosed spaces of all or individual air parameters (temperature, relative humidity, cleanliness, speed of movement and quality) in order to ensure, as a rule, optimal meteorological conditions, the most favorable for the well-being of people, maintaining technological process, ensuring the safety of valuables (SP 60.13330.2012).

Air conditioning systems are divided into three main groups:

split system. This is an air conditioning system consisting of two blocks: external (compressor-condensing unit) and internal (evaporative). The principle of operation of the system is based on the removal of heat from the air-conditioned room and its transfer to the street. Split system, like any air conditioning system, works on the same physical principles as a household refrigerator.

Central air conditioning systems combined with ventilation systems. The main task of such systems is to maintain the appropriate parameters air environment: temperature, relative humidity, purity and mobility of air in all rooms of the facility using one or more technological installations, due to the distribution of flows using a piping system.

At the same time, the correct composition of the air is maintained more by ventilation than by air conditioning. Forced ventilation is responsible for the influx of fresh air, exhaust - for extracting harmful impurities.

The supply unit is used to process air and supply it to the serviced premises. Air treatment refers to its purification from dust and other contaminants, cooling, heating, dehumidification or humidification.

Multizone systems. They are used for objects large quantity rooms where there is a need for individual regulation of air temperature and special requirements according to the comfort of the premises, for example, server rooms or technological equipment requiring a large heat sink. Structurally, the multizone system consists of one or more outdoor units connected by refrigerant pipelines, electric cables power supply and control with the required number of indoor units of wall, floor-ceiling, cassette and duct versions.

The most common multi-zone systems are chillers, fan coil units, central air conditioners.

The automation system allows the air conditioning system to provide the necessary, sometimes significantly different, parameters in the premises, while avoiding excessive energy consumption (VRV and VRF systems).

Possible design error: Do not separate northern and southern contours heating and air conditioning in large buildings. As a result, one half of the workers are in comfort, while the other half either freezes or overheats.

Components of the system

System management central air conditioning, combined with the ventilation system, can be decomposed into the control of the following parts:

In multi-zone air conditioning systems, the operating modes of the outdoor (central) unit, the operating modes of each of the indoor units, and the distribution of refrigeration power along the circuits are controlled. In these systems, each indoor unit is equipped with an electronic expansion valve that regulates the amount of incoming refrigerant from the common circuit depending on the heat load on this unit. As a result, the system is better than conventional household split systems maintains the set temperature.

What parameters can be controlled

Automation of ventilation and air conditioning systems allows them to perform the following functions:

Regulate the temperature and humidity of the air entering the system of supply channels;
Maintain air parameters within sanitary norms with multiple management tools;
Switch air conditioning and ventilation systems to energy-saving operating modes during low load hours;
If necessary, transfer systems to non-standard and emergency modes of operation;
Display of technological parameters of individual nodes of the ventilation system on local control panels;
Notify the operator if the parameters of individual devices and assemblies fail or go beyond the settings, as well as if any components of the ventilation system are in working order, although according to the regulations they must be turned off.

Technical means of automation of ventilation and air conditioning systems include:

Primary converters (sensors);
Secondary appliances;
Automatic regulators and control computers;
Executive mechanisms and regulatory bodies;
Electrical control equipment for electric drives.

The operating parameters of the devices and the readings of the sensors, the monitoring of which is necessary for the correct and economical operation of the system, are displayed on local control panels and on the consoles of the dispatching system. Control of intermediate parameters can be displayed on the monitor automatically, when leaving the specified range, or through nested menus for each of the subsystems.

Supply ventilation systems are equipped with devices for measuring:

Air temperatures in serviced premises, outdoors, and at intermediate points;
Temperatures and pressures of water (steam or refrigerant) before and after air heaters (air conditioners), compressors, circulation pumps, heat exchangers and at other critical points of the process;
Air pressure drops on the filters of ventilation units;
Energy parameters of the system units.

Air conditioning units are additionally equipped with instruments for measuring pressure and temperature cold water or brine from the refrigeration station, as well as temperature and humidity devices in the course of air processing.

In the central air conditioning system, the temperature in the room is controlled by changing the air exchange rate (the supply air temperature is set for the system as a whole). In multizone systems, it is possible to more accurately set the temperature for each of the rooms by changing the mode of the indoor units with refrigerant or heat carrier (closers).

Sensors

The following types of sensors are used in the air conditioning system:

Temperature control sensors supply air and indoor air;
Concentration control sensors in the indoor air of carbon dioxide CO2;
Humidity control sensors air;
Sensors for monitoring the condition and operation of equipment(pressure and air flow velocity in air ducts, temperature sensors, pressure or flow sensors for devices with liquid circulating through pipelines, etc.).

The output signals from the sensors are sent to the control cabinet to analyze the received data and select the appropriate algorithm for the operation of the air conditioning system.

Temperature controllers

Temperature controllers are the control element of the system and are mechanical and electronic. Using the thermostat, the user can set the conditions that he considers comfortable

Mechanical thermostats. They consist of a thermal head (sensing element) and a valve. When the air temperature in the refrigerated room changes, the sensitive element reacts to this and moves the regulator valve stem. This change in stroke regulates the supply of cold air.

Electronic thermostats. These are automatic devices, control panels that maintain the set temperature in the room. In the air cooling system, they automatically control indoor unit(by changing the refrigerant flow rate or fan speed), the purpose of their operation is to create indoor temperature regime, set by the user.

Mechanical and electronic air thermostats differ only in the way they set the temperature. Their temperature control mechanism is identical - according to a signal transmitted via cable line. This is their difference from regulators on radiator batteries.

Actuator drives

To executive devices air conditioning systems- air valves and dampers, fans, pumps, compressors, as well as heaters, coolers, etc. electric or pneumatic actuators are connected, through which the system is controlled. They allow:

Stepwise or smoothly (when using frequency converters) adjust the fan speed;
manage state air valves and shutters;
The performance of duct heaters and coolers is regulated;
Regulate the performance of circulation pumps;
Humidifiers and dehumidifiers, etc. are controlled.

The analysis of signals from the sensors, the choice of the operation algorithm, the transmission of the command to the drive and the control of the execution of the command takes place in the controllers and servers of the automation system.

Control of electric motors of compressors, pumps and fans, especially with a power of more than 1 kW, is most economically carried out with the help of frequency converters. The figure shows the possible economic effect of the use of inverters in air conditioning systems.

Air conditioning automation boards

Automation boards are a tool designed to control the air conditioning and ventilation system. The main element of the control panel is a microprocessor controller. Automation system controllers are produced freely programmable, which allows them to be used in systems of various sizes and purposes.

When connecting sensors to the automation panel of the air conditioning system, the type of signal transmitted by the converter is taken into account - analog, discrete or threshold. Expansion modules that control device drives are selected based on the type of control signal and control protocol.

After programming, the controller brings the system to the specified parameters and the time cycle of operation, then the system can function, in full automatic mode carried out:

Analysis of the readings received from the sensors, data processing and making adjustments to the operation of the equipment to maintain the specified parameters of the environment inside the room;
Output of information about the system to the operator;
Monitoring the operation and condition of air conditioning equipment with displaying information on display boards;
Protection of equipment from short circuit, overheating, avoidance of incorrect operating modes, etc.;
Monitoring the timely replacement of filters and maintenance.

Design of air conditioning automation system

The air conditioning automation project is carried out taking into account technological requirements OF design specialists:

Refrigerating machines, circulation pumps, two- and three-way valves, and other equipment are subject to automation;
Summer, winter, transitional, emergency modes of operation of systems are taken into account;
Provides synchronization of work refrigeration machines, circulation pump valves;
Provide switching of the main and reserve pumps, for a uniform expenditure of a resource;
They provide for the transfer of information to the building management system and reactions when an alarm signal is received from the fire alarm system.

A typical composition of an air conditioning automation project contains sheets:

System operating modes. Work in the building automation and dispatching system

Control panels can operate in three main control modes:

Manual mode. Using a remote control connected to the automation board, it can be placed directly on the board, or it can be on/off buttons. The operator manually, directly on the switchboard, or remotely selects the operating mode of the system depending on the parameters of the room environment.

Auto offline mode . In this case, switching on, switching off, selection of the operating mode of the system occurs autonomously, without taking into account the data of other climate systems, with notification of the dispatching system.

Auto mode taking into account the algorithms of the building management system. In this mode, the heating operation is synchronized with other life support systems of the building. More about

Ventilation (V) and air conditioning (AC) contains two contradictory conditions: the first is simplicity and reliability of operation, the second is high quality functioning.

The basic principle in technical organization automatic control CB and SLE is functional design hierarchical structure of protection, regulation and control tasks to be performed.

Any industrial SCR must be equipped with elements and devices for automatic start and stop, as well as emergency protection devices. This is the first level of VCS automation.

The second level of SCR automation is the level of stabilization of equipment operation modes.

The solution of problems of the third level of control is associated with the processing of information and the formation of control actions by solving discrete logic functions or performing a number of specific calculations.

The three-level structure of the technical implementation of the control and regulation of the operation of the SCR allows the organization of the operation of systems depending on the specifics of the enterprise and its maintenance services. Regulation of air conditioning systems is based on the analysis of stationary and non-stationary thermal processes. The next task is to automate the adopted technological scheme for controlling the SCR, which will automatically provide the specified mode of operation and regulation. individual elements and systems in general optimal mode.

Real or cumulative maintenance of the specified operating modes of the SCR is carried out by automation devices and devices that form both simple local control loops and complex multi-loop automatic control systems (ACS). The quality of ACS operation is determined mainly by the correspondence of the microclimate parameters created in the premises of a building or structure to their required values and depends on the correct choice of both the technological scheme and its equipment, and the elements of the automatic control system of this scheme.

Automation of the supply ventilation system

When regulating the heat output supply systems the most common is the method of changing the flow rate of the coolant. There is also a method of automatic control of the air temperature at the outlet of the supply chamber by changing the air flow. However, when these methods are used separately, the maximum allowable use of the heat carrier energy is not ensured.

In order to increase the efficiency and speed of the control process, it is possible to apply a cumulative method for changing the heat output of the unit's air heaters. In this case, the supply chamber automatic control system provides for: selection of the supply chamber control method (local, local buttons, automatic from the automation panel), as well as winter and summer operation modes; regulation of the supply air temperature by acting on the actuator of the valve on the heat carrier; automatic change in the ratio of air flow through the air heaters and the bypass channel; protection of air heaters from freezing in the supply chamber operation mode and in the backup parking mode; automatic shutdown fans when the frost protection is activated during operation; automatic connection of the control circuit and opening of the outside air inlet valve when the fan is turned on; air heater freezing danger alarm; signaling the normal operation of the supply chamber in automatic mode and preparation for launch.

The automatic control system of the supply chamber (Fig. 1) works as follows. The choice of control method is made by turning the switch SA 1 to the "manual" or "automatic" position, and the choice of the operating mode - by the switch SA 2 by turning it to the "winter" or "summer" position,

Manual local government electric motor supply fan M1 produced by buttons SB 1 "Stop" andSB 2 "Start" through a magnetic starter KM ; executive mechanism M2 outside air intake damper with buttons SB 5 "Opening" and SB 6 "Closing" through intermediate relays and own limit switches; executive mechanism MOH valves on the heating medium with buttons SB 7 "Opening" and SB 8 "Closing" via intermediate relay K5 and own limit switches and actuator M4 front bypass valve with buttons SB9 , SB 10.

Switching on - switching off the electric motor M 1 fan is signaled by a lamp H L 1 "Fan on" installed on the automation board.

Fig 1. Functional diagram supply chamber control

Switching the supply chamber on and off in the automatic mode of operation is done using the buttons SB 3 "Stop" and SB 4 "Start", located on the automation board, through intermediate relays K1 and. K2 . In this case, before turning on the fan, intermediate relays K1 , KZ and K6 provide forced opening of the valve on the coolant, and after turning on the fan, an intermediate relay K2 connects the supply air temperature control circuit and frost protection, and opens the fresh air intake damper.

Supply air temperature is maintained by a temperature controller R2 with thermistor sensor VK1 , installed in the supply air duct; control signal via relay-pulse interrupter P1 applied to the actuator MOH coolant valve.

The change in the ratio of air flow through the heaters and the bypass channel is carried out according to the signals of the temperature controller R4 with sensor VK2 , installed in the heat carrier pipeline. Control signals via relay-pulse interrupter RZ fed to the actuator M4 front bypass valve.

Protection of the air-heating installation against freezing is provided by a sensor - a coolant temperature switch R5 , the sensitive element of which is installed in the coolant pipeline immediately after the first heating section along the air flow, and the air temperature sensor-relay R6 the sensitive element of which is installed in the air duct between the outside air inlet damper and the air heater. In the event of a risk of freezing via an intermediate relay K6 motor is switched off M 1 supply fan, opening the damper on the heating medium and activating the alarm, as well as closing the outside air inlet damper. The occurrence of a risk of freezing is signaled by a lamp HL 3 "Freezing Hazard" and sound signal ON THE .

Preparing to start the fan after pressing the button SB 4 signaled by a lamp HL 2 (only for winter mode).

Automation of the operation of a group of supply systems

In industrial ventilation systems, the use of a group of supply systems operating in the mode of maintaining the same supply air temperature is widespread. To do this, the automation scheme provides for automatic control of the heat output of air heaters by changing the temperature of the supplied coolant at a constant flow rate of air and coolant through them by mixing part of the coolant from the return line into the supply line. A simplified functional diagram of the control system for a group of supply ventilation chambers is shown in fig. 2. In this scheme, a group of air-heating units of supply chambers PC1-PC P ,

Fig. 2 Functional diagram for controlling a group of supply chambers

connected in parallel along the coolant, connected to the coolant preparation unit, consisting of pumps H 1 and H2 (one spare) check valve K1 control valve K2 and pressure regulator RD . On the return pipeline a coolant flow switch is installed in front of the preparation unit RPT .

Valve actuator K2 electrically connected to the regulator RT1 , to the inputs of which sensors are connected DT temperature of the heat carrier in the supply line at the outlet of the preparation unit and the sensor Days in. outside air temperature. The diagram also shows elements of signaling equipment: supply air temperature alarm RT2 with sensors D1 -DP and air flow switch RPV , installed in each supply chamber. signaling device RT2 structurally made in the form of a regulating multi-point bridge KSM , the output contacts of which, as well as the contacts RPV , close the circuits of light and sound alarms.

The developed system provides control of a group of supply chambers in manual and automatic modes.

In manual control mode, the system allows you to start and stop the fan motor of any supply chamber PC1-PKP; run in the appropriate direction and stop the control valve actuator K2 ; run in the appropriate direction and stop the actuators of any air valve.

In the automatic control mode, the system allows you to programmatically start and turn off the supply chambers PC1-PKP , automatic maintenance of the set air temperature at the outlet of the supply chambers; control of the coolant temperature at the outlet of the air heater, temperature and air velocity at the outlet of the supply chambers with emergency mode alarm.

The system is turned on and the "Manual-automatic" mode is selected from a remote panel.

In mode manual control when the pump selection switch is moved to the “O” position, the pump motors are controlled by locally installed “Start” and “Stop” buttons. Buttons for manual control of fan motors, valve actuators are also installed there. K2 and air intake valves.

In the automatic control mode, when the operation mode switches are set to the “automatic” position and the pump is selected to the position 1 and 2 button located on the remote board, the group of supply chambers is programmatically launched. At the same time, the signal lamp lights up, indicating that the automatic control is switched on. The selected one is turned on first. circulation pump and the control valve opens. K2 . After a 5-minute warm-up of the heaters, the electric motors of the fans are automatically switched on and the air intake valves open. After the air valves are fully opened, the limit microswitches are activated, connecting the alarm and control circuits of the supply chambers to the operation. In the absence or decrease in the flow rate of the coolant, the relay is activated RPT and de-energizes the intermediate relay, which, in turn, opens the contacts for powering the magnetic starters of the fan motors.

The automatic control system is also switched off from a remote panel. At the same time, the magnetic starters of the pump and fan motors are de-energized, the air intake valves and the valve are closed K2 on the heat carrier.

Air conditioning systems (ACS) are designed to create and automatically maintain the necessary air parameters in the premises (temperature, relative humidity, cleanliness, speed, etc.). Depending on the purpose, ACS are divided into technological ones, which ensure the state of the air environment that meets the requirements of a particular technological process, and comfortable ones, which create favorable conditions for a person. Depending on the design, air conditioners are divided into sectional and modular, and according to the equipment for generating heat and cold, they are divided into autonomous and non-autonomous. Autonomous air conditioners are supplied from the outside only with electricity. For the operation of non-autonomous air conditioners, it is necessary to supply heat and coolant from the outside, as well as electricity to drive the motors of fans and pumps.

Let us first consider the basic principles of automating a comfort air conditioning unit designed to maintain a given temperature and humidity in a room (Fig. 8.5).

For winter conditions air is processed according to the following scheme. Outside air is first heated in the heat exchanger U from the point H 3 to point U 3 , and then in the air heater of the first stage from point U 3 to the value / k. As a result of adiabatic humidification at a constant enthalpy, the air acquires parameters corresponding to the point K g In the air heater of the second stage, the air is heated up to point R 3 and is supplied to the room.

As the enthalpy of the outside air increases, its heating in the first stage air heater decreases, and when the enthalpy is reached 1 TO heating must be turned off. A transitional regime begins, which is characterized by a constant internal temperature / 3 and varies depending on the enthalpy of the outdoor air and the relative humidity inside the room.

Based on the conditions of comfort, fluctuations in relative humidity within 40-60% are permissible. When the enthalpy of outdoor air is higher than / n in the manned room, it is advisable

Rice. 8.5.

a - technology system SKKV; b - air treatment processes

in /-b diagram

maintain the maximum relative humidity (up to 60%) under comfortable conditions, while allowing significant fluctuations in the internal temperature. Since fluctuations in the internal temperature are associated with a change in the enthalpy of the outside air, a certain "dynamic" climate is created in warm time, characterized by the best conditions for human well-being than static at constant temperature. At the same time, some savings in cold consumption are provided. With an enthalpy of outside air / n, only adiabatic humidification is provided. At this time, the air heater of the second stage is affected by a relative humidity sensor cp installed in the room, with the help of which, when the humidity deviates to big side the flow of coolant to the air heater increases. The dotted line in fig. 8.5 (from Hp to /l) indicates that the sensor must be set to 57-58% in order to avoid an increase in the value of f over 60%. This is due to the inadmissibility of a higher relative humidity and the desire to maintain the set operating temperature difference between the indoor and supply air.

The summer mode of operation of the air conditioning system begins when the outside air reaches enthalpy / l. At this time, cold water supply to the irrigation chamber is required to maintain air parameters. K l. For this purpose, a temperature sensor is installed behind the irrigation chamber, with the help of which, as the temperature rises, the supply of cold water to the chamber increases. Since the air temperature behind the nozzle chamber is not the same, moisture droplets can be carried out and get on the temperature meter. In addition, taking into account the negative effect of radiant heat from the second heating air heater, it is advisable to carry out the regulation according to the signals of the temperature sensor installed in the room. The advantages of this method include the fact that it also takes into account the heat storage capacity of the room. The temperature meter installed in the room is adjusted to the temperature value determined by the point t l, and affects the supply of cold water to the irrigation chamber.

The automation system built on the basis of the scheme of such air treatment is shown in fig. 8.6. AT winter period for irrigation

Rice. 8.6.

air conditioning

With the help of a proportional controller, the set temperature is maintained by the body chamber (pos. 1). The meter, set to the temperature / p 3 , acts on the actuator of the regulating body on the coolant return pipeline to the air heater of the first heating gearbox. The irrigation chamber provides adiabatic humidification of the outside air up to 90-95%. As the enthalpy of the outside air increases, its heating decreases, and at enthalpy / k, the first heating is turned off.

The indoor air temperature is controlled by a two-position regulator (pos. 2). Temperature sensor installed in the room and configured to maintain the temperature (3 , acts through a prohibition-allowing device (pos. 3) to the air heater of the gearbox of the second heating. A disable device is included in the circuit to switch indoor temperature control to relative humidity control. This switchover takes place when the relative humidity in the room approaches 60%. At this moment, the air temperature behind the irrigation chamber will rise to the value / p p. The signal from this sensor is sent to the prohibition-permissive device, which switches the indoor temperature sensor to the relative humidity sensor.

In warm weather indoors, using a proportional regulator (pos. 6) constant relative humidity is maintained at varying temperatures. Humidity sensor, as in winter time, through an intermediate relay RP and a prohibition-permissive device acts on the air heater of the second stage. When the relative humidity rises above 60%, the second heater is switched on and the temperature reaches a value at which the relative humidity becomes less than 60% and corresponds to a certain enthalpy of the outside air.

Summer mode, which requires the use of cold water, occurs at an indoor temperature corresponding to the average summer comfort. At this moment, the second temperature sensor, set to 1 L. The temperature regulator (pos. 5) affects the supply of cold water to the irrigation chamber. In the room, two parameters are stabilized at once: temperature and relative humidity. Two regulators act on different regulatory bodies at once, which allows maintaining relative humidity with an accuracy of ± 5% and consuming a minimum of cold. Improving the accuracy of stabilization of microclimate parameters can also be achieved by synthesis of stabilization with correction for deviations from the specified temperature and relative humidity in the room. This is ensured by the transition from single-circuit to double-circuit cascade stabilization systems, which, in essence, should be the main systems for controlling temperature and air humidity.

The operation of cascade systems is based on the regulation of not one, but two regulators, and the regulator that controls the deviation of the main regulated variable from the set value does not act on the regulatory body of the object, but on the auxiliary regulator setpoint. This controller maintains at a given level some auxiliary value of the intermediate point of the regulated object. Since the inertia of the controlled section of the first control loop is negligible, relatively high speed can be achieved in this loop. The first circuit is called stabilizing, the second - corrective. The functional diagram of the cascade system for direct-flow SCR is shown in fig. 8.7.

The first system ensures stabilization of the air temperature after the air heater of the second heating with correction

Rice. 8.7.

air conditioning process

according to the air temperature in the control object (room) by changing the coolant flow in the air heater (TC 2 controller). The corrective action is carried out using the corrective controller TS 2 . Thus, the air temperature control system after the second heating air heater includes an air temperature control circuit by changing the coolant flow rate and a correction circuit that changes the TS 2 controller setting depending on the change in the air temperature in the room.

The second stabilization system includes a dew point temperature sensor installed after the spray chamber, and a TC regulator that sequentially controls the actuators of the spray chamber valves, the first heating air heater, and the mixing and regulating air valves of the outside and recirculation air.

The corrective action on the TC controller is carried out with the help of the MS humidity controller, the sensor of which is installed in the room.

AT last years in the implementation of the considered principles of automation of air conditioning systems, microprocessor controllers are increasingly used.

Today, ventilation and air conditioning systems are present in all newly built buildings. They are laid at the stage of project development, because they provide: ventilation - the outflow of polluted air and the supply of fresh air, air conditioning - provides comfortable conditions presence of people in the premises, namely, it leads the humidity and temperature to normal values. Since both systems are quite complex, automation is being developed for them, which monitors the parameters of their work. In this article, we will understand what the automation of air conditioning and ventilation systems is.

Why do you need

First, it should be noted that the following are considered normal indoor conditions:

temperature + 20-24C;
humidity - 40-65%;
the speed of air movement is 1 m/s.

To control these parameters, it is necessary to carefully calculate and assemble the automation of heating, ventilation and air conditioning systems. At the same time, the project immediately determines the places for their installation and functional purpose. Very often in buildings with large dimensions and many rooms, an air conditioning system is used, which includes several subsystems. And, as practice shows, all subsystems work individually. In order to follow all of them, an automatic air conditioning system is being installed.

It must be understood that the air conditioning and ventilation system is quite expensive in terms of electricity consumption. Therefore, it is very important to correctly configure the automation that provides control over air conditioners and fans. And if with latest problems does not occur, because they are tuned to a certain rotation speed, which will be constant almost all the time, then for air conditioners the setting is more complicated.

After all, their work mainly depends on the humidity and temperature of the air inside the premises. These two values are not constant. This means that the automation will have to be configured so that it first of all controls these two parameters, and then transmits a signal to the air conditioners. And they will work in terms of power with an increase, then with a decrease. And here the setting can be made so that the conditions inside the premises are normal, and the power consumption of the air conditioners is not maximum.

The dispatching of ventilation and air conditioning systems is responsible for this. Namely, several devices that process data and transmit them to the equipment. At the same time, a strict sequence of algorithms is maintained, which are programmed individually for each type of equipment.

Automation of ventilation and air conditioning

There are three types of ventilation and air conditioning automation systems: partial, complex and complete. Most often, the first two are used. Automation itself consists of several blocks that control different processes:

sensors or, as specialists call them, primary converters;
secondary;
regulators are automatic;
actuators, in some schemes control devices are used;
electrical equipment, with the help of which the electric drives of fans and air conditioners are regulated.

Basically, all these mechanisms and devices that are part of industrial automation are standard. That is, they are mass-produced according to GOSTs. But there are some of them that are produced in small batches and are intended specifically for air conditioning systems, for heating and ventilation systems. For example, sensors for controlling air humidity or temperature controllers of the brand T-8 or T-48.

Usually, all devices that show the parameters of the indoor conditions are installed in a special separate shield. At the same time, it is necessary to understand that the more subsystems in the building, the more shields have to be installed. This complicates the monitoring of parameters that must be periodically removed. To simplify this process, today in the branched air conditioning and ventilation systems a control panel is organized, behind which the operator sits. One person is in complete control of the entire process. At the same time, with the help of the Internet, the problem of signaling and the ability to control all parameters at a distance is solved. That is, an SMS with data on all ongoing processes can come to the phone.

As for the sensors, it is very important to correctly place them in the rooms with a certain frequency of placement. It is these small devices that begin to respond to changes in air parameters. It is they who give impetus to the beginning of the change in the operation of the equipment. But HVAC automation systems do more than just monitor the conditions inside a building. Sensors are installed in each duct, which monitor whether something has got inside. After all, even a small foreign object can get into the equipment and disable it. This is also very important for dampers that shut off the air supply and exhaust.

Any automation includes a warning and alarm system. Here it is standard: sound and light.

Dispatching ventilation and air conditioning

Dispatching is the collection of signals from sensors and, based on them, the management of all processes. The main functions of scheduling ventilation and air conditioning are:

Indexing of incoming signals from sensors, their processing and configuration.
Sending a signal to the dispatcher if deviations from the specified parameters occurred in the system or an unusual or emergency situation occurred.
If necessary, the operation of the entire circuit is transferred to emergency mode.
If a fire breaks out in a building, the smoke extraction system is activated.
Air parameters are strictly monitored and maintained throughout the operation of the equipment.
If necessary, adjust the set parameters.
During low load hours, ventilation and air conditioning systems are switched to the mode of saving electricity and other types of energy carriers (steam, hot water).
Data is processed at the time of activation or deactivation.

Depending on the customer's requirements for air conditioning, automation can be carried out using freely controlled devices (controllers) or with the addition of so-called software and hardware systems. The second option is more expensive, but it makes it possible to combine all control levers in one control point.

However, it should be understood that situations in large buildings with several subsystems can be different. Therefore, air conditioning and ventilation is divided into modules in terms of providing dispatching. And each module can work autonomously in the event of an emergency.

Dispatch capabilities:

it is possible to organize the management of a large number of modules, which, as necessary, are connected in parallel;
setting up the collection of data that the user needs;
the ability to transfer data to other computers;
telephone and computer networks are controlled;
automation of data transfer processes from the lower levels to the control panel;
data transfer to the phone.

Controllers for automation and dispatching

In principle, it should be noted that the technological scheme of air conditioning and ventilation of the building, which includes the controller, is standard, or rather basic. It can be modified to suit your requirements with an add-on. For example, you can change the indoor temperature control not through a duct sensor installed in the ducts of the exhaust ventilation system, but through a cascade sensor, which is installed directly in the room itself. Or you can configure the heating of the blinds in the air conditioning, which open or close the openings.

That is, the dispatching of ventilation and air conditioning systems, taking into account the installed controllers, can be developed according to different schemes. And at the same time, you can choose such a technological chain that will be beneficial specifically for a certain type of building where different requirements to individual rooms.

Home Automation

Today, the term “smart home” is increasingly heard. In fact, this is the automation of control over all networks that ensure the normal life of a person in own house. Of course, this is an extensive network, the tasks of which include:

external and internal security (the latter is the tracking of employees performing domestic work in the house);
control and monitoring emergencies: leaking gas, cold or hot water;
creating a favorable indoor climate, and this applies to air conditioning, heating and ventilation.

At the same time, dispatching strictly controls all work. engineering networks. And if there is a need to change any parameter, there is no need to run around the floors to the automation panels to make the adjustment. " Smart House» is supplied with a separately installed mini-remote control or a mini-unit, through which the regulation and setting of the required modes is carried out.

Most importantly, all automation is tied to dispatching from controllers installed in it. That is, the technological scheme here is exactly the same as at any facility where there are modular air conditioning and ventilation schemes.