Modern large shopping centers, business buildings, as well as partnerships of homeowners and private property need constant technical control. Management of ventilation, water supply, electricity supply, it is impossible to carry out without the help of special computer programs. They automatically control and change the operation of mechanisms, and in case of possible malfunctions and in emergency situations, the system gives an alarm signal. This building management system (Building Management System) is called the "dispatch system." In more detail about how it is designed and installed, we will tell in our article.
Dispatching system: principles of work
Modern control rooms are equipped with control computers for engineering systems. They are switched with controllers in server and frequency converters on installed engineering equipment. Dispatch and automation systems are designed to make it easier to find building equipment.
Using a computer, the dispatcher at the enterprise, and the owner or staff in a private house, monitors changes in the supply air temperature, pressure drops in the pipes and controls other parameters of various equipment.
Remote control
You can remotely control ventilation air handling units. By changing the percentage of opening of the refrigerant valve, you can affect the temperature of the supply air. The building scheduling system remotely monitors the following objects:
- Individual heat point.
- Main power distribution switchgear and introductory switchgears.
- Indoor and outdoor lighting.
- Gas supply.
- Supply and exhaust ventilation units.
- Air conditioners and fan coils.
- Water supply and sewerage.
- Drainage system (drainage pits and storm sewers).
- Fire alarm and air fire.
- Sensors of gas contamination of parking spaces.
- Access control to the building.
- Elevator and escalator equipment.
Initial preparation and commissioning
The installation of the described equipment should be considered at the construction stage of the building. Dispatching systems are designed by special contractors.
The project should include cable channels connecting all equipment for communication with the server. Signals from chastotniks, which are located on installations, pumps, power equipment, and other systems, come to the server blocks via cable.
The server room is supposed to be placed in a separate, well-ventilated room, in order to cool the power supplies and fans installed inside the server racks.
Installation work
Dispatching systems are usually installed by specially hired contractors. As a rule, they have their own finished projects, but they can also work on customer projects. Maintenance of the dispatch system at the stage of warranty service is carried out by the contractor who installed this equipment.
After the warranty period of service has elapsed, it is possible to control the work by the duty team. Typically, a low-voltage engineer is involved in maintaining the system. Different teams have their own established schedule, and the efficiency of low-voltage equipment work depends on this.
Control system internal filling
There are several computer programs that monitor the equipment installed at the facility. Not so long ago, Honeywell and Johnson Controls were popular. Nowadays, Siemens, Orion and other, less common programs, as well as modified Honeywell and Johnson Controls are usually installed at new facilities.
The object dispatching system requires constant monitoring and updating. Typically, all systems are installed with a long warranty period, and subsequently, at the end of the warranty period, the same contracting companies fulfill the commissioning and maintenance obligations.
For elevator equipment, everything is set depending on which company-contractor is installing and maintaining elevator dispatch systems (Kone-Lift, ThyssenKrupp AG, Otis and others).
How the fire system works
Automation is also installed on fire fighting equipment. It is triggered by the smoke of fire sensors and gives an alarm to the control room. The dispatcher on the monitor sees the location of the sensor and reports the incident on duty shift.
If two smoke detectors are triggered, then an alarm message about the immediate evacuation will sound to the whole building. In this case, the air inlet system in the elevator shafts will turn on. The elevators will automatically go down to the first floor and open the doors without responding to calls and orders.
How is automation controlled?
The equipment installed in the building houses sensors and instrumentation. They collect information about the condition of the equipment and interact with controllers that transmit a signal to the automation system and the computer installed in the control room. The dispatcher operator on the working monitor sees the status of the system and, if necessary, controls the settings.
The ventilation automation adjusts the set parameters according to the room temperature settings. If it is a supply and exhaust system equipped with a heat exchanger, heat exchanger and a cold circuit, the automation maintains the desired temperature by closing or opening the cold (hot) water valve or increasing the speed of the heat exchanger. The dispatcher observes all these changes on the monitor screen in the control room.
In the cold season, when the outdoor temperature drops below twenty degrees Celsius, it is possible to transfer the units to the dispatcher or duty personnel in manual mode to prevent freezing of the heat exchanger.
By setting the necessary parameters on his control panel (computer), the dispatcher monitors the changes and the process of the installations. Usually, leading engineers, taking care of the normal operation of the equipment, place the schedule and operating schedule of ventilation units on a special stand or in the dispatcher's operational journal. According to him, the dispatching system controls the processes of heat transfer and cold supply.
Security systems
When referring to dispatch control systems, one should not forget about special dispatch systems for the security structure. Abbreviated as ACS (access control system). It does not connect to the ventilation control system and other engineering equipment and is equipped with a special computer.
The control computer receives signals from all electromagnetic locks, turnstiles and other electronic readers, including a car entry-exit control system from the parking lot. All passes issued to employees and staff have numbers by which it is possible to determine at what time this employee passed through a turnstile or door equipped with a magnetic lock. All these data, also transmitted by magnetic sensors, are sent to a special access control dispatcher computer.
The remote access control system is connected to the fire safety engineering system. In case of emergency, it automatically unlocks the doors of all emergency exits.
An important place in the work of building management systems is occupied by the uninterruptible power supply server. In the event of a voltage drop, it will save it on the control panel and will turn off the system without data loss.
Where use building management systems
Not a single modern business center is complete without building management systems. Even ordinary lighting in buildings is switched on through a dispatch system. In addition, security centers play an important role in business centers. Therefore, access control systems are also installed. They provide the work of storage facilities, as well as entry and exit from parking spaces. The same applies to elevator and escalator equipment.
In any buildings, the installation of dispatch systems facilitates the work of on-duty personnel and allows you to save energy resources, creating comfortable conditions in the premises