Building management systems

Building Automation Systems - their importance and fuction

The current user standard of modern buildings:
energy efficiency, smart / inteligent control management, flexibility, comfort and safety

Introduction into the theory

The demand of investors and tenants for the intelligent building management systems and in particular their energy efficiency continue to increase. The building owners or landlords require comfort, security, safety, control management system, energy consumption monitoring and the highest level of possible flexibility.

Modernly equipped building in terms of Building Automation Management (sometimes referred to as the "Intelligent Building") is a comprehensive integrated system complex, in which the systems are integrated / connected in one communication / visualization platform and the monitored and controlled technologies are able to communicate with each other. The heart of the building is the Building Automation System sometimes also called as "Control System" or "BMS" - Building Management System.

The building automation system mainly provides the control of connected technologies (HVAC systems) such as heating, cooling, ventilation, aircondition, refrigeration, etc.

Selection of main basic functions of the building management system:

  • the control of actuators (eg. closing of valves, dampers, etc.)
  • the data collection from connected systems (eg. monitoring of valve positions, energy metering data, etc.)
  • scanning physical values from sensors (eg. temperature, pressure, etc.)
  • surveying variations from measured values and control outputs (eg. comparing the actual and the desired room temperature)
  • enter and set commands for controlled technologies (eg. response to unexpected or critical operating modes)
  • data collection and monitoring of varied values (eg. for subsequent data analysis and control management decisions)
  • real time control management of technologies (the time value for all technologies is the same)
  • data transfer to other systems (eg. integration of lighting control management, control of blinds, elevators, access control systems, etc.)
  • data archiving and data visualization for operators and maintenance staff (that is a particular feature of control dispatching center)

Importance of control dispatching center (sometimes also called as SCADA system or graphical visualization system)

In our area there is a deep-rooted myth that the control management of all systems take place in the Control Dispatching Centre. This in most cases is not true. The control management of processes (ie regulation) operate on the level of the contollers (in other names: DDC controller, PLC, etc.) therefore they run on the subsidary level of the dispatching control center. Control dispatching center is only a sort of an "access window to the system and data storage."

Main role of the dispatching control center:

  • the collection and archiving of data and readings (eg. some data can result from automated calculations)
  • visualization of readings and values (MMI - Man Machine Interface)

Control center components:

1) Hardware components:

  • regular: a computer with standard accessories, such as a printer, a hard disk, a monitor etc.
  • additional: a laptop, an iPad, a tablet, etc.

2) Software components:

  • software operating system (frequently used type of operating system - MS Windows - is a standard part of each computer)
  • firmware: software operating system - software application for visualizations
  • user software: specifically programmed application software (eg. manufactured and supplied by a company that executes a given project)

The control system very often provides connection and data transmission between other systems or building's technologies such as access control system, alarm system, security, CCTV system, lighting control system, shutters and blinds control, elevator control, UPS, power supply backup for the run of essential technologies, engine control through frequency drivers, renewable energy sources, heat recovery units and IT infrastructure and power cable wiring, etc.

All the important information from these systems are then stored in one place (the control center) and are processed into simple outputs or into report protocols consisting value readings and the system status. Control management systems for intelligent buildings respond automatically to any changes of the system status and the high-quality control management systems have automatic or programmed optimization software functions. After the evaluation of obtained data we can select the appropriate mode of operation for the building according to the specific needs and requirements with a subsequent optimization for an energy consumption.

Today, when we all are being pushed towards the energy savings, it is well recommended to have a good control management system in a building for measurement of power, heat / cold, water or gas consumptions.
These days it is also possible to use Building automation system to control the energy consumption ie. control of turn on and off mode of unnecessary electrical loads (ie. properly define and distribute the energy consumption diagram), and in particular to control lighting of the building and the rooms.

An essential part of a modern intelligent building is the use of new technologies and procedures, such as freecooling, cold accumulation into the building envelope or the use of passive systems for buildings such as modern insulating materials, high-quality facades, control management of open and close mode of windows, and collection and use of rainwater. It is also very important to pay attention to the impact of people's behavior, to the design layout of the building and at the last to the proper use of the building itself.

Importance of Building automation system for service:

Seldom we realize that the economic and operating life of a building is more than 50 years and during the entire life cycle of a building there is a dire need to monitor and manage the building's technologies. No intelligent installation could possibly and properly work or run without a regular servicing and maintenance by a professional service satff. This is the only way how to achieve high-quality, optimal and economical run and operation of a building.