Building Automation Systems

What is a building automation system (BAS)?
Building automation systems (BAS) manage and automate a building’s lighting, HVAC, power, safety, access control, and security systems. BASs optimize efficiency and reduce waste in green building design and help with carbon offset and sustainability. BASs may include hardware controllers to coordinate subsystems operation, smart devices for decentralized coordination, or PC-based software for automation and control. Visualization and data acquisition components boost overall performance.
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How does building automation work?

A building automation system (BAS) automates various building functions such as lighting, heating, cooling, and access control. The BAS is often a system of systems providing supervisory control, data acquisition, and automation within and between a building’s mechanical, electrical, water/wastewater, and other systems.

Five essential components of building automation

Controllers

Controllers connect to electrical, mechanical, and other systems and sensors for automated control, monitoring, and data acquisition. A single BAS may include multiple controllers. 

Controllers connect to electrical, mechanical, and other systems and sensors for automated control, monitoring, and data acquisition. A single BAS may include multiple controllers. 

Output Devices

Output devices refer to components of a BAS that receive signals and perform a physical action such as actuators to adjust air dampers, relays to engage and disengage locks, and switches to turn lights on and off.

Output devices refer to components of a BAS that receive signals and perform a physical action such as actuators to adjust air dampers, relays to engage and disengage locks, and switches to turn lights on and off.

Communication Protocols

The BAS may use a variety of communication protocols such as Modbus RTU over RS-485, Modbus RTU over Ethernet, Modbus TCP/IP, BACnet/IP, and BACnet MS/TP. Other commonly used protocols are LonWorks and KNX.

The BAS may use a variety of communication protocols such as Modbus RTU over RS-485, Modbus RTU over Ethernet, Modbus TCP/IP, BACnet/IP, and BACnet MS/TP. Other commonly used protocols are LonWorks and KNX.

Dashboard/User Interface

Building automation systems often include one or more dashboards with a view of the overall system and detailed information about its included individual subsystems and components.

Building automation systems often include one or more dashboards with a view of the overall system and detailed information about its included individual subsystems and components.

Understanding the building automation architecture

Server/application layer

Supervisory layer

Field controller layer

Input/output layer

Benefits of building automation

Lower operational costs

Building automation systems reduce building operational costs through advanced monitoring and automation capabilities. Components can be monitored remotely to avoid local management requirements, and tasks, such as controlling lights, faucets, ventilation, heating, and cooling, can be automated.

Lower energy costs

Automation ensures that building systems operate only when necessary, significantly lowering energy costs for high-demand utilities such as lighting, cooling, and heating. Systems can be managed by precise scheduling and real-time adjustments based on data from environmental sensors and manual inputs at control points.

Increased efficiency

Building automation systems increase the efficiency of building equipment, such as HVAC, by limiting unnecessary demand and better determining optimal target setpoints through real-time data from sensors and local interfaces.

Systems controlled by building automation

HVAC systems use air conditioners, furnaces, ducts, dampers, and thermostats to control the environment inside buildings.

Default schedules often manage lighting system interior and exterior components and can be overridden by local control points.

BAS security and access control components manage entry and movement, usually based on time of day and specific credentials.

Automated switchgear aids in power recovery events, while monitoring electrical systems for anomalies ensures efficiency.

Kepware’s Building Automation Suite

Kepware’s Building Automation Suite is the leading communication software to facilitate the management of building lighting, HVAC, power, safety, and security. The Suite includes drivers for industry-standard protocols BACnet/IP and Modbus, as well as System Monitor, User-Configurable (U-CON), and Custom Interface drivers for custom protocol support and DIY driver development.
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Frequently asked questions

 

Evolution of smart buildings: Is building automation new?

Building automation is not a new concept, as it has been around for several decades. However, with advancements in technology, the evolution of smart buildings has seen significant progress in recent years. Smart buildings now use innovative systems and sensors to optimize energy efficiency, improve occupant comfort, and enhance overall building performance. This evolution has been driven by the increasing demand for sustainable and efficient building solutions in a rapidly changing world.

What is the difference between a BMS and a BAS?

A building management system (BMS) is typically more focused on controlling and monitoring building systems, such as HVAC, lighting, and security, through a centralized platform. In contrast, a building automation system (BAS) is more comprehensive and includes additional features, such as data analysis, optimization, and integration, with other building systems to improve efficiency and comfort levels.

What can a building automation system (BAS) do?

A BAS can control and monitor various building systems such as heating, ventilation, air conditioning, lighting, and security. It can help improve energy efficiency by optimizing systems based on occupancy, weather conditions, and other factors. Additionally, it can provide real-time data and analytics to help building managers make informed decisions about maintenance and operation. By centralizing control and monitoring, a building automation system can also improve overall comfort and safety for building occupants. Overall, a BAS can streamline operations, reduce costs, and create a more sustainable and comfortable environment.

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