Question 1

What are building automation and control systems?

Accepted Answer

Building automation and control systems (BACS) use various technologies and protocols to monitor, control and optimize the mechanical, electrical and lighting systems in a building. These systems can be used to control HVAC, lighting, security, fire protection and other building systems and they can be integrated with engineered systems such as energy management and access control systems. They are often used in commercial and industrial buildings, as well as in multidwelling residential buildings. The goal of these systems is to improve energy efficiency, comfort and safety, while also reducing operating costs.

Question 2

What do building automation systems do?

Accepted Answer

The main functions of a building automation system (BAS) include:

HVAC control: BAS can control the heating, ventilation and air conditioning systems in a building, ensuring that the temperature and humidity levels are maintained within a comfortable range.
Lighting control: A BAS can control the lighting in a building, turning lights on and off as needed and adjusting the brightness levels to optimize energy efficiency.
Security and fire protection: A BAS can integrate with security and fire protection systems, such as access control and fire alarms, to ensure the safety of the building's occupants.
Energy management: A BAS can monitor energy usage and identify opportunities for energy savings.
Remote monitoring and control: A BAS can be accessed remotely to monitor the building's systems and make adjustments as needed.
Scheduling: BAS can be scheduled to perform certain actions such as turning off lights when not in use or adjusting temperature according to occupancy schedule.

Overall, building automation systems aim to improve the energy efficiency, comfort and safety of the building, while reducing operating costs.

Question 3

What is the most common building automation control strategy?

Accepted Answer

The most common building automation control strategy is the use of feedback control loops. This strategy involves constantly monitoring the conditions in a building, such as temperature and humidity and comparing them to a setpoint. If the conditions deviate from the setpoint, the building automation system (BAS) will adjust the mechanical and electrical systems to bring the conditions back to the setpoint.

For example, in the case of HVAC control, if the temperature in a room is too high, the BAS will turn on the air conditioning to cool the room down. Once the temperature reaches the setpoint, the air conditioning will turn off. This process is known as a ""closed-loop"" control, as the system is constantly monitoring the conditions and making adjustments based on the feedback it receives.

This type of control strategy is widely used and adopted due to its efficiency and flexibility in handling multiple variables and achieving the desired results.

However, depending on the complexity and specific requirements of the building, other control strategies such as predictive control or model predictive control may also be used.

Question 4

What is the difference between BAS and BMS?

Accepted Answer

Building automation system (BAS) and building management system (BMS) are related but different systems.

A BAS is a computer-based control system installed in buildings that controls and monitors the mechanical and electrical equipment such as HVAC, lighting and security. The main focus of a BAS is to improve the energy efficiency, comfort and safety of the building, while reducing operating costs.

A BMS, on the other hand, is a more comprehensive system that integrates all the subsystems of a building and provides a single point of control and monitoring. A BMS also known as building automation and control system (BACS) is a centralized system that controls and monitors all of the building's systems, including HVAC, lighting, security, fire protection and other systems. BMS also provides a user interface that allows building operators to view the status of all systems and make adjustments as needed.

In short, a building automation system focuses on the mechanical and electrical systems of a building, while a building management system is a more comprehensive system that integrates all subsystems of a building and provides a single point of control and monitoring.

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