Last edited 07 Apr 2020

Building automation

1 Introduction
2 Benefits
3 Components
4 Potential issues
5 Related articles on Designing Buildings Wiki

[edit] Introduction

Building automation typically involves the automatic control of heating, ventilation and air conditioning systems, lighting, access control, energy management, fire alarms and other building services. This may involve the use of an electronic building management system (BMS). Commercial, industrial and residential buildings fitted with such systems are often called ‘smart buildings’ or intelligent buildings’.

Most commercial buildings constructed after 2000 are fitted with some form of Building automation systems (BAS). These are typically distributed control systems in which a variety of electronic devices monitor and control mechanical devices which in turn can be instructed to alter the state of an environment at any particular time or at predetermined set times. The user interface – whether for homeowners or building maintenance personnel – displays the system status, detects possible problems and makes necessary adjustments. Building facilities managers and home owners can input their required comfort settings and these will be maintained until changed.

This may include maintaining room temperatures within a specific range at certain times; switching lights on and off depending on occupancy; lowering the energy consumption of a building’s water circulation pumps through variable frequency drives; monitoring system performance and, in the event of impending malfunctions, providing notifications via email, text message, mobile voice call and/or an audible alarm to the end user.

[edit] Benefits

Compared to a non-controlled building the benefits of a BAS can include:

Enhanced occupant comfort and productivity.
Improved operation of systems.
Increased energy efficiency and so lower emissions.
Better connectivity and monitoring of systems.
Improved safety.
Maintenance staff can be more efficient and productive.
Lower maintenance costs.
Time savings.

[edit] Components

A building automation system’s hardware typically comprises:

Servers – which run the BAS software through desktop or rack-mounted PCs to collect and serve data.
Controllers – small, programmable control systems to control inputs and outputs to air handling, heating and other systems (based on inputs received).
Field buses – the way field controllers communicate with supervisory devices.
Supervisory devices – usually installed in dedicated devices and typically with an Ethernet NIC and a field trunk port.
Inputs – signals from devices such as temperature or pressure sensors.
Outputs – BAS controller sends a command as an output to say, a relay or actuating device etc.

Software can include:

Databases – store information, eg alarms, trends, reports, schedules etc.
Configuration software – configures servers, other devices and field controllers.
User interfaces (UI) – installing or downloading applications, using web browsers to access the BAS.

[edit] Potential issues

Cyber security can be a problem. A BAS may not be secure and can feature vulnerabilities which can be exploited by hackers. It is possible to improve the security of a BAS by taking steps such as: