"Building automation" can also refer to Build automation, the practice of programmatically compiling software programs.

Building automation is a programmed, computerized, "intelligent" network of electronic devices that monitor and control the mechanical and lighting systems in a building. The intent is to create an intelligent building and reduce energy and maintenance costs. Build Automation is the act of scripting or automating the process of turning computer source code into binary code. ... A compiler is a computer program that translates a computer program written in one computer language (called the source language) into an equivalent program written in another computer language (called the output or the target language). ... A computer program (often simply called a program) is an example of computer software that prescribes the actions (computations) that are to be carried out by a computer. ... Light control computerized system Home automation (also called domotics) is a field within building automation, specializing in the specific automation requirements of private homes and in the application of automation techniques for the comfort and security of its residents. ... This article or section is in need of attention from an expert on the subject. ... To meet Wikipedias quality standards, this article or section may require cleanup. ...

Image File history File links This is a lossless scalable vector image. ...

Infrastructure

Controller

The controller is normally one or more application specific controllers, often with less complex programming. These controllers come in a wide range of sizes and capabilities to control devices that are common in buildings. Usually the primary and secondary buses are chosen based on what the controllers provide.

Most PLCs provide general purpose feedback loops, as well as digital circuits. A Proportional-Integral-Derivative controller is a standard feedback loop component in industrial control applications. ... Digital circuits are electric circuits based on a number of discrete voltage levels. ...

Occupancy sensors

Occupancy is usually based on time of day schedules. Override is possible through different means. Some buildings can sense occupancy in their internal spaces by an override switch or sensor.

Lighting

Lighting can be turned on and off with a building automation system based on time of day, or the occupancy sensors and timers. One typical example is to turn the lights in a space on for a half hour since the last motion was sensed. A photocell placed outside a building can sense darkness, and the time of day, and modulate lights in outer offices and the parking lot. Strand Lighting 300 Series Control Console An Express 48/96 memory console by Electronic Theatre Controls capable of controlling both normal stage lighting instruments as well as intelligent lighting. ...

Air handlers

Most air handlers mix return and outside air so less temperature change is needed. This can save money by using less chilled or heated water (not all AHUs use chilled/hot water circuits). Some external air is needed to keep the building's air healthy.

Analog or digital temperature sensors may be placed in the space or room, the return and supply air ducts, and sometimes the external air. Actuators are placed on the hot and chilled water valves, the outside air and return air dampers. The supply fan (and return if applicable) is started and stopped based on either time of day, temperatures, building pressures or a combination.

Constant Volume Air-Handling Units

The less efficient type of air-handler is a "Constant Volume Air Handling Unit," or CAV. The fans in CAVs do not have variable-speed controls. Instead, CAVs open and close dampers and water-supply valves to maintain temperatures in the building's spaces. They heat or cool the spaces by opening or closing chilled or hot water valves that feed their internal heat exchangers. Generally one CAV serves several spaces, but large buildings may have many CAVs. A zone damper is a specific type of damper used to control the flow of air in an HVAC heating or cooling system. ... A heat exchanger is a device built for efficient heat transfer from one fluid to another, whether the fluids are separated by a solid wall so that they never mix, or the fluids are directly contacted. ...

Variable Volume Air-Handling Units

A more efficient unit is a "Variable air volume (VAV) Air-Handling Unit," or VAV. VAVs supply pressurized air to VAV boxes, usually one box per room or area. A VAV air handler can change the pressure to the VAV boxes by changing the speed of a fan or blower with a variable frequency drive or (less efficiently) by moving inlet guide vanes to a fixed-speed fan. The amount of air is determined by the needs of the spaces served by the VAV boxes. A variable air volume (VAV) device is a computer-controlled zone damper used in HVAC systems to vary the flow of air through ductwork. ... It has been suggested that this article be split into multiple articles accessible from a disambiguation page. ... Blower may refer to the Blower, a fish of the Atlantic coast of the United States and the West Indies USS Blower, a Balao class submarine of the United States Navy an old-fashioned slang term for the Telephone, especially in the UK a ducted fan, usually part of some... Small Variable Frequency Drive (VFD) A Variable Frequency Drive (sometimes abbreviated VFD) is system for controlling the rotational speed of an alternating current (AC) electric motor by controlling the frequency of the electrical power supplied to the motor. ...

Each VAV box supply air to a small space, like an office. Each box has a damper that is opened or closed based on how much heating or cooling is required in its space. The more boxes are open, the more air is required, and a greater amount of air is supplied by the VAV air-handling unit.

Some VAV boxes also have hot water valves and an internal heat exchanger. The valves for hot and cold water are opened or closed based on the heat demand for the spaces it is supplying. These heated VAV boxes are sometimes used on the perimeter only and the interior zones are cooling only.

A minimum and maximum CFM must be set on VAV boxes to assure adaquate ventilation and proper air balance.

VAV Hybrid Systems

Another variation is a hybrid between VAV and CAV systems. In this system, the interior zones operate as in a VAV system. The outer zones differ in that the heating is supplied by a heating fan in a central location usually with a heating coil fed by the building boiler. The heated air is ducted to the exterior dual duct mixing boxes and dampers controlled by the zone thermostat calling for either cooled or heated air as needed.

Central plant

A central plant is needed to supply the air-handling units with water. It may supply a chilled water system, hot water system and a condenser water system, as well as transformers and auxiliary power unit for emergency power. If well managed, these can often help each other. For example, some plants generate electric power at period with peak demand, using a gas turbine, and then use the turbine's hot exhaust to heat water or power an absorptive chiller. A hot water heater is an appliance for heating water above its ambient temperature. ... Figure 1:Three-phase pole-mounted step-down transformer. ... The APU exhaust at the tail end of an Airbus A380 An auxiliary power unit (APU) is a device on a vehicle whose purpose is to provide energy for functions other than propulsion. ... This article needs to be wikified. ...

Chilled water system

Chilled water is often used to cool a building's air and equipment. The chilled water system will have chiller(s) and pumps. Analog temperature sensors measure the chilled water supply and return lines. The chiller(s) are sequenced on and off to chill the chilled water supply. York International water-cooled chiller. ... An electrically driven pump (electropump) for waterworks near the Hengsteysee, Germany. ...

Condenser water system

Cooling tower(s) and pumps are used to supply cool condenser water to the chillers. The condenser water supply to the chillers has to be constant so, speed drives are commonly used on the cooling tower fans to control temperature. Proper cooling tower temperature assures the proper refrigerant head pressure in the chiller. The cooling tower set point used depends upon the refrigerant being used. Analog temperature sensors measure the condenser water supply and return lines. Image 1: Natural draft wet cooling towers at Didcot Power Station, UK Cooling towers are evaporative coolers used for cooling water or other working medium to near the ambient wet-bulb air temperature. ... An electrically driven pump (electropump) for waterworks near the Hengsteysee, Germany. ... Look up condenser in Wiktionary, the free dictionary. ... York International water-cooled chiller. ...

Hot water system

The hot water system supplies heat to the building's air-handling units or VAV boxes. The hot water system will have a boiler(s) and pumps. Analog temperature sensors are placed in the hot water supply and return lines. Some type of mixing valve is usually used to control the heating water loop temperature. The boiler(s) and pumps are sequenced on and off to maintain supply. A boiler is a closed vessel in which water or other fluid is heated under pressure. ...

Alarms and security

Many building automation systems have alarm capabilities. If an alarm is detected, it can be programmed to notify someone. Notification can be through a computer, pager, cellular phone, or audible alarm. It has been suggested that Radio paging be merged into this article or section. ...

• Common temperature alarms are Space, Supply Air, Chilled Water Supply and Hot Water Supply.
• Differential pressure switches can be placed on the filter to determine if it is dirty.
• Status alarms are common. If a mechanical device like a pump is requested to start, and the status input indicates it is off. This can indicate a mechanical failure.
• Some valve actuators have end switches to indicate if the valve has opened or not.
• Carbon monoxide and carbon dioxide sensors can be used to alarm if levels are too high.
• Refrigerant sensors can be used to indicate a possible refrigerant leak.
• Amperage sensors can be used to detect low amperage conditions caused by slipping fan belts, or clogging strainers at pumps.

At sites with several buildings, momentary power failures can cause hundreds or thousands of alarms from equipment that has shutdown. Some sites are programmed so that critical alarms are automatically re-sent at varying intervals. For example, a repeating critical alarm (of a uninterruptible power supply in 'by pass') might resound at 10 minutes, 30 minutes, and every 2 to 4 hours there after until the alarms are resolved. Carbon monoxide, with the chemical formula CO, is a colorless, odorless, and tasteless gas. ... Carbon dioxide is a chemical compound composed of one carbon and two oxygen atoms, and is in a gaseous state in the atmosphere of the Earth. ... A refrigerant is a compound used in a heat cycle that undergoes a phase change from a gas to a liquid and back. ... An uninterruptible power supply (UPS), uninterruptible power source or sometimes called a battery backup is a device which maintains a continuous supply of electric power to connected equipment by supplying power from a separate source when utility power is not available. ...

Security systems can be interlocked to a building automation system. If occupancy sensors are present, they can also be used as burglar alarms.

Fire and smoke alarm systems can be hard-wired to override building automation. For example: if the smoke alarm is activated, all the outside air dampers close to prevent air coming into the building, and an exhaust system can isolate the alarmed area and activate an exhaust fan to move smoke out of the area. Life safety applications are normally hard-wired to a mechanical device to override building automation control. Fire alarm control panel (top) and graphic annunciator (bottom) for Potomac Hall, at James Madison University. ...

Room Automation

Room automation is the consolidation of one or more manual system in a room under centralized control. It has less do to with HVAC and more to do with presentation systems within a room. HVAC systems use ventilation air ducts installed throughout a building that supply conditioned air to a room through rectangular or round outlet vents, called diffusers; and ducts that remove air from return-air grills Fire-resistance rated mechanical shaft with HVAC sheet metal ducting and copper piping, as well as...

The most common example of room automation is corporate boardroom, presentation suites, and lecture halls, where the operation of the large number of devices that define the room function (such as Videoconferencing equipment, Video projectors, lighting control systems, Public address systems etc.) would make manual operation of the room very complex. It is common for room automation systems to employ a touchscreen as the primary way of controlling each operation. It has been suggested that H.331 be merged into this article or section. ... Projected image from a video projector in a home cinema. ... This article or section does not cite any references or sources. ... A public address system, abbreviated PA system, is an electronic amplification system used as a communication system in public areas. ... It has been suggested that Touch panel be merged into this article or section. ...

Manufacturers

• AMX LLC
• Crestron Electronics
• Dynalite

AMX LLC, commonly known as AMX, is a manufacturer of audio/visual control devices. ... Crestron Electronics is a company that makes high-end home automation systems. ... Dynalite, is an Australian control company that designs and manufactures technology solutions for lighting control, building automation, Home automation and room automation applications and sells its products worldwide. ...

Topology

Most building automation networks consist of a primary and secondary bus which contain programmable logic controllers, input/outputs and a user interface (also known as a human interface device). A Go North East bus parked in a lay-by in Tyne and Wear, England. ... PLC & input/output arrangements A Programmable Logic Controller, PLC, or Programmable Controller is a digital computer used for automation of industrial processes, such as control of machinery on factory assembly lines. ... Energy Input: The energy placed into a reaction. ... The user interface is the part of a system exposed to users. ...

The primary and secondary bus can be optical fiber, ethernet, ARCNET, RS-232, RS-485 or a wireless network. Optical fibers An optical fiber (or fibre) is a glass or plastic fiber designed to guide light along its length by confining as much light as possible in a propagating form. ... Ethernet is a large, diverse family of frame-based computer networking technologies that operates at many speeds for local area networks (LANs). ... ARCNET (also CamelCased as ARCnet, an acronym from Attached Resource Computer NETwork) is a local area network (LAN) protocol, similar in purpose to Ethernet or Token Ring. ... RS-232 (also referred to as EIA RS-232C or V.24) is a standard for serial binary data interchange between a DTE (Data terminal equipment) and a DCE (Data communication equipment). ... RS485 can be used to communicate with remote devices at distances up to 4000ft (1200m) at speeds of up to 100Kbps at this distance. ... While the term wireless network may technically be used to refer to any type of network that is wireless, the term is most commonly used to refer to a telecommunications network whose interconnections between nodes is implemented without the use of wires, such as a computer network (which is a...

Most controllers are proprietary. Each company has its own controllers for specific applications. Some are designed with limited controls: for example, a simple Packaged Roof Top Unit. Others are designed to be flexible. Most have proprietary software that will work with BACnet, LonTalk and ASHRAE standards. Proprietary indicates that a party, or proprietor, exercises private ownership, control or use over an item of property, usually to the exclusion of other parties. ... BACnet is a Data Communications Protocol for Building Automation and Control Networks. ... LonTalk is a protocol optimized for control created by Echelon Corporation for networking devices over media such as twisted pair, powerlines, fiber optics, and RF. It is popular for the automation of various functions in industrial control, home automation, transportation, and buildings systems such as lighting and HVAC; see Intelligent... The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) is an international voluntary organization for people involved in heating, ventilation, air conditioning, or refrigeration (HVAC&R). ... Standardization, in the context related to technologies and industries, is the process of establishing a technical standard among competing entities in a market, where this will bring benefits without hurting competition. ...

Inputs and outputs are either analog or digital (some companies say binary). It has been suggested that this article or section be merged with Analog electronics. ... A digital system is one that uses discrete values (often electrical voltages), especially those representable as binary numbers, or non-numeric symbols such as letters or icons, for input, processing, transmission, storage, or display, rather than a continuous spectrum of values (ie, as in an analog system). ... A Hexdump of a JPEG image. ...

Analog inputs are used to read a variable measurement. Examples are temperature, humidity and pressure sensor which could be thermistor, 4-20 mA, 0-10 Volt or Platinum RTD (resistance temperature detector), or wireless sensors. In computer science and mathematics, a variable (IPA pronunciation: ) (sometimes called a pronumeral) is a symbolic representation denoting a quantity or expression. ... This article includes a list of works cited or a list of external links, but its sources remain unclear because it lacks in-text citations. ... This article or section is not written in the formal tone expected of an encyclopedia article. ... The use of water pressure - the Captain Cook Memorial Jet in Lake Burley Griffin in Canberra, Australia. ... Distinguish from censure and censer and censor. ... NTC thermistor, bead type, insulated wires Thermistor symbol A thermistor is a type of resistor used to measure temperature changes, relying on the change in its resistance with changing temperature. ... 4-20 ma is an analog electrical transmission standard for industrial instrumentation. ... Josephson junction array chip developed by NIST as a standard volt. ... Look up RTD in Wiktionary, the free dictionary. ...

A digital input indicates if a device is turned on or not. Some examples of a digital input would be a 24VDC relay or air flow switch. Automotive style miniature relay A relay is an electrical switch that opens and closes under the control of another electrical circuit. ... Electrical switches. ...

Analog outputs control the speed or position of a device, such as a variable frequency drive, a I-P (current to pneumatics) transducer, or an actuator. An example is a hot water valve opening up 25% to maintain a setpoint. Small Variable Frequency Drive (VFD) A Variable Frequency Drive (sometimes abbreviated VFD) is system for controlling the rotational speed of an alternating current (AC) electric motor by controlling the frequency of the electrical power supplied to the motor. ... In electricity, current refers to electric current, which is the flow of electric charge. ... Table of Pneumaticks, 1728 Cyclopaedia This article is about the tool. ... A transducer is a device, usually electrical or electronic, that converts one type of energy to another. ... A three-dimensional actuator modelled using elastica theory. ... Setpoint is the target value that an automatic control system, for example PID controller, will aim to reach. ...

Digital outputs are used to open and close relays and switches. An example would be to turn on the parking lot lights when a photocell indicates it is dark outside. A photoresistor is an electronic component whose resistance decreases with increasing incident light intensity. ...

Protocols and Industry Standards

• ASHRAE (American Society of Heating, Refrigerating and Air Conditioning Engineers) is an international organization for people involved in heating, ventilation, air conditioning, or refrigeration (HVAC&R).
• BACnet is a network communications protocol for building automation and control systems.
• C-Bus
• DALI
• DSI
• Dynet
• Energy Star is program created by the United States government to promote energy efficient consumer products.
• KNX, a system for Home and Building Controls (promoted by "Konnex Association").
• LonTalk is a protocol created by Echelon Corporation for networking devices.
• Modbus
• oBIX
• ZigBee is a short range, low-powered wireless communication standard targeted at Building Automation.

The American Society of Heating, Refrigerating and Air Conditioning Engineers (ASHRAE) is an international voluntary organization for people involved in heating, ventilation, air conditioning, or refrigeration (HVAC&R). ... BACnet is a Data Communications Protocol for Building Automation and Control Networks. ... C-Bus is a home and building automation protocol that is used primarily in Australia, although it is also currently used throughout Asia, Russia, USA, South Africa and the UK. It is used in the control of domotics, or home automation systems, as well as commercial building lighting control systems. ... The Digitally Adressable Lighting Interface (DALI) is a digital protocol for the controlling of lighting in buildings (e. ... DSI is a protocol for dimming lighting (initially ballasts) it was created in 1991 by Austrian company Tridonic ATCO and is based on Manchester-coded 8 bit protocol, data rate of 1200 baud : 1 start bit, 8 data bits (dimming value), 4 stop bits and is the basis of the... Dynalite, is an Australian control company that designs and manufactures technology solutions for lighting control, building automation, Home automation and room automation applications and sells its products worldwide. ... The ENERGY STAR logo is placed on energy-efficient products ENERGY STAR is a United States government program to promote energy efficient consumer products. ... In physics and engineering, including mechanical and electrical engineering, energy efficiency is a dimensionless number, with a value between 0 and 1 or with times 100 given in percent. ... KNX is a standardised (EN 50090,ISO/IEC 14543), OSI-based network communications protocol for intelligent buildings. ... LonWorks is a networking platform specifically created to address the unique performance, reliability, installation, and maintenance needs of control applications. ... Echelon Corporation (NASDAQ: ELON) designs control networks to connect machines and other electronic devices, for the purposes of sensing, monitoring and control. ... Modbus is a serial communications protocol published by Modicon in 1979 for use with its programmable logic controllers (PLCs). ... // oBIX (for Open Building Information Exchange) is a standard for Web Services-based interfaces to building control systems. ... The introduction to this article provides insufficient context for those unfamiliar with the subject matter. ...

See also

• Building Management System
• Control engineering
• Control system
• Home automation
• Intelligent building
• HVAC control system
• Lighting control system
• Smart environment

Building Management System (BMS) is a computer software program, usually configured in a hierarchical manner, to control, monitor and manage all the equipment installed in the building. ... Control engineering is the engineering discipline that focuses on the mathematical modelling systems of a diverse nature, analysing their dynamic behaviour, and using control theory to make a controller that will cause the systems to behave in a desired manner. ... It has been suggested that this article or section be merged with Control theory. ... Light control computerized system Home automation (also called domotics) is a field within building automation, specializing in the specific automation requirements of private homes and in the application of automation techniques for the comfort and security of its residents. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... A HVAC control system is a computerized system for climate control in buildings. ... This article or section does not cite any references or sources. ... Smart environments is a technological concept that, according to Mark Weiser is a physical world that is richly and invisibly interwoven with sensors, actuators, displays, and computational elements, embedded seamlessly in the everyday objects of our lives, and connected through a continuous network [1] // Smart environments are envisioned as the...

External links

• eu.bac - European building automation and controls association
• CABA - Continental Automated Buildings Association