Building Management System
Encyclopedia
A Building Management System (BMS) is a computer
Computer
A computer is a programmable machine designed to sequentially and automatically carry out a sequence of arithmetic or logical operations. The particular sequence of operations can be changed readily, allowing the computer to solve more than one kind of problem...

-based control system installed in buildings that controls and monitors the building’s mechanical and electrical equipment such as ventilation
Ventilation (architecture)
Ventilating is the process of "changing" or replacing air in any space to provide high indoor air quality...

, lighting
Lighting
Lighting or illumination is the deliberate application of light to achieve some practical or aesthetic effect. Lighting includes the use of both artificial light sources such as lamps and light fixtures, as well as natural illumination by capturing daylight...

, power systems, fire systems, and security systems. A BMS consists of software and hardware; the software program, usually configured in a hierarchical manner, can be proprietary, using such protocols as C-bus, Profibus
Profibus
PROFIBUS is a standard for field bus communication in automation technology and was first promoted in 1989 by BMBF...

, and so on. Vendors are also producing BMSs that integrate using Internet protocol
Internet Protocol
The Internet Protocol is the principal communications protocol used for relaying datagrams across an internetwork using the Internet Protocol Suite...

s and open standards such as DeviceNet
DeviceNet
DeviceNet is a network system used in the automation industry to interconnect control devices for data exchange. It uses Controller Area Network as the backbone technology and defines an application layer to cover a range of device profiles...

, SOAP
SOAP
SOAP, originally defined as Simple Object Access Protocol, is a protocol specification for exchanging structured information in the implementation of Web Services in computer networks...

, XML
XML
Extensible Markup Language is a set of rules for encoding documents in machine-readable form. It is defined in the XML 1.0 Specification produced by the W3C, and several other related specifications, all gratis open standards....

, BACnet
BACnet
BACnet is a communications protocol for building automation and control networks. It is an ASHRAE, ANSI, and ISO standard protocol....

, LonWorks
LonWorks
LonWorks is a networking platform specifically created to address the needs of control applications. The platform is built on a protocol created by Echelon Corporation for networking devices over media such as twisted pair, powerlines, fiber optics, and RF...

 and Modbus
Modbus
Modbus is a serial communications protocol published by Modicon in 1979 for use with its programmable logic controllers . Simple and robust, it has since become one of the de facto standard communications protocols in the industry, and it is now amongst the most commonly available means of...

.

Characteristics

A BMS is most common in a large building. Its core function is to manage the environment within the building and may control temperature, carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...

 levels and humidity within a building. As a core function in most BMS systems, it controls heating and cooling, manages the systems that distribute this air throughout the building (for example by operating fans or opening/closing dampers), and then locally controls the mixture of heating and cooling to achieve the desired room temperature. A secondary function sometimes is to monitor the level of human-generated CO2, mixing in outside air with waste air to increase the amount of oxygen
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...

 while also minimising heat/cooling losses.

Systems linked to a BMS typically represent 40% of a building's energy usage; if lighting is included, this number approaches 70%. BMS systems are a critical component to managing energy demand. Improperly configured BMS systems are believed to account for 20% of building energy usage, or approximately 8% of total energy usage in the United States.

As well as controlling the building's internal environment, BMS systems are sometimes linked to access control (turnstiles and access doors controlling who is allowed access and egress to the building) or other security systems such as closed-circuit television (CCTV) and motion detectors. Fire alarm systems and elevators are also sometimes linked to a BMS, for example, if a fire is detected then the system could shut off dampers in the ventilation system to stop smoke spreading and send all the elevators to the ground floor and park them to prevent people from using them in the event of a fire.

History

Building Management Systems have been employed for as long as commercial buildings have existed, whether this be through manpower loading coal into coal fired boilers or opening water pipe valves manually with the use of a handle so to enable heated water to flow through a radiator circuit. However, "BMS" as a phrase, is relatively new, the concept being introduced in the early 1970s (the terms BAS-building automation system, and EMS-energy management system are also used); the phrase has only really existed since the introduction of complex electronic devices that are capable of retaining data for the purposes of managing services such as power, lighting, heating and so on. It was the advent of the "modem", or "modulator-demodulator" which allowed analog signals to be digitized so that they could be communicated over long distances with a high degree of accuracy that spurred the development and deployment of modern BMSs. The Powers 570 was an example of such a system. Developed and marketed by Powers Regulator Company (later purchased by Siemens), it was deployed into the market in May 1970, as the model number suggests.

Before the modern, computer-controlled BMSs came into being, various electromechanical systems were in use to control buildings. Many facilities management offices had panels consisting of manual switches or more commonly, lights showing the status of various items of plant, allowing building maintenance staff to react if something failed. Some of these systems also include an audible alarm. Advancements in signal communications technology have allowed the migration of early pneumatic and "home run" hard wired systems, to modems communicating on a single twisted pair cable, to ultra fast IP based communication on "broad band" or "fiber optic" cable.

Functions of Building Management Systems

The three basic functions of a central, computer-controlled BAS are:
  • controlling
  • monitoring
  • optimizing


the building’s facilities, mechanical, and electrical equipment for comfort, safety, and efficiency.

A BMS normally comprises

  • Power systems
  • Illumination system
  • Electric power control system
  • Heating,Ventilation and Air-conditioning HVAC
    HVAC
    HVAC refers to technology of indoor or automotive environmental comfort. HVAC system design is a major subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer...

     System
  • Security and observation system
  • Magnetic card and access system
  • Fire alarm system
    Fire alarm system
    An automatic fire alarm system is designed to detect the unwanted presence of fire by monitoring environmental changes associated with combustion. In general, a fire alarm system is classified as either automatically actuated, manually actuated, or both...

  • Lifts
    Elevator
    An elevator is a type of vertical transport equipment that efficiently moves people or goods between floors of a building, vessel or other structures...

    , elevators
    Elevator
    An elevator is a type of vertical transport equipment that efficiently moves people or goods between floors of a building, vessel or other structures...

     etc.
  • Plumbing system
  • Burglar alarms
  • Trace Heating
  • Other engineering systems
  • Home Automation System

Building tenant/occupants

  • Good control of internal comfort conditions
  • Possibility of individual room control
  • Increased staff productivity
  • Effective monitoring and targeting of energy consumption
  • Improved plant reliability and life
  • Effective response to HVAC
    HVAC
    HVAC refers to technology of indoor or automotive environmental comfort. HVAC system design is a major subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics, and heat transfer...

    -related complaints
  • Save time and money during the maintenance
  • Control Of Buiding

Building owner

  • Higher rental value
  • Flexibility on change of building use
  • Individual tenant billing for services facilities manager
  • Central or remote control and monitoring of building
  • Increased level of comfort and time saving
  • Remote Monitoring of the plants (such as AHU's, Fire pumps, plumbing pumps, Electrical supply, STP, WTP etc.)

Maintenance Companies

  • Ease of information availability problem
  • Computerized maintenance scheduling
  • Effective use of maintenance staff
  • Early detection of problems
  • More satisfied occupants
The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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