Glossary of Terms

This page gives definitions of the various terms and acronyms used in this web site.

Access control  - system used to control the entrance and exit of people in buildings

AHU = Air Handling Unit  - equipment used to ventilate and condition air in buildings

Air Damper  - set of blades used to control the flow of air in ducts

Alarm  - a message that communicates a fault or emergency condition

AM&T = Automatic Monitoring and Targeting  - software which can analyse building condition and utility usage data

API = Application Program Interface

Archive log  - a historical record of data, typically temperature or energy usage

Auto-changeover  - term used to describe control logic used to manage usage of a pair of pumps or fans

Automatic control  - general term used for computerised control of building conditions

Back-up  - the process of automatically creating a copy of configuration and status data for use if the original data is lost or corrupted

BMS = Building Management System

Boiler  - a unit which generates hot water for heating and other purposes, generally gas or oil fuelled

CCTV = Closed Circuit Television  - term commonly used for video cameras used in surveillance applications

Ceiling cassette A/C unit  - type of air-conditioning unit which is ceiling mounted and uses refrigerant for cooling

Chiller  - unit which generates cold water (typically 4-8 degC) for cooling purposes in buildings

Component library - collection of software modules used to create control strategies

Condenser  - unit which extracts heat from a space using the refrigerant cycle

Control strategy  - a particular set of software modules connected in a specific way to determine the control regime in a building

Cooling battery/coil  - a piping arrangement to enable the cooling of air in a section of duct

CW – Chilled Water - cold wate, typically 4-8 degC generated by a chiller, used for cooling a building

Database  - a program designed to store multiple sets of data

DDC – Direct Digital Control

Differential pressure (DP) switch 

DIN rail mounting  - commonly used mounting arrangement for controllers and I/O modules in panels and other housings

Duct temperature sensor  - electronic device for measuring temperature in air ducts

DVR = Digital Video Recorder

DX Cooling  - direct cooling of air or water using refrigerant cycle rather than chilled water

Embedded - used to refer to a controller which uses solid state memory (no hard drive) and is designed for building into equipment or buildings

Energy Management  - general term for systems designed to manage energy usage

Evaporator  - unit which dissipates heat from a refrigerant cycle air-cnditioning system, typically using a fan and a coli

Fan  - unit which consists of electric motor and blades for creating air movement in ducting

Fan-coil controller  - small electronic controller designed to manage a zone A/C unit with fan and heating and/or cooling coils

Fieldbus  - term used for serial networks run around buildings, typically wired using twisted pair cable 

Filter  - unit which manages particulate content of air in ventilation ducting

Fire detection system  - consists of smoke and heat detectors and alarm devices to signal the occurence of a fire

FM - Facilities Management - general term for processes, tasks, services and technologies used to maintain buildings

Frost protection coil  - a piping arrangement in ducting to enable heating so as to prevent freezing conditions 

Gateway  - electronic device which converts data from one network protocol to another

GPRS = General Pack Radio Service  - technology that enables continuous data transmission using the mobile telephone networks

Graphical configuration  - a very visual process used to create control strategies on a computer using click & drag techniques to link s/w modulesHand/Off/Auto  - term used for the ability to manually override the status of a control output, typically using a three position switch

Heating battery/coil  - a piping arrangement to enable heating of air in ducts

Humidity sensor  - an electronic device for measuring relative humidity in occupied spaces or air ducts

HVAC = Heating Ventilation & Air-conditioning

HW = Hot water, typically generated by a boiler(s) for heating a building and providing hot water for domestic use

Intruder alarm system  - detectors and alarm device(s)to signal unauthorised access to a building

I/O module  - a small electronic module which has terminals for direct wired connection of inputs such as sensors and outputs such as actuators

IPv6loWPAN = IP version 6, low powered Wireless Personal Area Network

JACE = JAVA Appliaction Control Engine - name of embededd processor hardware platform to run Niagara AX

M2M = Machine to Machine  - term used for any application where multiple devices or systems are monitored/controlled remotely tyopically using GPRS comms

Mesh network  - a wireless network in which each device can transmit and receive enabling messages to be dynamically re-routed to avoid interference

Middleware  - term used for software which normalises data from disaparet sources and protocols

Network protocol  - a particular form of data encoding and communications management used to transmit data between multiple devices

NVM = Network Video management

Object model - term used to describe software building blocks which can be combined to achieve specific functionality

OEM = Original Equipment manufacturer

Open standard

Outside air temperature sensor

PID loop (Proportional, Intergal, Derivative)  - technique used to optimise analog control, typically of temperature, humidity or pressure

Pump  - unit consisting of an electric motor and blades that creates water flow around a piping system

Scaleable architecture  - ability of a network management solution to manage many thousands of controllers in many locations as a single system

Serial port  - a connection on a controller used for serial networks (fieldbuses), typically using RS232 or RS485 electrical standards

Smoke Damper  - a set of parallel blades used to stop smoke and heat transfer along a duct in the event of a fire

Software driver  - a module of computer coding which enables Niagara to communicate with a specific network protocol

Space Temperature sensor  - electronic device that measures temperature in internal rooms and areas of a building

Split A/C unit  - type of air-conditioning unit which consists of an evaporator and condenser linked by refrigerant piping

Utility Billing  - term used for the process of invoicing for energy and water usage

Valve  - a device used to control water or refrigerant flow in piping

VAV controller (Variable Air Volume) - small controller used to manage a zone A/C unit which uses pressure control of air dampers

Water leak detection system  - used to monitor sub-floor areas where there is a high risk of flooding or serious consequences if a leak occurs

Web page  - graphics and text transmitted via an IP network for display in a browser 

Wi-Fi  - common term for an 802.11 wireless IP network

Wireless  - general term used to describe technologies which enable transmission of data without use of wires, commonly radio but also powerline

Wiring schedule  - document which details the exact way in which each terminal on a controller is to be wired in the panel