Hierarchy classification:

1. top of the aat hierarchies
2. Objects Facet
3. Object Groupings and Systems (hierarchy name)

Narrower term/s

• system components [NP][+]
  • electrical system components [+]
    • actuators
    • oscillators
    • transistors
    • electron tubes [+]
      • diodes [+]
      • vacuum tubes [+]
    • capacitors
    • electrodes [+]
      • ion-selective electrodes
    • insulators
    • resistors
    • rheostats [+]
      • potentiometers [NP]
    • rheotomes
    • raceways [+]
      • busways
    • electric cables [+]
      • armored cables
      • power cables
    • circuit breakers
    • circuits
    • electric conduits
    • switchboards
    • electric switches
    • electric wiring
    • ground-fault circuit interruptors
    • power outlets
    • panelboards
    • receptacles
    • transformers [+]
      • step-down transformers
      • step-up transformers
    • circuit boards
    • occupancy sensors
    • photovoltaic cells [+]
      • solar cells
    • punch blocks (electrical connections)
    • magnetrons
    • [temporary alphabetical list: electrical system components] [+]
      • alligator clips
      • anodes
      • ballast tubes
      • battery adapters
      • battery charger adapters
      • battery jars
      • battery testers
      • cable fault locators
      • AC-DC converters
      • binding posts
      • cathodes
      • decade boxes
      • dimmer switches
      • electric wires
      • electrical adapters
      • electrical boxes
      • electrical chokes
      • [electrical maintenance & repair equipment]
      • electrical modulators
      • electrical outlets
      • electrical plugs
      • electrical shunts
      • electrical switches
      • electrical terminals
      • electrical testers
      • electrical tubes
      • electrician's pliers
      • electrolytic capacitors
      • extension cords
      • fuse blocks
      • fuse boxes
      • fuse pullers
      • impedance transformers
      • induction coils
      • growlers
      • junction boxes
      • knife switches
      • magneto and coil testers
      • outlet boxes
      • relays
      • resistance boxes
      • resonant transformers
      • plug adapters
      • power cords
      • receptacle plugs
      • transfer switches
      • tube sockets
      • utility boxes
      • variable capacitors
      • voltage multipliers
      • single side band modulators
      • socket covers
      • socket plugs
      • wire nuts
      • wire sorters
      • solenoids
      • solenoid switches
      • spark arresters
      • tesla coils
      • time switches
  • [plumbing and stormwater system components] [+]
    • leader heads
    • catch basins
    • cesspools
    • cisterns (plumbing components)
    • drains [+]
      • area drains
      • fixture drains
      • storm drains
      • French drains
    • gutters (building drainage components) [+]
      • arris gutters
      • valley gutters
      • back gutters
      • eaves gutters
    • piping (plumbing system components) [+]
      • downspouts
      • drainage piping
      • DWV piping
      • mains (plumbing)
      • stacks (piping) [+]
      • risers (piping)
      • service pipes
      • pipe fittings (components)
    • plumbing fixtures [+]
      • drinking fountains
      • washfountains
      • bathtubs [+]
      • bidets (plumbing fixtures)
      • sinks (fixtures) [+]
      • toilets (fixtures) [+]
      • urinals (plumbing fixtures)
      • laundry trays
      • water conditioners
      • shower heads
      • bath basins
    • seepage pits
    • septic tanks
    • sumps
    • traps (plumbing system components) [+]
      • fixture traps
      • house traps
    • water heaters [+]
      • solar water heaters
    • water storage tanks
    • leaching fields
    • impluvia
    • waterspouts [+]
      • gargoyles
      • lion-head spouts
      • śuṇḍu
    • safes (plumbing components)
    • rain barrels
    • [temporary alphabetical list: plumbing and stormwater system components] [+]
      • bathroom sinks
      • drain covers
      • indoor fountains
      • kitchen sinks
      • pedestal sinks
      • plumbing & drainage elements
      • plumbing pipes
      • plumbing pumps
      • sink sprayers
      • sink stoppers
      • water heater stands
      • water supply pipes
    • nāla
  • HVAC components [+]
    • ventilation system components [+]
      • ventilators (ventilation components)
      • air filters [+]
      • air-handling units
      • blowers
      • dampers (HVAC components)
      • air distribution systems
      • air diffusers
      • air ducts
      • registers (HVAC components)
      • cowls (ventilation system components)
      • plenum chambers
      • fume hoods
    • [cooling, heating and humidifying components] [+]
      • furnaces (heating components) [+]
      • air washers
      • boilers (HVAC components) [+]
      • cooling towers
      • heat pumps [+]
      • heat exchangers [+]
      • thermostats
      • radiator enclosures
      • breechings
      • trompes (cooling components)
      • solar thermal panels
      • stovepipes (pipes)
    • heat-distributing units [+]
      • baseboard units
      • convectors
      • radiators
      • thermal masses
  • telecommunication systems components [+]
    • television receivers
    • radio receivers
    • telephones [+]
      • cellular telephones
      • smartphones
    • transceivers [+]
      • walkie-talkies
    • antennas [+]
      • [antennas by form] [+]
      • [antennas by function] [+]
    • field telephones
    • telephone wires
    • microphones [NP] [+]
      • dynamic microphones
      • ribbon microphones
      • condenser microphones
      • lavaliers
    • telegraphs [+]
      • engine-room telegraphs
    • liquid crystal displays
    • remote controls
    • [temporary alphabetical list: telecommunication systems components] [+]
      • answering machines
      • antenna insulators
      • antenna lead cables
      • antenna rotors
      • antenna wires
      • cable connectors
      • cable converters
      • communication insulators
      • console radios
      • console televisions
      • cordless telephones
      • car radios
      • cb radios
      • coaxial cables
      • coherers
      • coin-operated telephones
      • color converters
      • crystal radios
      • descramblers
      • desk telephones
      • instructographs
      • grounding rods
      • headsets
      • magneto telephones
      • pagers
      • morse code instruction devices
      • natrometers
      • omnigraphs
      • remote servos
      • rooftop antennas
      • portable radios
      • portable televisions
      • radio antennas
      • radio frequency amplifiers
      • radio headsets
      • radio scanners
      • radio transmitters
      • radio tuners
      • radiophones
      • transistor radios
      • transmitters (telecommunication )
      • transponders
      • satellite dishes
      • satellite telephones
      • scramblers
      • set-top antennas
      • uhf converters
      • varioplexes
      • signal splitters
      • wall telephones
      • stock tickers
      • submarine cables
      • table radios
      • tdds
      • telecommunication accessories
      • telecommunication cables
      • telecommunication devices
      • telecommunication equipment cases
      • telecommunication media
      • telecommunication wire
      • telegraph keys
      • telegraph printers
      • telegraph sounders
      • telegraph wires
      • telegraph wire insulators
      • telemeters
      • telephone cables
      • telephone cases
      • telephone jacks
      • telephone line doublers
      • telephone switchboards
      • telephone wire insulators
      • teleprinters
      • teletypes
      • teletypewriters
      • television antennas
      • television converters
      • television transmitters
      • television tuners
      • ticker tape
      • ticker tape machines
    • fax machines
    • televisions (viewing devices)
  • infrastructural elements [+]
    • dam elements [+]
      • fishways
      • spillways
      • stilling basins
      • penstocks
    • transportation elements [+]
      • bridge elements [+]
      • [road and roadside elements] [+]
      • grade crossings
      • transit system elements [+]
      • roadbeds
    • utilities components [+]
      • water mains
      • utility poles [+]
      • power lines
      • gas pipelines
      • oil pipelines [+]
      • oil pumping stations
  • protection system components [+]
    • fire alarm system components [+]
      • fire detectors [+]
      • smoke detectors [+]
      • manual stations
    • fire extinguishing system components [+]
      • fire sprinklers
    • security system components [+]
      • burglar alarms
    • [temporary alphabetical list: protection system components] [+]
      • alarms
      • gas alarms
      • gas detectors
      • gas mask carriers
      • fire alarm boxes
      • fire protection devices [+]
      • protective devices
      • security card readers
      • security devices
      • security keypads
      • security locks
      • security scanners
      • smoke alarms
      • x-ray security scanners
      • sandbags
• [systems by function][+]
  • waterworks
  • electrical systems [+]
    • emergency power supply
    • grounded systems
    • electrical system components [NP] [+]
      • actuators
      • oscillators
      • transistors
      • electron tubes [+]
      • capacitors
      • electrodes [+]
      • insulators
      • resistors
      • rheostats [+]
      • rheotomes
      • raceways [+]
      • electric cables [+]
      • circuit breakers
      • circuits
      • electric conduits
      • switchboards
      • electric switches
      • electric wiring
      • ground-fault circuit interruptors
      • power outlets
      • panelboards
      • receptacles
      • transformers [+]
      • circuit boards
      • occupancy sensors
      • photovoltaic cells [+]
      • punch blocks (electrical connections)
      • magnetrons
      • [temporary alphabetical list: electrical system components] [+]
  • conveying systems [+]
    • vertical conveying systems [+]
      • dumbwaiters (conveying systems)
      • elevators [+]
      • manlifts
      • platform lifts
    • [diagonal and multidirectional conveying systems] [+]
      • inclined elevators
      • escalators
      • inclined lifts [+]
      • moving ramps
      • pneumatic tubes
    • horizontal conveying systems [+]
      • moving walkways
  • HVAC [+]
    • heating systems [+]
      • furnaces (heating components) [NP] [+]
      • resistance heating
      • hot water heating
      • radiant heating [+]
      • solar heating (systems) [+]
      • steam heating [+]
      • warm air heating [+]
      • heat-distributing units [NP] [+]
    • ventilation (systems) [+]
      • exhaust ventilation (systems)
      • mechanical ventilation (systems)
      • natural ventilation (systems)
      • ventilation system components [NP] [+]
    • air conditioning [+]
      • central air conditioning
      • incremental air conditioning
      • air washers [NP]
    • air cooling [+]
      • chilled water systems
      • refrigerant systems
      • ice storage systems
      • passive cooling
    • HVAC components [NP] [+]
      • ventilation system components [+]
      • [cooling, heating and humidifying components] [+]
      • heat-distributing units [+]
    • [temporary alphabetical list: HVAC] [+]
      • chiller systems
      • coal furnaces
      • dehumidifiers
      • environmental control elements
      • exhaust fans
      • fireboards
      • fireplace dampers
      • fireplace doors
      • hvac boilers
      • hvac coils
      • hvac compressors
      • hvac condensers
      • hvac evaporators
      • hvac filters
      • recirculating fans
      • vent caps
      • ventilation fans
      • ventilator damper
  • lighting [+]
    • [lighting by method of illumination] [+]
      • electric lighting
      • gas-lighting
      • fluorescent lighting
      • daylighting
      • artificial lighting
    • [lighting by location or context] [+]
      • exterior lighting
      • interior lighting [+]
      • stage lighting
    • [lighting by function] [+]
      • architectural lighting [+]
      • emergency lighting
  • stormwater systems
  • communication systems (mechanical and electrical systems) [+]
    • television antenna systems
    • clock and program systems
    • sound systems [+]
      • intercom systems
      • public address systems
      • doorbells [+]
      • sound-reproducing systems
      • audioguides
      • call bells
    • NTSC system
  • protection systems [+]
    • fire protection systems [+]
      • fire alarm systems [+]
      • fire extinguishing systems [+]
    • security systems [+]
      • electronic security systems
      • security system components [NP] [+]
    • protection system components [NP] [+]
      • fire alarm system components [+]
      • fire extinguishing system components [+]
      • security system components [+]
      • [temporary alphabetical list: protection system components] [+]
  • plumbing systems [+]
    • [plumbing and stormwater system components] [NP] [+]
      • leader heads
      • catch basins
      • cesspools
      • cisterns (plumbing components)
      • drains [+]
      • gutters (building drainage components) [+]
      • piping (plumbing system components) [+]
      • plumbing fixtures [+]
      • seepage pits
      • septic tanks
      • sumps
      • traps (plumbing system components) [+]
      • water heaters [+]
      • water storage tanks
      • leaching fields
      • impluvia
      • waterspouts [+]
      • safes (plumbing components)
      • rain barrels
      • [temporary alphabetical list: plumbing and stormwater system components] [+]
      • nāla
    • water distribution systems [+]
      • downfeed systems
      • upfeed systems
    • sanitary drainage systems
  • infrastructural systems [+]
    • transit systems (infrastructure) [+]
      • railroads (infrastructure)
      • public transit (infrastructure) [+]
    • utilities (infrastructures) [+]
      • water supply systems [+]
      • municipal lighting
      • street lighting
      • utilities components [NP] [+]
    • telecommunication systems [+]
      • police communication systems
      • telephone systems [+]
      • telecommunication systems components [NP] [+]
      • television (telecommunication system) [+]
      • radio (telecommunication system) [+]
      • intranets
      • wireless sensor networks
      • telex
    • drainage systems
    • Internet [+]
      • World Wide Web [+]
  • signage
  • seating [+]
    • icpalli (seat)
  • geographic systems [+]
    • geographic information systems
    • Global Positioning System
    • Electron Marker System
  • film projection systems [+]
    • VistaVision (TM)
  • computer systems [+]
    • information systems [+]
      • cataloging systems
      • collection management systems
  • digital projection
• [systems by location or context][+]
  • building systems [+]
    • mechanical systems
  • home entertainment systems [+]
    • home theaters

Anotations

Scope note:

Designates complex assemblies of equipment and activities, arranged according to some scheme or plan, and intended to perform specific functions.