Watt Stopper UW-100 Ultrasonic Wall Switch Sensor

Ultrasonic Technology Switches Lights ON Even When Occupants Are Not in Clear Line of Sight


What's special about this ultrasonic switch?

  • Lights are switched on or off depending on the occupancy of the room, which means no more wasted money from lights left on all day.
  • Able to sense ambient lighting, that therefore your lights will not switch on SIMPLY because you entered the room, rather because you entered and need the lighting.
  • Utilizes high frequency ultrasound and Doppler Principle to detect occupancy and adjust lighting.
  • Highly sensitive to any movement in the area, whether large or small.
  • Attractive design is aesthetically appealing
  • Click for More Features

Part # Description Colors Weight Price
WS-UW-100 Ultrasonic Low Voltage Wall Switch Sensor Ivory, Almond, Wite, Light Almond, Black 0.4 lbs
Manufacturer Direct
  • Single junction box size fits easily into existing light switch boxes.
  • Lights switch off automatically once there is no one in the room and the time delay has elapsed.
  • Equipped with DIP switch settings which let you control your light settings: Auto-ON or Manual-ON operation, walkthrough and test modes.
  • Proprietary features eliminate the possibility of false triggers, and provide immunity to RFI and EMI.
  • Selectable SmartSet setting automatically adjusts delay for maximum savings and efficiency.
  • Opt to activate or deactivate the audible and/or visual alerts prior to lights powering down.
  • Override mode will allow you to operate your switch manually in the unlikely event that there is a system failure.
  • 5-year manufacturer’s warranty


    SmartSet technology is what allows the UW-100 to constantly monitor the room to detect patterns of usage, and automatically adjust the time delay for maximum energy efficiency. Your switch will assign short shut off time delays (as little as seven minutes) for times when the room is usually empty, and longer delays (up to 30 minutes) when there is more traffic. Incredibly accurate and intuitive device can sense the difference between electrical noise and human motion for greater performance.

    Your sensor switch will work with fluorescent and incandescent lighting loads, and is compatible with energy-efficient electronic ballasts. Since the sensors use ultrasonic sound waves to detect motion, there is no need to have a clear line of sight.



  • Perfect for use in areas where the sensor may have a partially obstructed line of sight from the people who may enter the room.
  • Excellent for restrooms, restrooms with two stalls and utility/storage rooms.
  • DO NOT use ultrasonic wall switch sensors:
  • In areas where the doors will remain open
  • In areas with excessive air flow
  • For emergency or exit lighting
  • Within six feet of an air duct

  • UW-100 Specifications - (PDF) PDF
  • Technical Bulletin - (PDF) PDF

    Voltages 120/ 230/ 277VAC, 50/60Hz
    Sensor Type: Ultrasonic
    Load Limit for Relay: 120/230/277 VAC; 50/60 Hz
    @ 120 VAC, 0-800 W ballast or tungsten,1/6 hp
    @ 230/277 VAC, 0-1200 W ballast
    Coverage (Square Feet): 400
    Load Type Compatibility: Incandescent, fluorescent, magnetic or electronic ballast
    Installation Type: Wall
    Horsepower Rating (each relay): 1/6 HP @120VAC
    Time Delay Adjustment: SmartSet (automatic), fixed (5, 10, 15, 20, 25 or 30 minutes), walk-through, testmode
    Walk Through Mode: 3 minutes if no activity after 30 seconds
    Viewing Angle (Degrees): 180
    Test Mode: 5 seconds at initial power up or DIP switch reset
    Time Delay: Adaptive/ Manual
    Ultrasonic Mode: Minimum to Maximum (trimpot), Off
    Frequency: 40kHz
    Light Level Adjustment: 8 fc to 180+fc
    Alerts: Selectable Audio and Visible
    Weight: 0.4 lb
    US Patents: 5640113 and 6617560B2


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