Product Details

The SL-350QN includes even more features to protect against false and missed alarms caused by mis-alignment and environmental issues. With 350ft. of outdoor detection range, the QN model is perfect for mid level security perimeter applications. New features include:

Quad beam - Dramatically cuts down on false alarms caused by birds and falling leaves

Sniper ViewFinder and alignment dial - The new telescope lens on the SL Series has a high level of visibility for optical alignment work. Even at 350ft., a perfect installation and stable performance can be achieved in minimal time.

BAU-4 Compatible - The BAU-4 beam alignment unit automatically and accurately adjusts the optical access. This allows peak performance and gives one technician the ability to align a 200ft to 650ft SL detector without additional help.

  • 350ft. outdoor detection range
  • IP65 rated
  • Alignment dial
  • Sniper viewfinder with x2 magnification
  • Vivid interior color
  • Quad beam detection pattern

OPTEX National Defense Authorization Act Declaration


  • Perimeter
  • Roof / Ceiling
  • Garden
  • Driveway

Key Features

  • 350ft. Outdoor Quad Photoelectric Detector with Sniper Viewfinder
  • IP65 rated
  • Alignment dial



The key success of a reliable active infrared intrusion system relies on the accuracy of the beam or beam tower alignment. If the transmitting ‘beams’ and the receiving ‘beams’ are not well aligned, there is a risk of severe environmental interference from fog and sunlight, even more so if the beams are 350 feet or 650 feet apart.

When installing beam towers around a perimeter there is the tendency to think that the towers should be at a 90 degree angle from each other. Actually, a 90 degree angle can restrict the view for the signal due to the tower extrusion lip. Our technical team recommends mounting the beam towers at a 45 degree angle on the ground, this allows the beam mounted inside the tower a clear view and gives the installer some flexibility for alignment.

If you are using a floor mount enclosure, the same principle applies: you should dig a 45 degree angled square in the ground to install the ground bracket. For a more efficient method, our tech team highly recommends using theTW SSL (Included in our beam enclosure) an adjustable mounting plate specifically designed for our Smart Line Beam series. The Smart Line beam can be fixed on to the TW SSL then the plate can be clipped in to the beam tower. Using this method, alignment can be easily facilitated by simply adjusting the plate up or down in the grooves to set it at the right height.

OPTEX also recommends using a voltmeter during the beam alignment process. Please refer to the owner's manual for the proper voltage needed for beam alignment.

The beams can operate between 10.5vDC to 30vDC. When connecting to an intruder system, 12vDC will be sufficient. If however, you’re using a heater unit (HU-3) you will need a 24vDC supply. Our wireless beams will need 2 or 4 3.6v lithium batteries.

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