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Photo Eye / Entrapment Device Setup

Installing and aligning photo eyes and entrapment protection devices per UL 325. Covers layout planning and bracket mounting, sensor installation, low-voltage wiring and operator connection, beam alignment, reversal and obstruction testing, monitored sensing edges and constant-pressure mode for commercial applications, and final documentation and labeling of the safety devices.

BasicInstallation30–60 min1 person

Warnings

This procedure should only be performed by qualified technicians familiar with the operator and applicable UL 325 safety requirements.

Per UL 325, all operator-equipped doors must have functioning entrapment protection devices. A door without working safety devices must not be left in service.

Photo eyes must be mounted no higher than 6 inches above the floor to detect small objects and children.

Do not route low-voltage sensor wiring in the same conduit as line-voltage (120V/240V) wiring. Electromagnetic interference can cause false signals and safety device malfunction.

Required PPE

  • Safety glasses
  • Steel-toed boots

Tools Required

  • Photo eye sensor kit (sending and receiving units with mounting brackets)
  • Monitored sensing edge (if applicable)
  • Low-voltage wire (typically 22 AWG bell wire, 2-conductor)
  • Wire strippers and wire nuts
  • Power drill with bit set
  • Screwdrivers (flat and Phillips)
  • Tape measure
  • Level
  • Cable staples or wire clips
  • Multimeter
  • Small Phillips screwdriver (for alignment adjustment)
  • Obstruction test object (2x4 lumber)

Procedure — 6 Steps

Step 1 of 60% complete

Step 1

Plan Sensor Layout and Mount Brackets

Photo eyes must be mounted no higher than 6 inches above the floor to detect small objects and children. Mounting the beam too high defeats the entrapment protection required by UL 325.

Plan the sensor layout before drilling. Determine the mounting locations for the sending and receiving photo eye units — one on each side of the door opening. The sensors must be mounted no more than 6 inches above the floor, with the infrared beam crossing the full width of the opening. Plan the wire routing path from each sensor to the operator unit, keeping low-voltage wiring separated from line-voltage wiring by at least 12 inches. Once the layout is set, mount the sensor brackets: install the mounting brackets on the door frame, wall, or track angle at the planned locations using the hardware provided with the sensor kit. For masonry or steel jambs, pre-drill with the appropriate bit. Ensure both brackets are at the same height so the beam will be level, and use a tape measure to verify equal height from the floor on both sides.

Pro Tips

  • Use a level or a measured mark on each jamb to keep the two brackets at the identical height — a beam that is not level is harder to align and can cause intermittent detection.
  • Route the low-voltage sensor path away from any existing line-voltage runs; maintaining at least 12 inches of separation prevents electromagnetic interference from the start.
  • Track angle, wall, and door frame are all acceptable mounting surfaces — pick the location that keeps the beam unobstructed across the full opening width.
  • For masonry or steel jambs, select and pre-drill with the correct bit before fastening so the bracket sits flush and solid.
  • Confirm the beam path is clear of springs, brackets, and stored items before committing to the mounting spots.

Checklist

Training Videos

Disclaimer: These videos are produced by third-party YouTube channels and are not affiliated with Doorbot. Video content may not align exactly with the procedures above, may depict techniques that differ from DASMA or manufacturer recommendations, and may show tasks that are dangerous if performed without proper training and equipment. Always follow the written procedure, your company's safety policies, and applicable industry standards. Use these videos as supplementary reference only.

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References & Standards