Wallace Perimeter Security ALPHA, Installation And Maintenance Manual, Page: 147 / 182

Alpha/Delta (Kinetic Operator) Installation and Maintenance Manual Revision 1 - MAY 2023
147
PHOTO EYE MOUNTING AND ALIGNMENT
Photo Eye Mounting and Alignment
Alignment:
Most photo eyes require careful optical alignment in order to aim the emitter beam to the center of
the receiver or reflector. In order to avoid false triggering, it is important to carefully align the system,
especially with retro reflective photo eyes. The best way to assure true centering of the beam is with some
trial testing where the emitter is shifted to move the beam left and right and up and down until the range
of the invisible cone of the infrared beam is known. Photo eyes usually provide alignment aid LED’s for
this setup, but they can be hard to see. HySecurity has provided a unique feature that turns power on to
the photo eyes and causes the buzzer to chirp when the photo eyes enter and exit alignment. See
“Table
5. SmartDC Controller - User Menu Functions” on page 94 to enable this feature. Set the menu item
PE - PHOTO EYE ALIGN from a 0 to a 1. The buzzer chirps once when the emitter and photo eye receiver
are not aligned. When the emitter and receiver are aligned, the buzzer chirps twice. If they go out of
alignment again, the buzzer will chirp once. This “alignment mode” will automatically reset to 0 the next
time the Close Limit Switch is triggered or the RESET key is pressed.
Notes about retro-reflective systems:
Correct installation and alignment of a retro-reflective photo eye and its reflector is important for trouble-
free performance. Any system operating at a range greater than 16 feet (4.88m) is more prone to false
triggering due to dirty optics, condensation, or poor weather. If care is taken in the initial mounting and
alignment of the 3-inch (7.62cm) reflector, the chance of problems is greatly reduced. Use only through-
beam photo eyes for a distance greater than 24 feet (7.32m) because the function of a retro-reflective
photo eye will be too unreliable.
Taking steps to protect the photo eye and the reflector from being exposed to fog and being absolutely
certain the photo eye is perfectly aligned will greatly reduce any false triggering of the system. The ideal
mounting of a retro-reflective photo eye is inside an enclosure.
The ideal reflector mounting suspends it inside a 12-inch (30.48cm) long piece of 3-inch PVC conduit. Cut
the opening of the PVC conduit at a 45-degree angle to act as a drip shield. Hold the reflector against the
backside of the PVC conduit by attaching a 3-inch male connector. Do not cement the connector. This
would prevent the reflector from being reached for future cleaning. To create a mounting base, attach a
3-inch aluminum flange (electric meter hub) to the connector. This whole package can be mounted to any
flat surface.
Locate the reflector in the center of the invisible beam of infrared light to achieve the most sensitive
alignment. The beam center is determined by the following test: while holding the reflector in your hand,
slowly raise it until the beam is no longer returned and the photo eye trips. Mark this maximum height.
Now lower your hand and determine the lower limit of the infrared beam by watching for the trip point.
Mark this position as well. Repeat the same procedure for left and right at the center elevation of the
beam, as determined by the previous test. Once the four limits have been determined, either mount the
reflector in the center of the area outlined or realign the eye for the position of the reflector. If the photo
eye is realigned, be sure to perform the centering test again to verify that the reflector is truly in the center.