Chamberlain LiftMaster PROFESSIONAL SECURITY+ 3255-2CM Manuel Du Propriétaire page 18

MOUNTING AND WIRING THE SAFETY REVERSING
SENSORS
• Slide a 1/4"-20x1/2" carriage bolt head into the slot on
each sensor. Use wing nuts to fasten sensors to
brackets, with lenses pointing toward each other across
the door. Be sure the lens is not obstructed by a bracket
extension (Figure 5).
• Finger tighten the wing nuts.
• Run the wires from both sensors to the opener. Use
insulated staples to secure wire to wall and ceiling.
• Strip 7/16" (11 mm) of insulation from each set of wires.
Separate white and white/black wires sufficiently to
connect to the opener quick-connect terminals. Twist
like colored wires together. Insert wires into quick-
connect holes: white to white and white/black to grey
(Figure 6).
ALIGNING THE SAFETY REVERSING SENSORS
• Plug in the opener. The indicator lights in both the
sending and receiving eyes will glow steadily if wiring
connections and alignment are correct.
The sending eye amber indicator light will glow regardless
of alignment or obstruction. If the green indicator light in
the receiving eye is off, dim, or flickering (and the invisible
light beam path is not obstructed), alignment is required.
• Loosen the sending eye wing nut and readjust, aiming
directly at the receiving eye. Lock in place.
• Loosen the receiving eye wing nut and adjust sensor
until it receives the sender's beam. When the green
indicator light glows steadily, tighten the wing nut.
Figure 6
Bell Wire
Safety Reversing Sensor
Finished
Ceiling
Safety Reversing Sensor
Invisible Light Beam
Protection Area
Figure 5
Carriage Bolt
1/4"-20x1/2"
TROUBLESHOOTING THE SAFETY REVERSING
SENSORS
1. If the sending eye indicator light does not glow steadily
after installation, check for:
• Electric power to the opener.
• A short in the white or white/black wires. These can
occur at staples, or at opener connections.
• Incorrect wiring between sensors and opener.
• A broken wire.
2. If the sending eye indicator light glows steadily but the
receiving eye indicator light doesn't:
• Check alignment.
• Check for an open wire to the receiving eye.
3. If the receiving eye indicator light is dim, realign either
sensor.
NOTE: When the invisible beam path is obstructed or
misaligned while the door is closing, the door will reverse.
If the door is already open, it will not close. The opener
lights will blink 10 times. See page 16.
Connect Wire to
Opener Quick-Connect Terminals
Bell Wire
18
Wing Nut
1/4"-20
Lens
1. Strip wire 7/16"
(11 mm)
7/16" (11 mm)
2. Twist like colored
wires together
3. To release or insert
wire, push in tab with
screwdriver tip
Red White Grey
Quick-Connect Terminals