Chamberlain 1240R - 1/4HP - Manual (Page 23)

23
Carriage Bolt
1/4"-20x1/2"
Lens
Wing Nut
Figure 5 MOUNTING AND WIRING THE SAFETY 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 1/4" (6 mm) of insulation from each set of
wires. Separate white and white/black wires
sufficiently to connect to the opener terminal
screws: white to 2 and white/black to 3 (Figure 6).
ALIGNING THE SAFETY 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.
TROUBLESHOOTING THE SAFETY 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 terminal 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. (If bulbs are not
installed, 10 clicks can be heard.) See page 21.
Invisible Light Beam
Protection Area
Sensor
Sensor
Connect Wire to
Opener Terminal screws
Bell Wire
Finished Ceiling
OPENER TERMINAL SCREWS
Sensor
Connections
Door Control
Connections
(dotted line)
1 2 3
Bell Wire
Figure 6