Chamberlain 3840 Garage Door Opener User Manual


 
11
INSTALLATION STEP 4
Install The Protector System
®
The safety reversing sensor must be connected and
aligned correctly before the garage door opener will
move in the down direction.
IMPORTANT INFORMATION ABOUT THE SAFETY
REVERSING SENSOR
When properly connected and aligned, the sensor will
detect an obstacle in the path of its electronic beam. The
sending eye (with an amber indicator light) transmits an
invisible light beam to the receiving eye (with a green
indicator light). If an obstruction breaks the light beam
while the door is closing, the door will stop and reverse to
full open position, and the opener lights will flash 10 times.
The units must be installed inside the garage so that the
sending and receiving eyes face each other across the
door, no more than 6" (15 cm) above the floor. Either can
be installed on the left or right of the door as long as the
sun never shines directly into the receiving eye lens.
The mounting brackets are designed to clip onto the track
of sectional garage doors without additional hardware.
If it is necessary to mount the units on the wall, the
brackets must be securely fastened to a solid surface such
as the wall framing. Extension brackets (see accessories)
are available if needed. If installing in masonry
construction, add a piece of wood at each location to
avoid drilling extra holes in masonry if repositioning is
necessary.
The invisible light beam path must be unobstructed. No
part of the garage door (or door tracks, springs, hinges,
rollers or other hardware) may interrupt the beam while
the door is closing.
Be sure power is not connected to the garage door opener
BEFORE installing the safety reversing sensor.
To prevent SERIOUS INJURY or DEATH from a closing garage
door:
• Correctly connect and align the safety reversing sensor. This
required safety device MUST NOT be disabled.
• Install the safety reversing sensor so beam is NO HIGHER
than 6" (15 cm) above garage floor.
Invisible Light Beam
Protection Area
Safety Reversing Sensor
6" (15 cm) max. above floor
Safety Reversing Sensor
6" (15 cm) max. above floor
Facing the door from inside the garage