Chamberlain 772E, Installation Manual, Page: 7 / 56

INITIAL OPERATION AND TESTING OF PHOTOCELLS
• Open the door with the remote control or a switch.
• Place an obstacle between the transmitter and receiver to interrupt the infrared
beam.
• Operate the remote control or switch again to start the closing process.
The garage door must not close now, since the infrared beam is interrupted.
There is a red LED below the housing of the 772E (which is not visible with
closed housing), which flashes when the infrared beam is interrupted, thus
indicating that there is an obstacle between the transmitter and receiver, or that
the lenses are not aligned correctly.
If the garage door closes even the
infrared beam is interrupted by an obstacle or if the transmitter and receiv-
er are not aligned correctly, the system must be checked immediately by
an authorised technician.
TROUBLESHOOTING
The LED indicator on transmitter and/or receiver does not light up after installa-
tion. Check the following points:
• Power supply of the system
• Potential short-circuit
• Incorrect cable connection between sensor and controller
• Broken or missing cable
• Polarity of the cables are interchanged
TECHNICAL DATA
Protection class: IP44
Temperature range: - 20°C + 70°C
Range: 15 m
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