Chamberlain ELITE R900 Instruction Manual page 7

W A R N I N G S A N D P R E C A U T I O N S
F) For a gate operator utilizing a non-contact sensor such as a photo beam:
1) See instructions on the placement of non-contact sensor for
each type of application.
2) Care shall be exercised to reduce the risk of nuisance tripping,
such as when a vehicle trips the sensor while the gate is still
moving.
3) One or more non-contact sensors shall be located where the
risk of entrapment or obstruction exists, such as the perimeter
reachable by a moving gate or barrier.
G) For a gate operator utilizing a contact sensor such as an edge sensor:
1) A hardwired contact sensor shall be located and its wiring arranged
so that the communication between the sensor and the gate operator
is not subjected to mechanical damage.
2) A wireless contact sensor such as the one that transmits radio
frequency (RF) signals to the gate operator for entrapment
protection functions shall be located where the transmission of
the signals are not obstructed or impeded by building structures,
natural landscaping or similar obstruction. A wireless contact sensor
shall function under the intended end-use conditions.
3) One or more contact sensors shall be located on the inside and
outside leading edge of a swing gate. Additionally, if the bottom edge
of a swing gate is greater than 6 inches (152 mm) above the ground at
any point in its arc of travel, one or more contact sensors shall be
located on the bottom edge.
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