Cambium Networks cnReach N500, User Manual

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cnReach N500 User Guide
InstallationSafety
phn-4673_002v000 (March 2018)
5-4
Site grounding system
Confirm that the site has a correctly installed grounding system on a common ground ring with access
points for grounding cnReach equipment.
If the outdoor equipment is to be installed on the roof of a high building, confirm that the following
additional requirements are met:
• A grounding conductor is installed around the roof perimeter to form the main roof perimeter
lightning protection ring.
• Air terminals are installed along the length of the main roof perimeter lightning protection ring,
typically every 6.1m (20ft).
• The main roof perimeter lightning protection ring contains at least two down conductors connected
to the grounding electrode system. The down conductors should be physically separated from one
another, as far as practical.
Grounding cable installation methods
To provide effective protection against lightning induced surges, observe these requirements:
• Grounding conductor runs are as short, straight and smooth as possible, with bends and curves kept
to a minimum.
•
Grounding cables must not be installed with drip loops.
• All bends must have a minimum radius of 200 mm (8 in) and a minimum angle of 90°. A diagonal
run is preferable to a bend, even though it does not follow the contour or run parallel to the
supporting structure.
•
All bends, curves and connections must be routed towards the grounding electrode system, ground
rod, or ground bar.
• Grounding conductors must be securely fastened.
•
Braided grounding conductors must not be used.
• Approved bonding techniques must be used for the connection of dissimilar metals.
Siting the uGPS and antennas
External antennas and GPS receivers are not designed to survive direct lightning strikes. For this reason
they must be installed in Zone B as defined in Lightning protection zones covered in the previous
section.
Thermal Safety
The ODU enclosure may be hot to the touch when in operation. The ODU must not be operated in
ambient temperatures exceeding 40°C unless mounted in a Restricted Access Location.
Warning
Do not install the cnReach radio in a location where the ambient temperature could exceed
40°C unless this is a Restricted Access Location as defined by EN 60950-1.