ZyXEL Communications ZyAIR G-5100 User Manual page 237

Wind
Any system components mounted outdoors will be subject to the effects of wind. It is
important to know the direction and velocity of the wind common to the site. The mounting
structure must be able to withstand these forces as well as protect against damage to the
outdoor wireless device components.
Antenna designs react differently to wind forces, depending on the location. This is known as
wind loading. Most antenna manufacturers will specify wind loading for each type of antenna
manufactured.
Temperature Ranges
Temperature can adversely affect the radio link when phenomena such as temperature
inversion or very still air accompanied by stratification occur
See the section on Fog for further detail.
Lightning
The potential for lightning damage to radio equipment should always be considered when
planning a wireless link. There are a variety of lightning protection and grounding devices,
whether located inside or outside the site, which could potentially be damaged by a lightning
strike.
Lightning protection requirements are based on the level of site exposure, the cost in the event
of a link downtime, local building codes and electrical codes. If the link is critical and the site
is in an active lightning area, attention to thorough lightning protection and grounding is
critical.
Lightning Protection
To provide adequate lightning protection,
• Install antennas in locations that are unlikely to receive direct lightning strikes.
• Install lightning rods to protect antennas from direct strikes.
• Make sure that cables and equipment are properly grounded to provide low-impedance
paths for lightning currents.
• Install surge suppressors on telephone lines and power lines.
Interference
An important part of planning a site for your outdoor wireless device is the avoidance of
interference.
Appendix G Outdoor Site Planning
ZyAIR G-5100 User's Guide
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