Wavespan Stratum 100, Installation And Maintenance Manual, Page: 16 / 67

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Installation Stratum 100 Installation and Maintenance Guide
For masts 1.9 to 2.5 inches in diameter use 3.5 inch long hex-head bolts for each yoke. For
masts 2.5 to 3.9 inches in diameter use the 4.5 inch long hex-head bolts.
Use a safety rope, or second person to hold the ODU in position on the mast, resting on the
rubber collar as shown. Install the top clamping yoke first. Install the bottom yoke last.
Note : Be careful not to drop the ODU. The weather seals protecting the antenna and microwave
transceiver can be damaged.
Visually aim the antenna as precisely as possible in azimuth and elevation. Use a map and
compass to set the correct direction. Tighten both yokes and elevation arms securely until you
are ready for antenna aiming.
Position mount on clamp, install top yoke first
Install bottom yoke last
Grounding the ODU and Mast
In Section 7.1 you connected the ODU ’s ground stud to the antenna mount, which in turn must
be grounded through the metallic mast. These important ground connections provide a short
circuit path for static that could build up on the
ODU
, potentially damaging the microwave
transceiver or degrading performance. This protection depends on the metallic mast or
antenna support being properly connected to an earth ground.
A building’s electrical system ground is typically not a good earth ground because it can have
high currents flowing through it that result from an imbalance in the distribution of the single-
phase load throughout a building. Ground loops can result if two pieces of equipment are
grounded to the electrical system ground and if there is a voltage difference between the
ground points. For electrical protection it is important that the Stratum 100 Indoor and
ODU
s
are grounded to an earth ground that does not have a voltage difference between the Indoor
and
ODU s.
Lightning Protection
Damage to your Stratum 100 Indoor or ODUs caused directly or indirectly by lightning
is not covered under the manufacturer’s warranty.
If your ODU is located where nearby or direct lightning strikes are possible, especially on the
top of a tall building, a lightning rod and grounding system installed by a licensed
professional are highly recommended. In addition, the use of lightning arrestors in the two
coaxial cables (located in-line at the cable entry point to the building or at the rear of the IDU)
with an earth ground is highly recommended. Wavespan and its authorized resellers can
recommend suppliers of suitable coaxial lightning arrestors with Type-N connectors and
ground posts.
The purpose of in-line lightning arrestors in the coaxial cables is to protect the IDU from high
voltages induced by nearby lightning or a direct lightning strike at the
ODU . The ideal
location for in-line lightning arrestors would be at the point where the coaxial cables enter the
building. This involves separate cables from the
ODU to the point of entry, and additional
cables from there to the IDU. The next best approach is to locate in-line lightning arrestors at
the rear of the IDU, with a separate heavy-guage (#10 or #8) earth ground running directly
from the lightning arrestors to a proper grounding system.