ViaSat 8010 Series, Руководство по подготовке площадки

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Chapter 3 - Foundation Installation (180° Mount)
Chapter 3
Foundation Installation (180° Mount)
3.1 General
The pointing accuracy of the installed antenna is determined by the stiffness
of the mount, the reflector, and the foundation. Therefore, antenna
foundation preparation is an essential part of antenna installation.
3.2 Antenna Considerations
The foundation heading is critical to the performance of the motorized
antenna and the non-motorized antenna. The foundation heading establishes
the center of azimuth travel.
Proper electrical grounding shall be provided by the installing contractor to
meet local applicable codes. Depending on local soil conditions, this may
take the form of a buried grid or a suitable copper stake. The antenna mount
shall be electrically connected to the ground.
Provisions must be made to provide suitable support for power, RF, and
control cables either by buried conduit or overhead cable tray. If conduit is
supplied, it shall be at least 4-inches (10.2 cm) in diameter with at least a 36-
inch (0.9 m) radius bend. Lightning arrestors must be provided across all
cables leaving the antenna per applicable local codes and N.F.P.A. codes.
(Refer to Section 2 or 4 for information on required operational clearances.)
3.3 Foundation Design Considerations
The antenna mount is designed to safely support the antenna in winds up to
125 mi/h (200 km/h). It is recommended that the foundation be designed for
a maximum tilt of 0.15 degrees when the 125 mi/h (200 km/h) wind loads
are applied to the antenna. It is imperative that competent engineering
assistance be engaged to assure that the foundation is properly designed for
the local site conditions and building codes. Scientific-Atlanta, Inc. does not
imply or warrant that the foundation design shown is appropriate for any
particular locality or site condition.
The loading for the above conditions is presented in Figure 4.1. The load
directional signal convention is illustrated above the tabular listing. The
foundation loading information should be used in implementing the design.
42S045D 3-1