Terrasat Rx 1+1, Руководство по эксплуатации

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Installation
Grounding
Terrasat recommends the following grounding and lightning protection:
• Cable Shielding
Shield currents can be eliminated with proper techniques. A grounding strap at the
end of the coaxial and data cables should be connected to the ground lug at the
antenna base with a #4 gauge copper wire. This provides a path of least resistance
prior to entering the electronic equipment.
• AC
The best way to protect the equipment is to have two protectors. The first is the
power mains protector that is mounted directly across the mains in the breaker
box. The second should be mounted or grounded directly at the base or hub of the
antenna or at the 19-in. rack.
• Data and Control Lines
The I/O lines can deliver surge current to the equipment and should also be
protected.
• Electrical Grounding
Grounding of the Rx 1+1 interface module is recommended to prevent possible
damage from lightning and/or other induced electrical surges. Terrasat
recommends the use of 3/0 or 4/0 AWG stranded copper wire for bonding the
Rx 1+1 interface module to the earth ground (grounding rod), using the most
direct or shortest route.
Antenna Recommendations
Most antenna masts are encapsulated in concrete. Typically, the mast pipe is
submerged in a 4 ft to 5 ft (1.22 m to 1.53 m) deep augured hole. This provides a good
Ufer ground. A Ufer ground, in this case, is defined such that concrete absorbs
moisture quickly and loses that moisture slowly (as much as 15 to 30 days after rain or
snow melt). The mineral properties of concrete and their inherent pH means that
concrete has a supply of ions to conduct current. The soil around concrete becomes
“doped” by the concrete and as a result, the pH of the soil rises. The moisture present
in the concrete, in combination with the “doped” soil, makes a good connector of
electrical energy. The concrete’s large volume and great area of contact with the
surrounding soil allow a good transfer to the ground,
In the concrete base, a Ufer ground can be established by running a #4 gauge solid
wire or rebar and connecting to the base of the pedestal with pigtails.
The Ufer ground is only one step in proper grounding. The Ufer ground should be
augmented with coupled pairs of 10
ft (3.05 m) rods, placed 20 ft (6.1 m) into the
ground and spaced 20 feet (6.1 m) apart. The first rod should be placed close to the