Terrasat IBUC 3, Operation Manual

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Installation and Setup
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7-13
Engineered to Endure
6. Connect one coaxial cable between the J1 connector of the Tx 1+1 interface
module and the J1 connector of the A: side IBUC and another coaxial cable
between the J3 connector of the Tx 1+1 interface module and the J1 connector of
the B: side IBUC.
7. Connect the DC cable between the outdoor PSUI J2 connector (DC Output), as
appropriate, and the J3 connectors (DC Input) of both IBUCs.
Note:
Figure 7.2 on page 7-3 illustrates these connections.
Grounding
Antenna Recommendations
Most antenna masts are encapsulated in concrete. Typically, the mast pipe is
submerged in a a4 ft to 5 ft (1.22 m to 1.53 m) deep augured hole. This provides a
good Ufer ground. An Ufer ground encases grounding conductions in concrete.
Concrete absorbs moisture quickly, yet retains that moisture for a period of time (as
much as 15 to 30 days after rain or snow melt). The concrete’s large volume and great
area of contact with the surrounding soil enables a good transfer to the ground.
In the concrete base, an Ufer ground can be established by running a #4 gauge solid
wire or rebar and connecting with pigtails to the base of the pedestal.
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, spaced 20 ft (6.1 m) apart. The first rod should be placed close to the antenna.
The second rod should be placed towards the equipment enclosure. Connect the rods
and antenna mount with #2 gauge wire. A ground rod should be placed at the
equipment enclosure as well. If it is virtually impossible to install the ground rods,
then radials are needed. This can be accomplished by laying 10 or more lengths of 1½-
in. (3.81 cm) copper strap, at least 50 ft (15.24 m) long, in a radial fashion around the
antenna base. The straps should be buried, if possible. The hub must be interconnected
to the utility ground.
The ground configuration can vary from one location to another. It is best to measure
the soil conductivity and design a 5 Ω ground system. To protect the system from a
direct strike, a lightning rod placed 2 ft (61 cm) higher than the highest point of the
dish should be interconnected to the Ufer ground with #2 gauge copper wire.