Globalstar GSP-2800, Руководство по установке

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Ground the QGFSP
23
Lightning Protection
• Connect the RAU ground wire to the RAU chassis using the
ground screw on the lower rear face of the RAU. The screw holds
the lug of the ground wire in rigid metal-to-metal contact with
the surface of the chassis surrounding the screw head.
• If the RAU is mounted on a building that is not lightning
protected or on a pole, run the grounding wire from the RAU
down the pole next to the RAU cable and route it past the
junction box. Then bolt it to a grounding rod; that is, a rod
specifically designed to ground in this situation. Refer to Figure
27 on page 38 and Standard practices for grounding on page 36.
Connect the 0.5 meter (1.6 foot) #6 AWG ground wire from the
junction box to the RAU ground cable using the C-type
compression tap and a crimping tool.
• If the RAU is mounted on a building that is lightning protected,
run the primary grounding cable from the RAU past the junction
box, then attach the junction box ground wire to the building
lightning ground rod within the ground rod pit (see Figure 27 on
page 38). Alternatively, run the RAU primary ground wire to its
own separate ground rod. Connect the junction box ground wire
to the primary ground cable using the C-type compression tap.
Note
For almost all installations, QUALCOMM recommends using
#6 AWG copper grounding cable for the RAU ground cable and
for the ground wire securing the junction box grounding screw
to the RAU primary ground cable (see Figure 17 on page 22). An
C-type compression tap is recommended to bond the junction
box ground wire to the RAU primary grounding cable. The
junction box ground wire should be as short as possible.
The total length of cable from the junction box to earth ground
must be less than 3.5 meters (0.5 meters from the junction box
to the RAU ground cable plus 3 meters [10 feet] from the tap to
the ground rod). If this is simply not possible for a particular
installation, the RAU should be protected by a primary
lightning protection system (lightning rod).
Table 10. Grounding elements
*
Item Name Description and Purpose
A Ground terminal Connection point on
junction box for #6
grounding wire.
B Ground lug Connection point on RAU
for primary grounding
cable.
C #6 AWG primary ground
cable Connects RAU to ground
rod.
D
C-type compression tap
Secures #6 ground cable to
primary ground cable.
E #6 junction box ground wire Connects junction box to
RAU through connection to
primary grounding cable.
F Ground wire/ground rod
connection Hardware used to connect
primary grounding cable.
See Figure 2 on page 21.
G Ground Rod Device for grounding. It is
buried in the ground 2.4 to
3 meters (8 to 10 feet) deep.
*
See Figure 19 on page 25 and Appendix A. Standard practices for
grounding.