Cambium Networks PMP 450d Series, Руководство пользователя

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Chapter 3: System planning Site planning
Page 3-14
Table 63 PMP/PTP 450 Series wind loading (lb force)
Type of ODU Max surface area
(square feet) Wind speed (miles per hour)
100 105 110 115 120
External 60º sector
antenna – 2.4 GHz
AP 2.9 122 134 147 161 175
External 60º sector
antenna – 5 GHz AP 0.71 29.8 33 37 39 43
External 90º sector
antenna – 5 GHz AP 0.89 37 41 45 49 54
SM 0.29 12 13 15 16 18
Integrated High-
Gain, Ruggedized 1 42 46 51 56 60
Integrated Dish 1.49 63 69 76 83 90
Drop cable grounding points
To estimate how many grounding kits are required for each drop cable, refer to the site installation
diagrams (
Figure 36 , Figure 37 and Figure 38 ) and use the following criteria:

The drop cable shield must be grounded near the ODU at the first point of contact between the
drop cable and the mast, tower or building.

The drop cable shield must be grounded at the building entry point.
For mast or tower installations ( Figure 36 ), use the following additional criteria:

The drop cable shield must be grounded at the bottom of the tower, near the vertical to
horizontal transition point. This ground cable must be bonded to the tower or tower ground
bus bar (TGB), if installed.

If the tower is greater than 61 m (200 ft
)
in height, the drop cable shield must be grounded at
the tower midpoint, and at additional points as necessary to reduce the distance between
ground cables to 61 m (200 ft) or less.

In high lightning-prone geographical areas, the drop cable shield must be grounded at spacing
between 15 to 22 m (50 to 75 ft
)
. This is especially important on towers taller than 45 m (150 ft).
For roof installations ( Figure 38 ), use the following additional criteria:

The drop cable shield must be bonded to the building grounding system at its top entry point
(usually on the roof).

The drop cable shield must be bonded to the building grounding system at the entry point to
the equipment room.