User's Manual Part 1

Chapter 3: System planning Site planning
ODU wind loading
Ensure that the ODU and the structure on which it is mounted are capable of withstanding the
prevalent wind speeds at a proposed PTP 650 site. Wind speed statistics should be available from
national meteorological offices.
The ODU and its mounting bracket are capable of withstanding wind speeds of up to 323 kph
(200 mph).
Wind blowing on the ODU will subject the mounting structure to significant lateral force. The
magnitude of the force depends on both wind strength and surface area of the ODU. Wind loading
is estimated using the following formulae:
Force (in kilogrammes) = 0.1045aV
2
Where:
Is:
a surface area in square meters
V wind speed in meters per second
Force (in pounds) = 0.0042Av
2
Where:
Is:
A surface area in square feet
v wind speed in miles per hour
Applying these formulae to the PTP 650 ODU at different wind speeds, the resulting wind loadings
are shown in Table 28 and Table 29.
Table 28
ODU wind loading (Kg)
Type of ODU
Max surface area
(square meters)
Wind speed (meters per second)
30
40
50
60
70
Integrated 0.130 12 Kg 22 Kg 34 Kg 49 Kg 66 Kg
Connectorized 0.093 9 Kg 16 Kg 24 Kg 35 Kg 48 Kg
Table 29
ODU wind loading (lb)
Type of ODU
Max surface area
(square feet)
Wind speed (miles per hour)
80
100
120
140
150
Integrated 1.36 37 lb 57 lb 82 lb 146 lb 229 lb
Connectorized 1.00 27 lb 42 lb 61 lb 108 lb 168 lb
Page
3-11