User's Manual

PTP 250 User Guide Site planning
phn-2182_002v000
May 2011
2-5
Maximum cable lengths
The maximum permitted lengths of interface cables in PTP 250 installations are
specified in Table 2-1.
Table 2-
1 Maximum cable lengths
Interface type Interface Maximum
length
Ethernet power
and data
ODU to network terminating
equipment.
100 m (330 ft)
Wind loading
Ensure that the supporting structure will not be prone to excessive wind loading.
Antennas and equipment mounted on towers or buildings will subject the mounting
structure to significant lateral forces when there is appreciable wind. Antennas are
normally specified by the amount of force (in pounds) for specific wind strengths. The
magnitude of the force depends on both the wind strength and size of the antenna.
The ODU, with or without the integral antenna, is essentially a flat structure. The
magnitude of the lateral force can be estimated from surface area and wind speed.
Calculation of lateral force (metric)
The magnitude of the lateral force can be estimated from:
Force (in kilograms) = 0.1045aV
2
Where: Is:
a surface area in square meters
V wind speed in meters per second