TRIAX Multimedia Main Catalogue

Terrestrial antennas
Mast calculation
The conditions detailed in the DE/EN 60728-11
must be observed when mounting antennas on
a mast.
The sum of the moments resulting from the
intrinsic moment of the mast and the bending
moments caused by the mount ed antennas must
not exceed the maximum permitted bending
moments of the mast itself.
The bending moment caused by an antenna is
calculated by the following formula:
Wind load (N) x distance (m)
= bending moment (Nm)
The distance and bending moment refer to the top
clamping point. Bending moments in excess of
1650 Nm require proof of structural stability.
Wind load x distance = bending moment
1)
16 N x 3,6 m = 57.6 Nm
2)
56 N x 2,8 m = 156.8 Nm
3)
96 N x 2,0 m = 192,0 Nm
4)
619 N x 1 m = 619,0 Nm
Total bending moment of the antennas 1025,4 Nm
The total bending moment for the antenna at 1025.4
Nm is less than the usable bending moment for the
antenna to be mounted of 1250 Nm.
Therefore the intended configuration is permitted!
1)
FM Omni
2)
VHF ch. 8 - 8 elem.
3,6 m
3)
UNIX 52
Mast Ø42 mm
2,8 m
4)
Triax TD 100
2,0 m
1,0 m
0,9 m
In accordance with DIN EN 50083-1
the clamped length of the mast must
be at least 1/6 of the mast length
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