Motorola PTP 800, User Manual

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User Guide: PTP 800 Licensed Ethernet Microwave Grounding and lightning protection
phn-1478_005v000
Apr 2010
2-9
x
The LPU should be bonded to the tower (or main grounding system) using
the 600mm long 16mm
2,
#6AWG cable supplied in the accessory kit.
Protection requirements for a mast or tower installation
If the equipment (ODU or antenna) is to be mounted on a metal tower or mast, then
in addition to the general protection requirements (above), the following
requirements must be observed:
x
The equipment must be lower than the top of the tower or its lightning
terminal and finial.
x
The metal tower or mast must be correctly grounded.
x
A grounding kit must be installed at the first point of contact between the
drop cable and the tower, near the top.
x
A grounding kit must be installed at the bottom of the tower, near the vertical
to horizontal transition point. This grounding kit must be bonded to the tower
or tower ground bus bar (TGB) if installed.
x
If the tower is greater than 61 m (200 ft
)
in height, an additional grounding kit
must be installed at the tower midpoint. Additional ground kits must be
installed as necessary to reduce the distance between ground kits to 61 m
(200 ft) or less.
x
In high lightning prone geographical areas, additional ground kits should be
installed at spacing between 15 to 22 m (50 to 75 ft
)
. This is especially
important on towers taller than 45 m (150 ft).
x
If a CAT5e (or other) cable is already cross-bonded to the mast or tower, the
same cross bonding points on the mast or tower must be used for the IF
cable.
Figure 2-5 shows the protection requirements for an ODU mounted on a metal
tower or mast.