PTP 250 User Guide
Grounding and lightning protection
phn-2182_002v000
May 2011
2-17
Protection requirements on a high rise building
If the ODU is to be mounted on a high rise building, it is likely that cable entry is at
roof level (
Figure 2-5
) and the equipment room is several floors below (
Figure 2-6
). In
addition to the general protection requirements (above), the following requirements
must be observed:
x
The ODU must be below the lightning terminals and finials.
x
A grounding conductor must be installed around the roof perimeter, to form the
main roof perimeter lightning protection ring.
x
Air terminals are typically installed along the length of the main roof perimeter
lightning protection ring typically every 6.1 m (20 ft).
x
The main roof perimeter lightning protection ring must contain at least two down
conductors connected to the grounding electrode system. The down conductors
should be physically separated from one another, as far as practical.
Figure 2-5
Grounding and lightning protection on building
Air terminal (finial)
Tower grounding
conductor
Building ground ring
AC
service
ODU
To equipment area
CAT5e cable: gel-filled, shielded
with copper-plated steel
PTP 250 ground cables
Building ground system
Summary of Contents for Motorola PTP 250
Page 20: ...List of Tables phn 2182_002v000 xiv May 2011 ...
Page 30: ......
Page 80: ...Data network planning Chapter 2 Planning considerations phn 2182_002v000 2 22 May 2011 ...
Page 126: ...Notifications Chapter 4 Reference information phn 2182_002v000 4 36 May 2011 ...
Page 234: ...Testing the radio link Chapter 8 Troubleshooting phn 2182_002v000 8 14 May 2011 ...
