User Guide

PMP 450 Planning Guide Grounding and lightning protection
pmp-0047 (December 2012)
2-37
Protection requirements on a high rise building
If the AP is to be mounted on a high rise building, it is likely that cable entry is at roof level (Figure 20) and the
equipment room is several floors below (Figure 21). The following additional requirements must be observed:
• The AP must be below the lightning terminals and finials.
• A grounding conductor must be installed around the roof perimeter, to form the main roof perimeter lightning
protection ring.
• Air terminals are typically installed along the length of the main roof perimeter lightning protection ring
typically every 6.1m (20ft).
• 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 20 Grounding and lightning protection on building