Table of Contents
Advertisement
3. Grounding and lightning protection
Mounting the GPS receiver on a metal tower or mast
For mast or tower installations, the following additional requirements must be met:
•
The equipment must not be mounted any higher than is necessary to receive an
adequate signal from four GPS satellites.
•
The equipment must be protected by a nearby lightning air terminal that projects
further out from the tower than the GPS receiver module.
•
The equipment must be lower than the top of the tower or its lightning air terminal.
•
The metal tower or mast must be correctly grounded.
•
A grounding kit must be installed at the first point of contact between the drop cable
and the tower, near the top.
•
A grounding kit must be installed at the bottom of the tower, near the vertical to
horizontal transition point, bonded to the tower or its ground bar (TGB).
•
If the tower is greater than 61 m (200 ft
be installed at the tower midpoint, with additional kits as necessary to reduce the
distance between ground kits to 61 m (200 ft) or less.
•
In high lightning prone geographical areas, additional ground kits should be
installed at spacing between 15 to 22 m (50 to 75 ft
towers taller than 45 m (150 ft.).
A schematic example of a mast or tower installation is as follows:
Tower Ground Bar (TGB)
phn-1613_008v000 (Jun 2011)
in height, an additional grounding kit must
)
GPS receiver
First point of contact with tower
Mid-point of tower
Bottom of tower
External Ground Bar (EGB)
Ground ring
PTP-SYNC Installation Guide
. This is especially important on
)
CAT5e cable: gel-filled, shielded
with copper-plated steel
CAT5e cable: unscreened or screened
Ground cable
Ground bus conductor
Rack Ground Bar (RGB)
Master Ground Bar (MGB)
PTP-SYNC
Lightning Protection
Unit (LPU)
To PIDU
Plus
To ODU/LPU
on mast
Equipment rack
Page 15
Advertisement
Table of Contents
