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TimeProvider 2300/2700 User’s Guide
098-00564-000 Revision A3 – July, 2013
Appendix C Installing GNSS Antennas
GNSS Antenna Installation
Developing a Grounding Scheme
In addition to determining where to locate and mount the antenna and cabling, you
should develop a grounding scheme. The purpose of the grounding scheme is to
provide some protection against voltage surges and static discharge. If lightning
arrestors are used, they also need to be connected to the perimeter ground system
or to the bulkhead entrance panel that is connected to the perimeter ground system.
In general, follow local building codes when selecting a grounding scheme, wire
size, and installation.
Use #6 AWG (16 mm
2
) copper ground wire or larger, depending on the distance
to the earth ground electrode. Refer to your local electrical codes for specific
details. In most cases, #1/0 AWG (50 mm
2
) ground wire will maintain 1/10 the
resistance of the coaxial shield.
Connect lightning arrestors, if part of the grounding scheme, to earth ground
through a conductor.
Never connect antenna systems to the same earth ground connector as heating
and cooling systems, elevator or pump motors, or other motors or machinery
which can induce noise in the antenna system.
Antenna Installation Tools and Materials
These standard tools and materials are not supplied in the antenna kit, but may be
required for installing the GNSS antenna.
Caution:
To ensure proper grounding, observe these precautions
when installing the antenna:
Allow no sharp bends in the ground conductors. The ground
conductor must have a 9.1 m (30-ft.) radius for any bends made.
Ensure that no painted surface insulates the lightning arrestor or
grounding clamps.
Ensure that ground conductors are bonded to the metal enclosure
box (if used) and do not enter through an access hole.
Do not use soldered connections for grounding purposes.
Secure all grounding connections with mechanical clamp type
connectors.
Note:
Larger ground conductors provide better transient elimination;
that is, the larger the ground conductor, the less likely the chance of
transients.
Note:
Do not
connect the outside lightning arrestor ground to the
inside equipment rack ground. Doing so can defeat the protection
afforded by the lightning arrestor.