Best Practices Trackside Tower and Antenna Installation - Railroad ...

Best Practices
Trackside Tower and Antenna Installation
Rev April 12, 2011

PTC and ARES Antenna
Towers
•Maximum distance from building
is 25 feet
Separation between
Antennas
•Prefer 25 feet
•Minimum 10 feet, if less than
10ft a160/200 MHZ filter is
required
Turn base so when tower is
tipped down antenna will be
in a flat spot.

Make sure you know
the conversion from
PSI to Foot Pounds for
the machine you are
operating.
The drilled pier foundation is designed to minimize soil disturbance and time involved for installation compared to
other types of foundations. The minimum requirements for properly installed helical pier are 1) to achieve
penetration so the pier’s top base plate is 8” or less above grade and 2) achieve a minimum torque value of 3,000
foot-pounds. A maximum torque value of 15,000 foot-pounds should be used. In the event the helical pier
foundations cannot be installed per the standard procedure above, one of the following Alternative Procedures
should be used. (See EMI Helical Pier Installation and Maintenance Instructions)

Backfill the helical pier
then cap with premix
concrete.

Grind area for cadweld
Tower Base Grounding

Attach mold to tower using
clamp. This mold is designed to
do the cadweld while the tower
base is standing.
ERICO Cadweld Parts
Mold & Handle
L160 Handle Clamp
VBC-1G mold used to attach #6
solid copper to base of tower
B134 Vertical Surface Mold
Support C-clamp
#65 shot comes in boxes of 20
Mold & slag cleaning
T394 Mold cleaning brush
B-136-A Slag removal spade
Mold Sealer
T403 Mold sealer when mold
starts to wear

Spray cadweld and tower with
cold galvanize covering area
where the galvanize was
removed.
DO NOT USE SIGNAL GRAY
SPRAY PAINT!!!

Ground Rods
Ground rods at tower should be a minimum of 24”
below top of soil. If frost line is deeper than 24” prefer
you to go deeper. Ground wire and conduit can be ran
in same trench.
Conduit (liquid tight) should be the same depth.

Halo around helical pier and ground wire running to building
halo

While backfilling compact soil using
tamper.
http://www.astm.org/SEARCH/sites
earch.html?query=soil+compact

12”
Completed Helical Pier and Tower Base Install

Operational Procedure
Acceptance Criteria
(OPAC)
Resistance to ground at
tower ring 5 Ohms (less than)
Current flow to ground at
tower ring (Amps) .2 amps
(less than)
Resistance to ground at
building ring (Ohms) 5 ohms
all legs (less than)
Current flow to ground at
building ring (Amps) all legs
.2 amps (less than)

Mid span tool for removing sheathing from LMR600 coax for the ground connection
Part # GST-600A

Ground Clamp
• Strip sheathing off LMR600 coax
• Attach ground kit with pigtail to
right side of coax
• Apply mastic by wrapping from
bottom of ground clamp to top
• Wrap with vinyl tape; start wrap
at bottom of clamp, wrap to top
then down, then last wrap should
be bottom to top to create
shingle effect. Same procedure
for the top of the tower.

Dual Mechanical
Ground Tab
• Grind galvanize off tab for
ground connection
• Measure ground wire; gradual
curve to tab.
• Slide heat shrink on wire, crimp
on ground lug. Heat the heat
shrink after you crimp on the lug
or after lug is attached to the
ground tab.
• Put oxidation grease on ground
tab then attach lug to tab.
• Spray cold galvanize on lug and
tab
• DO NOT USE SIGNAL GRAY
SPRAY PAINT!!!

Coax Ground at Base of Tower: Both are acceptable curves for the ground wire going to the ground tab on the
tower.
Right picture is missing the cold galvanize spray.

Installer put the oxidation grease on
the dual mechanical tab and is
measuring the ground
wire length.

PTC Latest Mods for Top of Tower
� 6 inch pigtail coming from PTC antenna
� 5/8 coax 12” to 18” maintenance loop
� Green Identification tape on PTC antenna

Tape bottom of hoisting grip

Ground lug will be at this angle.
You can use either hole on tab.
Break the first hole off lug, you
can see the indention where break
will occur
Don’t forget the heat shrink

Grind galvanize off ground tab. Grind
only the hole you will be using.
Apply oxidation grease
Connect lug
Spray cold galvanize on lug and ground
tab.
Ground wire should be
shortest distance from ground
clamp to tower ground tab.
Wire should be straight or
slight curve.

Example of a completed ground connection at the top of the tower

Ground will be attached at these points
Single loop:
LMR600 comes out of
tower and is coiled going
clockwise.
6ft pigtail on the antenna
goes counter clockwise
and connectors meet in
the middle next to the
mounting pipe.

Antenna will point towards track when tower is raised.
Mount bracket clamp at
least 2” below top of pipe

If no hook is provided, attach the grip to the bottom U-bolt of the antenna mast.

New Building for Control Point
Cut wood out next to rack so you can drill
holes through the floor for the liquid tight
entering the building
See signal engineering drawing for location.
See next slide

Wood removed, holes drilled, liquid
tight connected to the floor and coax
ran into building.
Buildings will start coming with holes
drilled and a bracket mounted for
polyphasers.

Completed install With:
Weather Caps
8” standoffs
Polyphasers
The floor is the ground plane so
ground wire is not needed.
PTC coax is ran closest to
board.
PTC
ARES or ATCS

New Building for
an Intermediate

Use self tapping screws to
fasten plate to floor

Operational Procedure
Acceptance Criteria
(OPAC)

VIC 100 GPS Antenna and Bracket

Ground wire is not needed when
bracket is attached to a metal building.
The building provides the ground
plane.

Mark IV GPS Antenna and Bracket