PS Magazine - TB 43-PS-613
PS, The Preventative Maintenance Monthly
ISSUE 613
DECEMBER 2003
To set up the SWGS, lay the
grounding cable on the ground
around the van with one end
near the power entrance panel.
Connect that end to the ground
stud in the power entrance panel.
Drive the grounding pegs fol-
lowing the route of the cable at
5-ft intervals and attach the
grounding cable.
Attach the two other connec-
tor cables by running one from a
ground peg to the front bumper
of the vehicle and the other from
a ground peg to the signal
entrance panel ground stud on
the van.
If the soil is dry, keep the areas around the SWGS pegs wet.
Inside
Inside the van, part of your grounding system is having each piece of communi-
cations equipment bonded to the shelf it sits on.
Check these bonds often to make sure movement hasn’t loosened them and that
the surface-to-surface contact is maintained.
Bonding the Van to the Generator/Trailer
If the van has a different voltage potential than the generator/trailer and you touch
both at the same time, you could get seriously injured. This is especially true if you
touch them with bare hands and provide a path for electricity to travel right across
your chest!
To prevent this, keep their voltage potential the same by bonding them together.
Run a bonding conductor (at least 6 AWG and copper) between the van and the gen-
erator/trailer.
You can make this bond at a couple of places. Connecting a grounding stud on
your generator/vehicle and a grounding stud on your van is one. Connecting
between the generator/vehicle ground rod and the SWGS is another.
Other Methods of Grounding
Getting a good ground depends on soil conditions. Sometimes you must prepare
the soil with water and chemicals to get a good ground and keep it.
Sometimes a grounding plate instead of a ground rod or a SWGS can be used.
Sometimes plumbing, buried tanks, copper grids and the metal framework of
buildings can be used.
The important things are getting a good ground; grounding all your
equipment to the earth; bonding your equipment to other equipment;
doing it safely; and keeping it from becoming a hazard to foot traffic.
E
ven your AT-1011, the 32-ft whip antenna used with the AN/PRC-150 family of
radios, is subject to laws.
One of those is Coulomb’s Law, “The force between two charges is equal to the
product of the two charges divided by the square of the distance between them.”
What that means in English (and soldier) is a static charge can accumulate on
your antenna when sand blows across it or
before a rain or electrical storm.
That charge makes a high voltage elec-
trostatic field that when discharged can fry
the circuits in the RF-382 antenna coupler.
Since the radio is procured commercial-
ly, the manufacturer is sending a bleeder
resistor kit to slowly discharge any surface
charge build-up on the antenna.
PS 613
45
so, you see…
the force between
two charges is equal
to the product of
the two charges
divided by the square
of the distance
between them.
what does
that mean?
rememember
what happened
to the radio,
back in the
desert?
“sand blew
across the
antenna…
…and that fried
the circuits in
the coupler.”
RF-382 antenna coupler can get fried
Connect end to
ground stud in
power entrance
panel
Surface wire
grounding
system in
place
zoinks!
613. 44-45 (C)
11/3/03
4:04 PM
Page 1
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