Rain Bird WS-PRO, Installation, Maintenance And Troubleshooting Manual

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ground rather than go to the electronic
components. From this you can see that
it is also important to maintain a “Good
Ground” at ALL times.
BENTONITE CONTACT: In using
grounding rods we are depending upon
the “contact” of the surface of the rod to
the soil. The greater the contact the
better chance we have of obtaining a
“good” ground. If you are in a soil type
that you know will not give good surface
contact with the rod, you may want to
consider drilling a 4” to 6” diameter hole
in which to place the ground rod. You
can then back fill around the rod with
Bentonite or other similar material that
is very dense and in this way increase
the contact of the rod with the soil.
ROCKY CONDITIONS: In areas
where you are unable to drive a rod or to
bore a hole for a rod, you may need to
consider laying the rods horizontal 12
inches or so below the surface on a good
6” deep bed of soil or Bentonite. Again
rods should be 8’-0” apart and tied
together with #10 gauge or larger bare
copper wire at both top and bottom of
the rods to form a grid.
ROCK LAYER: Where a rock layer is
found under a shallow layer of soil, a
4’-0” x 4’-0” square piece of sheet steel,
3/8” to ½” thick, should be considered
ot be laid horizontally on a 4” thick layer
of soil or Bentonite over the rock layer.
A bolt or short piece of steel rod welded
to the plate will provide a means of
connection to the steel plate. The plate
should be covered to finish grade with
good top soil.
IMPROVING EARTH GROUNDS:
When a grounding grid is first installed
you are unable to get a true OHMs
reading, since the rod surface will not
be in good contact with the soil. The
grid must be installed for 5 or 6 weeks
before a meaningful reading can be
obtained. It is also recommended that
the grounds be checked at least once a
year and in severe lightning areas
perhaps as often as two or three times a
year.
NOTE ! A good reading CANNOT be
obtained with a volt/ohm meter. A
Meggar or Vigra-Ground type
instrument must be used to check the
ground resistance.
If unsatisfactory readings are obtained,
the ground may be improved in one of
the following ways:
(1) Extend a #6 or larger bare copper
braided wire from one of the rods out
across a fairway and buried a
minimum of 12” below the surface.
Be sure the wire is between rows of
sprinklers and away from other
wires, pipes, etc. as far as possible.
This will place the wire in an area
that will be frequently watered and
will increase the surface contact of
the grounding network.
(2) In the center of the triangle, of the
3-rod grid, install an 8’-0” long
piece of 6” diameter perforated
plastic pipe. Top shall be at least 6”
below the finish grade. Fill this pipe
with rock salt, Epson salts, or other
suitable similar material and water it
down. The salt will leach out into
the soil and corrode the surface of
the rods giving improved and greater
surface contact. Place a 6” diameter