Product Manual

6
Installation
A good contact between the buried portion of the IRROMETER and the soil is
essential in order to obtain accurate readings.
If air is permitted to follow down the plastic tube, due to an oversize hole and
reach the ceramic tip, false readings on the “high” side will occur. If free water
falls/follows down the tube, false readings on the “low” side will occur. The
specific suggestions below are offered to prevent either of these conditions.
In very loose soil, the shorter instruments can sometimes be installed by
simply pushing them into the ground, without subjecting them to undue strain.
This results in good contact with the soil and minimum disturbance to the soil
structure and root system.
In most cases, however, it is necessary to prepare a hole before making
installation. While IRROMETERS may be installed at any time, it is usually
easier to prepare the hole when the soil is fairly moist.
The diameter of the IRROMETER tube is 7/8" (22 mm). A pointed 7/8" (22 mm)
steel rod or a standard piece of 1/2" galvanized pipe usually makes the most
convenient installation tool and makes a hole the exact size of the
IRROMETER. This assures good soil contact with minimum disturbance to
roots or soil structure. Drive it into the ground to the exact depth at which the
ceramic tip is to be installed. Avoid drilling the hole too deep as this permits air
and water to collect in the hole below the tip and affects the accuracy of the
readings.
A variety of installation tools are available which make installation easier in
hard or rocky soil and with deep depths. For very coarse or gravelly soils, an
oversized hole (1" – 1.25" [25 mm - 32 mm]) may be needed to prevent
abrasion damage to the sensor membrane. In this case, auger a hole to the
desired depth and make a thick slurry with the soil and some water. Fill the
hole with this slurry and then install the sensor. This will “grout in” the sensor to ensure a snug fit.
After the instruments are installed to the proper depth, the surface of the soil should be banked up around
the plastic tube and packed to a depth of 3 or 4 inches, to ensure good contact between the soil and the
instrument, and provide drainage for surface water away from the IRROMETER.
NOTE: In very light (coarse) soils, the access hole depth can be made
2" less than full depth. Pour some water in the access hole, set the
instrument in hole and bear down on top of
cap (NOT GAUGE) to push tip the last 2"
into the soil. This helps establish a snug fit
between tip and soil.
Handle the instruments carefully when
installing or removing from the ground. Do
not put a strain on the gauge connection by
pushing or pulling on the gauge. Push
straight down on the filler cap when
installing. When removing from the ground,
rotate the instrument first to break it loose
from the soil.
NOTE:
Always rotate
IRROMETERs with threaded tips clockwise
to avoid loosening the tips
. Then grasp the
Drive to exact depth of tip
Poor Installation
Proper Installation
Pushing on cap