24
Rod Length
Water
8 inches (20 cm)
60
-
65%
4.8 inches (12 cm)
70
-
75%
3 inches (7.5 cm)
75
-
80%
1.5 inches (3.8 cm)
65
-
70%
Note: The meter does not read 100% in water because the soil moisture
calibration equations were created to be most accurate in the volumetric
water contents typically found in mineral soils.
Appendix 2
Troubleshooting
Sensor Function Verification:
Test readings can be taken in three standard environments; air, distilled
water, and sand saturated with distilled water. It is important that any
troubleshooting be done with distilled water. Readings taken in tap water
can differ greatly from the expected results observed in distilled water.
Test readings are made in a container of distilled water or saturated sand.
The container should have a diameter of at least 3 inches (7.5cm) and
should be tall enough so the rods can be completely immersed or inserted.
Readings should be taken with the
Soil Type
to Standard
and the correct
Rod Length
selected. The meter should read VWC=0% in air. In saturat-
ed sand, it should read between 35% and 45%. The table below shows the
approximate ranges of volumetric water content that are expected for the
different rod lengths in distilled water.
Unable to save data or load firmware from USB flash drive:
Confirm the drive is not full. Verify the drive has FAT or FAT32
format. Firmware should be in the root directory.
"No Sensor" appears on the display:
Confirm that the probe block is securely plugged into the display.
