Campbell EasyAG SDI-12, Instruction Manual

B-1 

Appendix B.  Tube Installation 

B.1 Introduction 

B.1.1 Soil 

Suitability 

EasyAG

TM

 may be installed into a range of soil types ranging in texture from 

light sand to heavy clay.  It is unsuitable for installation into stony ground 
where the average stone size is greater than 10 mm.  Larger stones may damage 
the plastic cutting tip of the probe and divert the direction of the insertion. 

EasyAG

TM

 is also not suited to insertion into dry ground, as this causes 

significant back pressure when using the sledgehammer and leads to damage at 
the top of the access tube.  The potential insertion site should be moistened to a 
depth of 1 meter before installation. 

In hard soils, it is possible to cause minor damage to the top of the access tube 
in the top cap.  If this occurs, simply remove the burred edges with a sharp 
knife or file when fully inserted, so that the electronic circuitry may be 
installed.  Care must be taken in any subsequent re-installations, as the 
available surface area for contact of the EasyAG

TM

 dolly will be reduced.  

EasyAG

TM

 is ideal for well tilthed cultivated soils such as commonly found in 

vegetable production areas. 

B.1.2 Sledgehammer Technique 

Blows from the sledgehammer should be well directed straight down onto the 
beating head of the soil auger with as little lateral (sideways) impact as is 
possible.  This minimizes the formation of an air gap between the soil and the 
access tube.  Any air gap here will result in preferential path flow of water 
down the access tube and into deeper soil layers. 

B.1.3  Soil Sampler Extraction 

When extracting the soil sampler, care must be taken so that the integrity of the 
hole is not compromised.  The soil sampler must be pulled directly and 
smoothly upward. 

At no stage should the soil sampler be reinserted, as this will damage the hole 
integrity.  It is better to simply start again if the installation is not progressing 
well. 

B.1.4  Air Gap Correction 

At every stage, the formation of an air gap between the soil and the access tube 
must be limited.  If this is unavoidable, then there are some corrective 
measures that may be taken. 

Small air gaps of 1 

–

 2 mm between the soil and the access tube near the 

surface may be closed with light finger pressure without causing major errors 
in the soil moisture detection. 

A significant air gap of greater than 2 mm between the soil and the access tube 
near the surface may be corrected by carefully pushing a spade into the soil