Campbell Scientific Sentek EnviroSCAN Access Tube Installation Guide - Manual (Page 16)

Installing EnviroSCAN, EnviroSM ART & Diviner 2000 access tubes
© Sent ek Pt y Lt d Page 13
Installing access tubes for Diviner 2000, EnviroSCAN and
EnviroSMART probes
Introduction
It is necessary to install Sentek access tubes before Sentek sensors can be used to measure volumetric soil
water content. Access tubes are installed at selected sites using Sentek installation tools. The tools are
specific to the installation method so it is important to understand the installation method before purchasing
your installation tools. A slurry installation method may be used for soil with a high gravel and stone content.
Note:
Inspect the soil types on your property prior to undertaking an installation to
ensure that you have the correct tools. The standard installation kit is designed for
installation in most soil types, but in some situations such as very heavy clay or
rocky soils, additional tools may be required.
Once you have identified your soil properties, read the relevant section of this
manual to determine what tools you require.
If you are unsure about any aspect of the installation method, contact your Sentek
reseller and discuss the sites you have selected and your installation needs.
The aim of the installation process is to cause minimum disturbance to the surrounding crops and soil profile.
Disturbances to the soil may introduce pockets of air and loosely packed soil material. The disturbances
affect the contact of the outer surface of the access tube with the surrounding soil profile and may lead to
preferential flow of irrigation water or rain to a greater depth compared with the rest of the field. If readings
are taken under disturbed soil conditions they may by incorrect or misleading.
Warning:
Access tubes must be installed so that they fit tightly in the soil along their entire
length. Permanent errors can be introduced into the readings through poor or
hasty installations. Any air gaps between the length of the access tube and the soil
will cause data deviations.
For example, the penetration depth of an irrigation appears to be much deeper if
there is an air gap next to the access tube. This misrepresents the depth of the
irrigation in the field at that site.
The addition time taken in careful installation ensures access to accurate and
meaningful data.