Specific Notes - Delta-T Devices SWT5 User Manual

1.6.5 Specific notes


SWT5 and SWT5x are not suitable for dry soils and they are not
frost resistant.

When installed in the field provide sufficient protection.

The less air that is inside the cup, and the better the soil's
conductivity is, the faster the Tensiometer will respond to tension
changes.

It does not make sense to refill a Tensiometer while the soil is dryer
than -90 kPa (-900 hPa) for the SWT5 or - 160 kPa ( -1600 hPa)
for the SWT5x.

The use of a quartz clay slurry is only recommended in clayey soils
and only if the drilled diameter is larger than the shaft diameter (5
mm). In coarse sand or gravel soil a fine grained slurry paste would
act as a water reservoir which would lead to a slower response.

The SWT5 can be installed in any position and orientation. Bubbles
are easily detectable through the transparent shaft.

Output signals are standardized.
10  Introduction
SWT5 User Manual v2