The CTD versions of the DCX-22 range are autonomous battery-operated data collectors made of stainless steel. Requiring little maintenance, they record the water level (pressure), temperature and conductivity over long periods. CTD stands for Conductivity, Temperature and Depth.
This data sheet specifies the additional conductivity measurement function which distinguishes the CTD version from the standard DCX-22 product line. The pressure and temperature specifications are set out in detail in the data sheets for the DCX-22 AA and DCX-22 (SG/VG).
Conductivity is increasingly being monitored in conjunction with depth measurements, in which changes in water quality and depth are required to be detected simultaneously. Thus it is possible to detect contamination caused by salt water infiltration, waterborne particles or general pollutants when measuring groundwater levels.
KELLER’s Logger 5.1 programming and readout software is used to select a conductivity range (0…0.2 mS/cm, 0…2 mS/cm, 0…20 mS/cm or 0…200 mS/cm) and set the temperature coefficient for the medium. This process produces compensated conductivity measured values standardised at 25 °C
DCX-22 AA CTD
The DCX-22 AA CTD data collector records groundwater levels using the AA (absoluteabsolute) measurement method, whereby fluctuations in atmospheric pressure are measured
and compensated for by the watertight atmospheric pressure sensor with its stainless steel diaphragm. The advantage of this measurement method is that no humidity-sensitive capillary tube is required. As well, it is not required that the DCX-22 AA CTD be removed from the immersion tube in order to extract the data.