Data Logger with Conductivity Measurement — DCX-22 CTD

Description

The CTD version of the DCX-22 series is a standalone, battery-powered data logger made of stainless steel. Requiring minimal maintenance, the device can record water level (pressure), temperature, and conductivity over extended periods of time.

Increasingly, conductivity measurements are taken alongside level measurements, where changes in water quality and level need to be recorded simultaneously. Thus, when measuring groundwater levels, contamination caused by saltwater intrusion, dissolved particles, or various pollutants can be detected.

To select the conductivity range (0...0.2 mS/cm, 0...2 mS/cm, 0...20 mS/cm, and 0...200 mS/cm) and set the temperature coefficient of the medium, the Logger 5 software is used. This allows obtaining compensated measured conductivity values standardized at 25°C.

DCX-22 AA CTD

The DCX-22 AA CTD data logger records groundwater levels using the AA (absolute - absolute) measurement method, whereby atmospheric pressure fluctuations are measured and compensated by a sealed atmospheric pressure sensor with a stainless steel diaphragm. The advantage of this measurement method is the absence of the need for a moisture-sensitive capillary tube. Additionally, there is no need to remove the DCX-22 AA CTD from the measuring tube to retrieve data.

DCX-22 CTD

In the DCX-22 CTD, the sensor, electronics, and battery are housed within a single unit. The data logger must be removed from the measuring tube to retrieve data. The DCX-22 uses an absolute pressure sensor. In shallow water, where atmospheric pressure fluctuations must be considered, a second DCX-22 acting as a barometer is placed on the surface to record atmospheric pressure changes. The difference in pressure or water level is then calculated on a computer by subtracting one value from the other.

DCX-22 (SG/VG) CTD

The DCX-22 CTD (SG/VG) version features a connector for the cable, eliminating the need to remove the device from the measuring tube to read data. A locking disc is used to secure the output connector at the surface. In the VG version (compensated pressure measurement), a cable with a capillary tube for pressure equalization is connected to the upper data reading device, and the capillary tube outlet is protected by a Gore-Tex^® diaphragm located there.