from Mt Sopris

The QL40FTC and QL40FTC-B Fluid Temperature Conductivity probes provide high quality borehole temperature and fluid conductivity measurements. Each sub can be run stand-alone, or with other QL tools in a custom stack. The FTC-B is a bottom sub, while the FTC is an inline sub.

QL40-FTC Schematic. Image courtesy of Mount Sopris Instruments.
QL40-FTC Schematic. Image courtesy of Mount Sopris Instruments.

Measurements can be calibrated in uS/cm or mS/m for Conductivity and degrees F or C for Temperature. Other QL probes commonly stacked with the QL40FTC include the QL40GR (Natural Gamma), QL40RES (Multi-Point Resistivity), and QL40CAL (3-Arm Caliper).

To improve the accuracy of measurements the QL40-FTC sensor is protected within the noise of the probe as a result the nature of the measurement the QL40-FTC probe has to be fitted to the bottom of a stack.

Basic water quality logs have many applications. This tool is frequently used in ground water work, geothermal gradient logging, salt-water intrusion studies, and many more environmental projects.

Product Dimensions

Physical Dimensions (L x W x H) Weight
QL40-FTC (instrument only) 78cm x 4.2cm x 4.2cm 3.35kg

Technical Specifications

Pressure Rating: 200 Bar (3000 PSI).
Operating Temperature: Up to 70ºC.
Sensor: Conductivity: 7 electrode reciprocal Wenner array.
Temperature: Linear response semiconductor sensor.
Range: Temp: -20 to +80ºC
Conductivity: 50 to 30,000 uS/cm
Accuracy: Temp: better than 1% F.S.
Conductivity: Better than 1% F.S
Resolution: Temp: 0.1ºC
Conductivity: 0.05% F.S..5mm


Contents Dimensions (L x W x H) Weight
Fluid temperature and conductivity probe
144cm x 40cm x 27cm 25kg

Data Sheet