The high-precision multi-parameter probes of the 36XiW-CTD series measure conductivity and temperature as well as pressure, along with the depth of bodies of water. Temperature dependence and nonlinearity are precisely compensated for in the microcontroller by means of a mathematical model. The integrated Pt1000 achieves an accuracy of ±0,1 °C, and the conductivity can be measured at ± 2,5% of the selected range (0,2 / 2 / 20 / 200 mS/cm). The sensors can be supplied with either an RS485 or SDI-12 interface. Extended lightning protection comes as standard with the SDI-12 and is available as an option for the RS485 interface.