Time Domain Reflectometry (TDR) is widely used to measure soil water content, bulk electrical conductivity, and rock mass deformation. TDR measurements are nondestructive and offer excellent accuracy and precision.

Time domain reflectometry systems based around the TDR100 consist of a reflectometer, datalogger, coaxial multiplexer(s), cables, and probes. A TDR100-based system is generally used for longer-term projects. These systems offer significant benefits when large numbers of probes must be monitored continuously.