The Model 4730 Tensioned Wire Extensometer is similar in construction to a wire extensometer Model 4015 except that the wires are kept in constant tension. It consists of corrugated collapsible-tubing connecting spring-actuated anchors, which mechanically anchor to the soil profile. The assembly is prefabricated and delivered ready for installation.
The Model 4015 head frame (with spring loaded sensors) is connected to the anchors by stainless high tensile wire and records settlement between the anchors. The Model 4730 is a good alternative to hydraulic and pneumatic settlement cells, and can be remotely read using data logging systems or Model 9600-2 hand-held readout unit. Range up to 3m. Resolution 0.1mm.