EDS-70V/EDS-70P Borehole extensometer measures extension that takes place with the time in a bored hole or in several bored holes in a rock mass.

This system is similar to the EDS-63U-D, except that the EDS-70V/EDS-70P head assembly uses vibrating wire displacement sensors (the EDE-VXX in the range – 50, 100 or 150 mm). Multi-core cables are used to transmit electrical output over long distances. The readings can be taken with a portable readout unit/data logger or through a remote automatic data acquisition system. This system is also available for use with mechanical readout devices.