The geophysical roller (block-balance) is designed to guide and measure the length of the geophysical cable, which is lowered into the well.
Block-balance (geophysical roller) is included in the set of the logging station hoist. It can be equipped with sensors of depth and speed, magnetic marks ("Jason" system). It consists of a suspension (or stand) and a roller along which the geophysical cable runs. Main advantages: lightweight.