Interfels Linear Potentiometer Crackmeter is a robust, high resolution and accuracy instrument designed to measure displacements across cracks and joints in buildings, bridges, dams, pipelines etc. It can measure in expansion and contraction.

The rugged, waterproof potentiometer is anchored to the structure to be monitored with grout-in or expansion anchors. A change in distance between the anchors, caused by the crack opening or closing will cause a connecting rod to move within the potentiometer body, changing the potentiometer out put and thus the movement of the crack can be determined.