The Bently Nevada 3500/46M Hydro Monitor is a four-channel device that accepts inputs from proximity probes, seismic transducers, and air gap sensors. It conditions these signals to deliver both vibration and position measurements, then compares the processed values with user-configurable alarm setpoints. The Hydro Radial Vibration channels combine shaft gap movement with the 1X (NX) amplitude to generate a parameter used for detecting and alarming on shear-pin failure.