Measuring vibrations on your critical assets starts with selecting the correct sensors, determine the correct location along the shaft line and calculate the minimum and maximum frequency to be measured.
Journal bearings
Proximity probes to measure relative vibration/motion of the shaft. (2 probes in a 90° angle from one another, see figure below)
Velomitors in Horizontal and Vertical direction to measure the absolute vibration of the bearing pedestal.
Phase reference signal.
Correct Location
Most of the time the location to place the vibration sensors is at the bearings. ISO 20816-2 is a very good guideline that helps selecting the best location for your critical assets.
Select measuring range
To be sure all of the fault frequencies that can occur while operating your machine are captured, it is important to select the maximum frequency and also the minimum frequency. Rule of thumb is Running frequency x 20
Calibrating your sensors
Make sure that Maintain your vibration sensors by regularly calibrating your sensors. A good moment to do this is for example during a major overhaul.