A vibration sensor (or accelerometer) measures vibration-simple, right? But how and where you mount the sensor is CRITICAL to getting good information. Here are some good tips to keep in mind.
1. 
Mount the sensor as close to the bearing location as you can safely do it. These sensors can measure vibration anywhere on the machine. But the closer you get it to the bearing, the better the sensor can measure any vibration generated by the bearing components, gears, etc.
2. If you are not sure of the exact bearing location, some good clues are grease fittings, lube lines, sight glasses, etc.
3. Make sure the sensor is mounted solidly to the surface. When using a magnetically-mounted sensor, be sure the sensor doesn’t rock back and forth.
4. Mount the sensor in the same place, as closely as you can, each time. A good way to do this is to make the location with a permanent marker. A photo of the sensor located on the bearing is even better.
5. Even though modern sensors are quite durable, mount the sensor as gently as if you were placing an egg onto the surface. If you slam it on, the sensor will measure a large vibration, and it will take a few seconds for that signal to settle down. A good way to prevent this is to place the sensor onto the surface at a slight angle, and gently “roll” it into place.
6. If you are using a tri-axial sensor, be sure to orient the sensor in the same position as the previous time.
These are some practices we at VibrAlign use. We’d love to hear your thoughts as well.
