A differential pressure gauge / switch / transmitter can help identify pump issues.  Issues such as too high or low suction or discharge pressures  can be caused by  cavitation, loss of flow, mechanical failure, vibration, and bearing wear. While a switch can provide a warning for a defined pressure point, a 4-20ma transmitter in combination with a computer prediction algorithm can be used to identify an impending problem.

A Diaphragm or Piston type differential pressure instrument can be used to monitor pump performance. The selection of a piston or diaphragm instrument will be dependent upon the process and particulates present in the process.  Please read our Piston vs Diaphragm Article.