Condition based maintenance through electrical signature analysis : a case study

In modern industrial applications, because of the increasing requirements in term of quality and efficiency, the employment of an effective maintenance strategy is becoming crucial. As a consequence, the service activity is moving towards the development of diagnostics and prognostics techniques aiming to minimize the impact of the failures on the production. In previous papers two simple diagnostic indexes has been presented. It has been shown that under some hypothesis they are effective to detect rotor faults of inverter-fed asynchronous machines. In this work, the effect on indexes due to the accuracy of the current measurement chain has been investigated. This has led to the development of a low-cost diagnostic device employing. Hall-effect current transducers and a dsPIC microcontroller. Finally, it will be shown that the indexes computed by means of this economical hardware are close to that obtained employing a PC interfaced with a much more accurate current acquisition system.