Analysis of selected motor event and starting reports

Motors are estimated to be one of the most numerous components of the electric power system. As the device that takes electrical energy and converts it to the mechanical energy needed to power processes, a motor that is unnecessarily out of service can bring an entire process to a halt, resulting in a significant loss of revenue. Conversely, the expense and time to replace a large motor damaged beyond repair mean that failing to quickly and dependably protect a motor is also a concern. Because there are many common failure modes (mechanical, electrical, thermal, and so on), root-cause analysis of a motor failure can be involved. This paper investigates several real-world events with data from both motor starting reports and event records. The data demonstrate the value of having devices capable of recording motor data during starts and fault events and of capturing and reviewing such data for the purpose of determining root cause. Lessons learned are shared to help in troubleshooting motor problems and to avoid potential misoperations in motor protection.