The Stator cores of rotating machines are composed of multiple stacked layers to minimize eddy current losses. A short between two or more layers lead to higher local eddy currents. This again can lead to local hot spots which in a worst-case scenario, can cause a partial core melt and eventually the complete damage of the machine. A ring flux measurement, where the machine is excited at rated flux and the detection of the potential hot spots is performed with a thermographic camera, demands a high amount of power. Furthermore, the setup is both time- and resource-consuming.
The stray flux measurement with the CPC 100 is a reliable alternative, using a portable power source and measurement device that can be energized via an ordinary power plug. Beside the measurement at rated frequency, the CPC 100 allows you to excite the stator core at higher frequencies up to 400 Hz. The effect of
the injection at different frequencies, detection of faults “deeper” in the core as well as the comparison to a ring flux measurement is explained in this paper.