Sometimes called “electrical center,” it’s the axial position that the shaft/rotor assembly will attempt to maintain during steady-state running at rated voltage and frequency, without the influence of any coupled load

The magnetic center is found by running the motor uncoupled. The motor rotor will find its natural/magnetic center.

While the motor is running, take a steel rule or scribe and CAREFULLY touch the top of the shaft right at the motor housing (where the shaft comes out).

As a safety feature: Determine which direction the shaft is turning, so you can be standing on the side where the top of the shaft is turning away from you.

This will leave a small scribe mark on the shaft that can be used when aligning.