What is the term for the method used to determine whether a motor issue is electrical or mechanical?

The method of shutting off the power and turning the rotor by hand is effective for determining whether a motor issue is electrical or mechanical. When the rotor is turned manually, it can provide insight into the mechanical condition of the motor. If the rotor turns freely without obstruction, it suggests that mechanical issues are not present, which could indicate that the trouble is electrical in nature—such as problems with the motor windings or power supply.

In contrast, if the rotor is difficult to turn or does not turn at all when attempted manually, it indicates a mechanical obstruction or failure, such as bearing issues or rotor binding, which would suggest a mechanical problem rather than an electrical one.

Turning the rotor by hand is a straightforward, low-risk technique that helps technicians quickly assess the basic operational state of the motor. This method can often lead to faster troubleshooting and repair decisions.