The Most Important Part of an Electric Motor

There is no 'most important' part of a system, and an electric motor is a system that all components must be correct in order for it to operate properly...now if you were to say what part fails the most often, I would say the winding insulation in larger motors and bearing lubrication in smaller motors....but I suspect that is subject to environmental conditions and can vary based on several factors, including power quality and location...

The most important part is the mechanical load for the motor. Without this task, the motor won't exist.

Many moons ago, I was taught by an electrical engineer that the most important part of the motor is the data plate. It can be replaced exactly if non repairable, and any parts needed can be sourced.

It has been proven valid over my many(50+)years of experience.

The shaft, for without one the motor is shafted.

Very Good,2 dogs.

If you put tennis shoes on a bear, will he still have bear feet?

(Works better spoken than written).

SMOKE!

Correct. If the factory smoke escapes from a motor it can never be put back in. It is a free dark(herein referred to as an Unphoton) sucker and quickly dissipates .It is capable of moving in geosynchronous orbit with the Earth, and also can be found in many other places.

Dark suckers are becoming extinct in some places due to artificial lighting, however defeating dark suckers is not cheap, it require power to do it.

Bugs love dark suckers, so they circle around the lights and collect all they can during the blanking interval.

Ah yes, the magic smoke...how many times have I seen it escape the confines of the insulation and run rampant in the enclosure, surely to be accompanied by a large plasma discharge which typically results in some sort of random, vigorous combination of oxygen and whatever material happens to be in the area...

The joys of commissioning!!!

The electricity.