How Electric Motors Die

This is a brief demonstration of the way increasing mechanical load causes any electric motor to slow, producing more torque to match that demand. As the motor slows, back EMF is reduced, resulting in a higher voltage drop across the motor and an increase in amperage draw. This is the power the motor needs to maintain a steady state. Unfortunately when the motor is slowed, cooling across the fins of the blower resistor is reduced, and higher amp draw increases waste heat, which will eventually destroys the blower resistor, connectors, or the motor itself. In any motor with signs of increasing current and overheating, you want to do all you can to fix any source of mechanical resistance. If the blower resistor has failed, don't forget to clean the motor intake and housing. #shorts

[@spelunkerd]

One of the counterintuitive things about centrifugal blower motors is the way they typically draw LESS current and spin FASTER when either the output or the input air vents are restricted! This is well documented in the HVAC industry with PSC motors. Evidently a restricted centrifugal blower motor can circulate air within the housing without requiring much torque if there is no pathway for fresh air to enter and exit properly. The motor is doing less real work, there is less incoming mass to accelerate and eject, so torque is lower and speed if faster. For more info, search "Understanding Centrifugal Fan Motor Performance". This motor was humming and running more slowly because of mechanical strain caused by a little stack of pine needles wedged between the wall of the housing and the squirrel cage. It's fixed, and working far better, with just a little cleaning.

[@spelunkerd]

This is my first toe in the water regarding the new format of UA-cam shorts. The format demands a vertical aspect ratio which I don't like, but the requirement to be less than 60 seconds is interesting. I always appreciate an author who makes the effort to compress what he wants to say as efficiently as possible. The challenge of a diverse audience is not as easy as I thought it would be, there is no time for deep explanation. What do you think about UA-cam shorts for auto repair?

[@BaptistJoshua]

For some fixes this works. Probably most need longer explanations.

[@memberarnshine6377]

Absolutely great video, we need more people like you, keep up the good works

[@condor5635]

Great video love the Fluke pair. Got the same ones!

[@SVImpavidus]

Short and sweet! Sail Safe mate.

[@memberarnshine6377]

In fact I just subscribed to your channel