cemf

[jaybee]

Hi everyone ,
I dont fully understand counter electromagnetic force , can u guys explain its concept and how it works.Thanks in advance for any replies.

[drivewizard]

When you appply voltage to a motor you cause current to flow in the windings. This current flow create a magnetic field which then causes an induced current flow in the Rotor. This rotor current also has a magnetic field that opposes the one created in the windings. They are out of phase. This is what allows a motor to run properly without over-amping. That CEMF is not fully created yet till motor gets up to speed so that is why you see LRA at instant of start-up.

There is actually a very large amount of current flowing in Rotors, and a lot of heat generated.
Hope that helps, wasn't very technical. You can go to the textbooks for the technical stuff.

[Edited by drivewizard on 04-17-2005 at 01:20 PM]