Seems some rocket scientist bumped this old thread at OU.com,so i had a read through it.
I found a post made by Poynt99 in this thread relating to BEMF and inductive kickback.
Hope you dont mind me posting your explanation here Poynt?
Quote: Perhaps a simple way to distinguish between bemf and inductive kickback (IK) is to ask yourself, "does the effect take place simultaneously, or in sequence?"
bemf is a simultaneous phenomenon, whereas the IK effect takes place in a certain sequence of events. In a motor, the instant you apply power there is very little if any bemf generated, so the input current is high, but once the motor is running at speed, the applied emf, and bemf are in opposition simultaneously. When you are switching inductors, there is a definite sequence of events; i.e. you energize a coil, then remove the applied emf, then the coil tries to continue the current flow and as such reverses its output voltage, most often in a short high voltage spike. But that is determined by the load seen by the IK spike. THAT is IK.
So generally speaking, if you are switching/pulsing inductors, you are generating/collecting IK. If you are powering motors, the bemf effect is taking place, limiting the current into the motor. Without bemf, motors would draw huge amounts of current all the time.
Hope that clears things up a bit.
So it seems that Poynt99 agree's with me,or to be more correct,i agree with Poynt.
Brad
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Never let your schooling get in the way of your education.
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