Motor & diode.
Okay, with this I'm struggling yo understand the current flow of this Back-Emf and this diode.
As far as I get it;
When the motor is off, (obviously there's back emf i know that) basically it says it let's current flow from the motors negative to the positive. How im not sure. Because ro me hsi diode seems the wrong wsy around for that.
(Its some guy of youtubes video I screeenshoted.)
Thanks.
2 Replies
the diode does nothing when current flows through the motor (it's reversed biased).
when the motor stops its magnetic field collapses and that induces a large current in the opposite direction (the back-EMF). Since the polarity is opposite current does now flow through the diode. If the diode wasn't there that large reverse voltage spike could potentially exceed the specs of the transistor or MOSFET that drives the motor.
Helpfull for me thx.