Just for reference, I'll post thumbnail schematic from "Chemlee" first. This is the one I built first, operated at 12v, and blew the diodes & mosfets.
And this is my interpretation:
Anyway, I have this operating a 12v, 10 amp grinder. I operated it at 7A to 8A for about an hour, and it held together, mosfets are cold,
freewheel diode warm. Any observations are welcome. I am new to PWM.
In my reading, the freewheel diode, EMI diode, avalanche diode, snubber diode, or whatever it's called,
is essential when switching inductive loads. I have ONE freewheel diode on the motor leads, not the 3 located on the mosfets
as in the first schematic.
My freewheel diode isn't "SOFT RECOVERY", just a fast diode I had in my junk. If anyone can recommend a good, cheap, popular
freewheel soft recovery diode that I can find on ebay, let me know. I want something that will work from 12volts thru 150volt motors. Would a 200v rating be sufficient?
Okay, all for now.
And this is my interpretation:
Anyway, I have this operating a 12v, 10 amp grinder. I operated it at 7A to 8A for about an hour, and it held together, mosfets are cold,
freewheel diode warm. Any observations are welcome. I am new to PWM.
In my reading, the freewheel diode, EMI diode, avalanche diode, snubber diode, or whatever it's called,
is essential when switching inductive loads. I have ONE freewheel diode on the motor leads, not the 3 located on the mosfets
as in the first schematic.
My freewheel diode isn't "SOFT RECOVERY", just a fast diode I had in my junk. If anyone can recommend a good, cheap, popular
freewheel soft recovery diode that I can find on ebay, let me know. I want something that will work from 12volts thru 150volt motors. Would a 200v rating be sufficient?
Okay, all for now.
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