What do you guys think could have caused this cap on my driver to go pop randomly. I have spare drivers on order but seems odd this would just go bad randomly.
Did you check your grub screws? 
6 Likes
Or did you use steel reinforced belts? 
1 Like
Well, that’s the cap that filters VMOT.
Something cycling the power on that really fast would generate some heat, and there’s not much material there to sink it. Or something bringing up the voltage on the ground plane.
Mostly, I’d suspect some sort of load dump overvolting the cap and letting the magic smoke out to play. Could be a symptom of the DRV8825 chip failing, or maybe what looks like a solder bridge in the lower right hand side of the chip?
1 Like
My suspicion is just a cheap part. Drv8825s are as cheap as they can make them. On the plus side, a replacement won’t break the bank.
1 Like
Says the hay dealer to the camel dealer…
1 Like
Looks to be the 4.7uF tank capacitor. Failures like that are from over-voltage (or reverse voltage). Its probably a low quality part that couldn’t handle the inductive spikes on the power lines.
It should be able to run without it, although you probably couldn’t run the motor at higher speeds.
I would have to remove it for that to work. Right now if I put power to that it throws a spark and the PS trips.
Is that something conductive?
Most likely, I’d guess the driver chip itself is toast, and blowing the cap is an effect, not the cause.
1 Like
Didn’t see that. Maybe, I would agree that the cap blowing is an effect rather than a cause. I’m just hoping it’s a bad driver and not a bad mainboard. We will see. Got my new driver’s today and installed one. Maybe I’ll give it some work tomorrow. 