Today I was messing around with my CNC shield (version 3.00) and GRBL. But somehow I managed to accidentally reverse the polarity of my power cables. Until today I had no problem keeping that in mind. The fuse was blown and like it’s not enough yet- drives also. DRV8825 drives have no reverse polarity protection- I toasted 3 of them in a blink. Capacitors seemed to be fine. I have read that if they get the wrong polarity for a moment it doesn’t ruin them instantly.
I “replaced” fuse by soldering random wire in place of the original. I hope it will act as a fuse as well someday? Everything seemed to work. It uses some kind of glass fuse with no markings on it. So I am not sure with what I should replace it with. Of course, had to replace drives. Arduino seems to be also undamaged by this mishap.
A newer version of these boards does not have this fuse.
Photo of the burned fuse
Here is the photo of the aftermath.
Arduino CNC controller shield with a blown fuse
What to use for replacement fuse?
If someone knows let me know what should be the correct fuse. I tried to find an answer for it but with no luck. Most of the threads I found on the internet suggest it to be replaced with a solid wire instead.
I suppose it must be enough to drive all the motors. If you run 3 motors on 1.5 amperes each- fuse should withstand at least 3 x 1.5A => 4.5 amperes.