DRV8825 question(s)

Hi all,
I’m planning to add a powerfeed to my mini mill by using one little NEMA 17 drived by and Arduino and one of you DRV8825 drivers.
The idea is to have a couple of gear and a toothed belt drive connected to the hand weel of the axis, so I can still use the mill in manual mode.

Talking with some guy they told me to always disconnect the motor from the driver as the current generated by the motor turned by hand could destroy the driver itself.

I’m not good at electronic so I prefer to ask to who made this driver.

Is that true ?
Can be avoided in some way, in case it is true ? Eventually adding some more components on the driver side ?

Thanks in advance.


Hello, Pierluigi.

Spinning a motor will generate some voltage on its leads, but it’s generally not something that will destroy your electronics. One exception is if you manually spin the motor faster than it spins when you power it; in that case, the voltage you generate can be higher than what your electronics can handle. You could add a big transient voltage suppressor (basically a big zener diode) across your supply to protect your electronics, but you have to make sure it’s sufficiently past the voltage you normally operate at.


Than you very much.
I will try your suggestion !