So I've been running my new boards with my NEMA 17 motors for a while today, and I've noticed that the motors have been getting really hot... Then I got to thinking about the voltage going to them... these motors are apparently rated for 5.1V... but am I correct in guessing that the stepper driver board is putting out closer to 9-12V? What voltage are these boards made for? and is there an easy way to bring that voltage down to the range of 3.3-5.1V? lordcat https://reprap.org/forum/read.php?13,5959,5959#msg-5959 Sat, 06 Jun 2026 19:33:16 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?13,5959,6006#msg-6006 https://reprap.org/forum/read.php?13,5959,6006#msg-6006 degroof Controllers Tue, 06 Nov 2007 11:16:53 -0500 https://reprap.org/forum/read.php?13,5959,5962#msg-5962 https://reprap.org/forum/read.php?13,5959,5962#msg-5962 lordcat Controllers Sun, 04 Nov 2007 08:32:28 -0500 https://reprap.org/forum/read.php?13,5959,5961#msg-5961 https://reprap.org/forum/read.php?13,5959,5961#msg-5961
I've read that a good approximation of the correct setting is the percentage of the actual voltage you want your motor to get. A 5 volt motor on a 9ish volt supply would need a setting of around 55%. If you can turn the torque down even further without skipping steps, that's even better -- you'll use less power and generate less heat.

If you don't want to mess with the torque setting, you could put some resistors inline with the motor (one on each winding) to drop the voltage to whatever you want.]]> Anonymous User Controllers Sun, 04 Nov 2007 01:43:09 -0500 https://reprap.org/forum/read.php?13,5959,5960#msg-5960 https://reprap.org/forum/read.php?13,5959,5960#msg-5960 1. cut the trace between the +12V line and the L298N
2. solder an alternate +5V supply where marked
3. use the - supply as a common ground
That should send 5V to the stepper motor without affecting the rest of the board.

[attachment 319 stepperboard.jpg]

Another possibility is to drive the whole board off of 5V. To do that, you'd remove U1, jumper the +12V bus to the +5V bus and hook up a regulated 5V supply to the power terminals. P4, P6 and P7 won't work but you probably don't need them.

Again, just a wild guess based on a cursory look at the board.]]> degroof Controllers Sat, 03 Nov 2007 21:12:34 -0400 https://reprap.org/forum/read.php?13,5959,5959#msg-5959 https://reprap.org/forum/read.php?13,5959,5959#msg-5959
Then I got to thinking about the voltage going to them... these motors are apparently rated for 5.1V... but am I correct in guessing that the stepper driver board is putting out closer to 9-12V?

What voltage are these boards made for? and is there an easy way to bring that voltage down to the range of 3.3-5.1V?

lordcat]]> lordcat Controllers Sat, 03 Nov 2007 20:23:18 -0400