I have built a Prusa Mendel and have two Nema 17's on the top to run the Z axis. Each motor has 4 wires which I have connected together. Each matching colored wires are connected together, and are then connected to the 4 wires from the Controller. What happens is that the motors do not run in unison as I expected. Sometimes they do, sometimes one motor will run very fast while the other won't run at all. I know very little about electronics so it wouldn't be a big surprise if I have it all wrong. Can someone please suggest how these should be wired? See attached rough drawing of how I have these two motors wired. Thanks for any help you can give. https://reprap.org/forum/read.php?160,116515,116515#msg-116515 Sun, 15 Mar 2026 22:16:38 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?160,116515,116878#msg-116878 https://reprap.org/forum/read.php?160,116515,116878#msg-116878 Parallell wiring would work decently if both motors had the same load.
I solved this by wiring the motors in series. The series wiring is briefly described at the wiki page as an alternative wiring method. Take your time to draw your coils and color-code. Worked well for me.]]> Lanthan Stepper Motors, Servo Motors, DC Motors Thu, 02 Feb 2012 12:07:43 -0500 https://reprap.org/forum/read.php?160,116515,116692#msg-116692 https://reprap.org/forum/read.php?160,116515,116692#msg-116692
If it is not you might have misaligned one of of the rods, which makes one motor failing earlier when increasing speed as it needs more torque to turn.]]> DeuxVis Stepper Motors, Servo Motors, DC Motors Wed, 01 Feb 2012 05:12:55 -0500 https://reprap.org/forum/read.php?160,116515,116643#msg-116643 https://reprap.org/forum/read.php?160,116515,116643#msg-116643
Make sure the axis is not binding. Try moving a bit slower or increasing the current a bit. If you find you want more torque you can wire them in series instead of parallel but the max speed will then be lower,]]> nophead Stepper Motors, Servo Motors, DC Motors Tue, 31 Jan 2012 19:10:49 -0500 https://reprap.org/forum/read.php?160,116515,116636#msg-116636 https://reprap.org/forum/read.php?160,116515,116636#msg-116636 Apexhunter Stepper Motors, Servo Motors, DC Motors Tue, 31 Jan 2012 18:05:10 -0500 https://reprap.org/forum/read.php?160,116515,116518#msg-116518 https://reprap.org/forum/read.php?160,116515,116518#msg-116518
Do you get identical multimeter readings when you test the identical wire pairs from both motors?

I have found it a good idea to solder wire connections and then use block connectors on the soldered joint - just to ensure good contact on all the wires.]]> BillC54 Stepper Motors, Servo Motors, DC Motors Tue, 31 Jan 2012 00:57:51 -0500 https://reprap.org/forum/read.php?160,116515,116515#msg-116515 https://reprap.org/forum/read.php?160,116515,116515#msg-116515
Each motor has 4 wires which I have connected together. Each matching colored wires are connected together, and are then connected to the 4 wires from the Controller. What happens is that the motors do not run in unison as I expected.
Sometimes they do, sometimes one motor will run very fast while the other won't run at all. I know very little about electronics so it wouldn't be a big surprise if I have it all wrong. Can someone please suggest how these should be wired? See attached rough drawing of how I have these two motors wired. Thanks for any help you can give.]]> Apexhunter Stepper Motors, Servo Motors, DC Motors Mon, 30 Jan 2012 23:57:47 -0500