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Stepper motor is extremely jittery in the direction of the limit switch

Hello everyone,

This is my first time using a TIC stepper motor driver so please tell me if I’m doing something wrong.

The setup I have is this stepper motor:

With a TIC 36v4 stepper motor driver. I have connected a limit switch to the SDA input to make sure my stepper motor does not damage anything. The limit switch works as I can the limit switch message in the ticgui if I manually press it. But when going driving towards the direction of the limit switch the stepper motor is extremely jittery and it’s reported speed rapidly fluctuates between 0 steps and 1000 steps. Driving the stepper motor towards the other direction works without problems. If I change the limit switch configuration from forward to reverse the direction of the jitter flips as well.

If I configure the TIC as if it has no limit switches connected it also has no problems driving either direction.

Anyone have any clue what this problem could be? I have ordered a new controller just to be safe.


Can you post some pictures of your setup that show how the limit switch is connected along with a copy of your Tic’s settings file? You can save your settings file from the Tic Control Center under the “File” menu with the controller connected.

A video that demonstrates the problem might also be helpful. The forum does not allow users to post very large videos, but it does work well with videos linked from other sites (like YouTube or Vimeo).

Additionally, if you have access to an oscilloscope, I suggest using that to look at what is going on with the signal from your limit switch.

- Patrick

I swapped out the 36v4 with 834 and used a lower voltage psu and with that controller I don’t see the problem. Tommorow a new 36v4 should arrive and I will test with that.

I redid all the cabling. I braided the limit switches cables, braided the motor cables and added a ferrite to the motor cables. Now the issue no longer seems to occur.

I am glad to hear you got it working; thanks for lettings us know!

- Patrick