18v7, Linear Actuator, cRIO

Hey, I was hoping to get just a bit of support on this topic.

Pololu SMC 18v7 fully assy
Linear Actuator (12 v)
National Instruments - NI 9074 cRIO w/ analog Input, analog output, digital I/O available

Pololu SMC Windows 7

What’s working:
I can move the linear actuator using the USB.

Desired Action:
I have setup my lab view with conditional statements so that a temperature range is exceeded, the analog output supplies 1v or 3v, to cause the retraction or extension of the linear actuator. 1v = -100% and 3v = 100%, there is also a condition for acceptable range temperatures to output 2v, which i hope should be 0%. With the supplied voltage, my intent is to use the analog input and cause action using the emulated potentiometer readings. (1 or 3v)

My issue:
Right now, when I go to LEARN - i get an error that says, “Analog 1 (Invalid connection)” or something similar.
-I’m not really sure what the minimum amount of wires I need to connect to the SMC from the cRIO to get this working. I feel like I am most of the way there on my concept, but I am just unfamiliar with the wiring. I have tried putting the analog output on the pot(-) and pot(+) connections, as well as a few other configurations with the two wires. I am wondering If I need to supply a 3v DC to the Analog Input (Yellow in manual) and then commonly ground the connections? Do I need to put the jumper somewhere on the board? What is the correct wiring?

Keep it simple, I don’t know how to do the TTL / serial connection, so I was hoping to use the analog control.

Thanks for your help.


Since you’re not using a potentiometer, the pot disconnect detection feature needs to be turned off. To do this, put a check mark in the “Ignore pot disconnect” checkbox in the Advanced Settings tab.

Then you only need to have two connections from your control device to the Simple Motor Controller to get the analog input to work:

  1. Connect a GND pin of the Simple Motor Controller to a GND/ground/Vss pin of the control device.
  2. Connect the A1 pin of the Simple Motor Controller to the analog output of the control device.