Controlling a dc motor with VHN5019

Hi, I have a Pololu VNH5019 motor driver which I am using to try and control a dc motor (50:1 Metal Gearmotor 37Dx54L). I am using Labview connected to a NI CompactRio to send a pwm signal to the pwm pin and high and low respectively to the INA and INB pins. I am unable to see any motion in the motor. Can you help me figure this out?


The signals you describe should move a connected motor. Can you post pictures that show how you have made your connections to the board including any soldered connections you made? How are you powering the system? Have you verified that your program is sending the I/O signals that you expect it to be sending with something like an oscilloscope? Do you have a ground connection between your logic device and the motor driver? Also, what is the output voltage of your logic device? Are you supplying logic power to VDD?


Hi Nathan

It does work. It was my bad for not getting the wiring right. Can you guide me to a good resource for position control of the same motor? Thanks.

If you are using one of our motors that has an encoder, the Incremental rotary encoder section of the Rotary encoder Wikipedia page has a good general overview of how quadrature encoders like the ones on our motors work. We do not know of any specific resources for how to perform position control with them using LabView.


HI Nathan

I am having the same problem again. I checked my wiring but it’s no use. Could you tell me a way I could know for sure that the driver is working so I can troubleshoot elsewhere?

I suggest trying to connect the PWM, INA and INB pins directly to GND or your logic supply to see if the outputs behave as expected.