Replacing mechanical potentiometer with digital potentiometer for myRIO

[tommyflynn]

Hi,

I wish to replace a mechanical potentiometer on a motor control board which is used to control the speed of a motor with a digital potentiometer. This will allow me to control the speed of the motor using LabVIEW on a PC. I have a myRIO 1900 series.

I am looking for some help with the wiring involved in the removal of the existing pot and replacing it with the digital pot.

I have attached a picture of the motor control board pointing to the pot as well as a pdf detailing the digital pot.

Thanks in advance.

 

[Beau Schwabe]

The problem with using a digital pot is that the resistor terminals can only fall between GND and the supply voltage which for the Digital pot that you provided is 5V maximum.

Any motor controller worth their weight would provide an analog input 0-10V , 0-20mA, etc ... Do you have a datasheet on the motor controller? It's possible that the digital pot could be interfaced another way

BTW) That digital pot uses a AD5160 ... page 3 of the data sheet "Resistor Terminals" indicates GND to VDD for terminals A, B, and W of the digital potentiometer.

https://www.analog.com/media/en/technical-documentation/data-sheets/AD5160.pdf