Welcome!

Let's check all the steps to let this inputs work: 

1. When you connect the external power supply (12/24Vdc) and without connecting the USB port to the PC, the green power led located on the top zone must be lighting. Then, please connect the PLC to the PC and with the Industrial Shields boards installed select the following Model depending on the version that you choose: 

    2. Now, check the connections and programming with these links:

• Dig. Inputs: https://www.industrialshields.com/blog/arduino-industrial-1/post/basics-about-digital-inputs-of-an-industrial-controller-30

• An. Inputs: https://www.industrialshields.com/blog/arduino-industrial-1/post/learning-the-basics-about-analog-inputs-of-an-industrial-plc-29

• Dig. Outputs: https://www.industrialshields.com/blog/arduino-industrial-1/post/basics-about-digital-outputs-of-an-industrial-plc-31

• An. Outputs: https://www.industrialshields.com/blog/arduino-industrial-1/post/basics-about-analog-outputs-of-an-industrial-plc-28

    3. Take into account that the digital outputs are opto isolated, so that you will need to introduce them an external GND         reference and Voltage (5-24Vdc) 

I hope I have been helpful.