Hi Eric,

Please let us know the following information regarding your PLC behaviour and let's check all the steps, but take into account that each digital output can handle a maximum of 300mA, please use an external contactor that handles this amperage peaks between the digital output and the Motor. Also you can use the industrial shields relays of your equipment (maximum of 220VAC-5A)

1) Are you powering the PLC with an external power supply unit? (12 to 24Vdc) 

2) Are you powering the optoisolated digital outputs with an external voltage? ( from 5Vdc to 24Vdc) 

Here you can check how to handle the connections and also a programming and vídeo example: 
https://www.industrialshields.com/es_ES/blog/arduino-industrial-1/post/basics-about-digital-outputs-of-an-industrial-plc-31

Relay example of connections, usage and programming: 
https://www.industrialshields.com/blog/arduino-industrial-1/post/learning-the-basics-about-internal-relays-of-an-industrial-plc-180

More information regarding your PLC model: 
https://www.industrialshields.com/technical-features-industrial-m-duino-plc-arduino-ethernet-38ar-ios-analog-digital-relay-plus

Please let us know if you are following all the specifications and any problem or question that you may have, do not hesitate contacting us, 

Have a nice day :)