Hello,
I have a 3 wire 24VDC solenoid for air.
The green/gold ground would go to the 0V, 1 would go to the 24V PWR on the grey Power block, and 2 would go to DO0 right?
Any insight would be greatly appreciated as I’m new to UR!
Thank you!
Green must go to earth (not a terminal in the controller, but one of the earth/case screws).
1 to DO0 and 2 to 0V (the other way around should work as well, though). 
Now, the connector has a rating of 4A - what is the current rating of your solenoid? FIY, The UR controller can only supply 2A of current.
.125 Amps.
Wiring it up like you said worked! Thanks efn!