I am a college student using the IMDRALOGIC XLC L25 model plc and am trying to create a simple single double acting cylinder operation which is A+A-. I am using SFC to programme this and am using 2 limit switches, a bi-stable solenoid valve and the output and input PIOs with a hardwiring pneumatic rig also from rexroth. I am having trouble programming as the error message that appears is C0018 which says unassigned variable or cannot find variable location. I am a college student using plc for the first time and have to figure this out alone. Are there any suggestions or useful guides I can follow so that i can get my system working and so that I can get a general idea how to programme? Below are some photos I’ve taken of the software I’m using and the current programme I have coded.
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