Connected Components Workbench's Micro800 Simulator is a good way to decide if you want to learn PLCs.

Note I did not say that you can make it through this course with the simulator.  If fact I will tell you that you cannot make it through this course with the simulator.  

But if you have contacted me about purchasing a PLC Trainer and were on the fence about committing to this journey, I likely told you to sign up for this course and proceed through the counter lesson with the simulator then contact me and let's discuss career options.