Help, please explain a PLC program to me

[OkiePC]

Well, part of it is supposed to be an "independant study" project for me to do. The instructor just showed me the machine and showed me that program and told me to explain how it operates. I barely just got done taking the intro to PLC in a structured class. I think he is expecting me to do this all on my own and he pretty much gave me no instructions or help on how to do it.

Well, then you need to sit with your references and go through the program line by line until you can read and understand each instruction and what it does. Have a pad and paper next to you and take notes. Translae the code into a list of steps that you understand. Make charts where applicable, to show successive scans of the program. Once you are done, change the state of one of the inputs and do it all over again....

You should show that you have tried and tell us what you understand about the very first ladder logic rung in the program. Showing effort will get better replies here.