MattMatt9,
ANYTIME you get a plc into your plant, you need to do the following.
1. get with those installing the system and learn all you can about the system.
2. ask about the plc and how it is programmed.
3. GET A COPY OF THE program on disk, cd, jump drive... and open it to verify its there and is the actual program.
4. before the guys leave, have them back up the software (hmi, scada,plc) and save it to your jump drive and verify its there. then go open the program to verify its correct. you may not have the latest version of software.
5. get the machine drawings, electrical, pneumatic, hydraulic prints, and any other prints, manuals, instructions....
6. if they refuse, get with the project manager and let him know what is going on.
now to your question.
before you turn off the power,
1. use your pc and connect to the plc using the software.
2. copy the program to a safe location as insurance
3. open the program, go online, and upload the program to the pc. this program is the master copy, regardless of what your pc files are, this is the working copy and therefore it is the master copy.
4. save it to the pc and compare the files, changes may have been made without anyone knowing it.
5. it is now safe to turn the plc off, you have a program copy.
the reason for this is because even though you have a good battery and know the plc is in good condition, things can happen. this is from personal experience. we have the master copy on hand on all plc's and our backup software does a routine backup of all plc files.
james