copy program from running machines

hi, just started to learn plc. I've been troubleshooting external plc but not the programming. My question is, can I copy program in a running machine and download it to my PC for personal file? What about software requirements since I am planning to get one now like slc 500 which is the one machine we are currently running. Kindly give me feedbacks on safe hook-ups and/or set-up so as not to disrupt the operations while the machine is running for production.
Ancipates your answers. Thank very much.

I'd start with the back-up copy of the program - this normally include comments etc whereas uploading from the plc may or may not depending on the plc.

You can, but the AB Micro and SLC series PLCs do not download the tag names or tag descriptions to the controller. If you upload without having a copy of the program on your PC, all you'll get are the numbers describing the I/O, bits, and words. No comments either. For most machines, this will be unmanagable.

You need to find the last off-line copy of the logic and review that, instead. Ask around- it's somewhere in the plant, even if it's on some almost forgotten laptop in a corner somewhere. Good luck!

Paul T

Greeting TOTZ ...

and welcome to the forum ...

My question is, can I copy program in a running machine and download it to my PC for personal file?

Click to expand...

this is a situation where you should be VERY careful with the words that you use - and ESPECIALLY with the menu selections that you click on ...

with Allen-Bradley systems, the word "DOWNload" that you used means that the program moves "FROM" the computer "TO" the PLC ... according to what you've posted, that's NOT what you want to do in this case ...

and with Allen-Bradley systems, the word "UPload" means that the program moves "FROM" the PLC "TO" the computer ... according to what you've posted, that sounds a lot more like what you had in mind ...

sad story time: I used to work for an Allen-Bradley distributor (no, that's not the sad part) ... two or three times a year, the phone would ring and a very disturbed programmer would ask (too late) for a definition of the words "download" and "upload" ... seems that he had just "UPloaded" when he should have "DOWNloaded" instead ... (now it's getting sadder - but we ain't through yet) ... when I asked if he had a backup copy of the program, the answer was often, "No, the only backup was on the laptop I just uploaded to - and then the next thing that I did was saved the file." ... (and now it's time for the crying towels) ...

and pay attention to the advice about "comments, etc." from Simon and Paul ... you're usually a LOT better off with an up-to-date copy of the program from a backup file - for the "documentation" reasons that they mentioned ...