Help Programming AB to EZplc

Hello All,
As you can guess by the title I am a total noob to programming PLC's. So my problem is that I have an old Pallet wrapper that uses an Allen Bradley SLC 500 1747-l20A PLC. I have spent 6 months working with the manufacturer of the pallet wrapper but still can not get a proper program loaded on the EPROM chip and loaded to the PLC (it always shows PLC fault)

At this point I have purchased 3 more PLC's and a new CPU chip... it has to be a software issue since I can use a EPROM chip off a different machine and the PLC does not show CPU fault.

I reached out to Allen Bradley and found that this PLC is very old and a legacy non supported piece of hardware. Between cables and software I am looking at over a grand to make this work.

I am looking at EZ-Automations PLC and their EZ-PLC editor software, it seems much more straightforward.

SO the problem is that I have the ladder logic and .RSS file from the old PLC but need to convert it to work with EZ plc. Remember line one of this thread... I am not familiar with ladder logic.

I am curious if anyone out there is willing to help me out (willing to pay a little) and convert the ladder logic over to EZ-PLC. I don't want to have to learn the old RS Logix system and the EZ PLC just to convert it. I do have the file, a PDF of the ladder logic and a wiring diagram of the machine.

I know this is a long shot, so thanks in advance.

P.S. as I mentioned I do have 3 nice plc's if you want one... maybe trade for services??? plus cash???

Welcome to the PLCTalk forum community !

The 1747-L20C has 12x 24 V DC sinking inputs, a High-Speed Counter input, and 8 relay outputs. To migrate this project, the first thing I would look at is the *.RSS file to see if the high speed counter is used, and how.

Ideally, ZIP and post (or if you don't want to do that publicly, send it as a private message) the *.RSS file.

I don't care for EZ-PLC's physical robustness, and you're going to find more system integrators who can maintain an A-B controller in the future. A MicroLogix 1100 with a couple of expansion modules would be my default choice, mostly because the ordinary PLC instructions would be identical to the older SLC-500.

Thank you for the fast reply. I have seen other people not as confident with EZ automation products. My use is super basic there are just switches even the optical sensor appears to just act as a switch... So maybe it will be good enough?

I am open to other options but my goal is to find something I can learn on and hopefully develop other machines using that chosen PLC. EZ seemed, well simple.

I Just performed a quick search on the MicroLogix 1100 and it appears to be active mature in the lifecycle. I am afraid it will be obsolete in the next 5 years, so I will have to do this again :-(


Here are the files, thanks for the .zip tip.

If you use an AB micro 820 plc, it looks like there’s a pretty simple way to convert the program to ccw. And ccw is free.

At first I though *snort*, then I thought hmmm, I wonder what the author intended to happen here. d'Oh, the second one is a TOF!

Anyway, I have some queries (to OP and/or anyone) and comments/suggestions:

• What is the timeframe?
• Does CCW have /TT? Maybe with function block wrappers around TON and TOF?
• There are some duplicate OTEs; does it make a difference that they are in different routines?
• Is there an HMI involved?
• Micro8xx will have a longer life than MicroLogix 1100, but the latter might yield an easier/faster port to make the client happier sooner, then there is some breathing room to port to something more modern, so that may be a better overall path, although more involved.
• Does anyone think this can be realistically bid for under a grand or two? Not at my rates. Sure, the first pass at the port can be done fairly quickly, but verifying it is right, helping with new installation, etc., and all the other overhead is what is going to add up.
• How about pro bono for Phil and PLCtalk?

Does Micro8xx have TND instruction (LAD 2, Rung 0021)?


Also, can anyone see where N7:2 is assigned a value other than 0?


OP: did this program ever work?


Also, from the drawing, there is a physical operator interface panel, and no digital/touchscreen HMI, is that correct?

The pallet wrapper worked perfectly for years, when I relocated it sat without power too long. The program fell out of memory. I had this issue years ago and was able to have the manufacturer send the program and it worked. That time it was performed by a guy who had been there for decades... The recent software is from someone who has been there months.

So I am not sure if this program works fully, because it is what causes the SLC 500 to go into CPU fault mode. What I understand from the ladder logic makes sense for the required operations, so at least I know this is pretty close to what would be required for this type of machine.

This is a really simple machine, so no digital HMI. It has three red lion counter displays to show the number of turns set for the bottom and top of the pallet and a total counter. Otherwise it is switches and buttons.

I need to figure this out before September so I can trouble shoot in September/ early October. It needs to work pretty well into November.

Do you think the PDF attachment is the same as the .RSS file in the .ZIP attachment?

It should be, I couldn't open the RSS

I was able to convert it to micrologix 1100, there were only a half dozen OSRs in SLC that needed to be ONSs, and it downloaded without any problem to my 1100 using freebie RSLogix Micro Starter Lite.

The CCW conversion tool conversion from there to Micro820 threw some errors, but it might be rectified with some effort. Uh

RET said:

If you use an AB micro 820 plc, it looks like there’s a pretty simple way to convert the program to ccw. And ccw is free.

Click to expand...

Interesting, that could work. I just want to be able to use my machine and want to be able to learn the program in the future. Because I don't do this for a living I am most interested in free software and hardware under $600. I think your suggestion meets that if I go used PLC.

So if I migrate the question to how to convert from RS Logix to ccw, what are the suggestions thoughts?

drbitboy said:

I was able to convert it to micrologix 1100, there were only a half dozen OSRs in SLC that needed to be ONSs, and it downloaded without any problem to my 1100 using freebie RSLogix Micro Starter Lite.

The CCW conversion tool conversion from there to Micro820 threw some errors, but it might be rectified with some effort. Uh

Click to expand...

WOW thanks for checking that out! I tried downloading and installing the RSLogix Micro starter Lite but it did not seem to work for me. I received an error that the file needed to be rebuilt. I am sure it was operator error.

I guess the other side question now is if you see the potential error that is causing the PLC to fault? Is it worth trying to save the old SLC 500 and get it programed or should I proceed with an upgrade?

Rbelshee said:

WOW thanks for checking that out! I tried downloading and installing the RSLogix Micro starter Lite but it did not seem to work for me. I received an error that the file needed to be rebuilt. I am sure it was operator error.

I guess the other side question now is if you see the potential error that is causing the PLC to fault? Is it worth trying to save the old SLC 500 and get it programed or should I proceed with an upgrade?

Click to expand...

Yah micro starter lite does not work with SLC programs. RSLogix 500 read the SLC-based program .RSS from the .ZIP, changed the processor to the ML 1100, then saved that ML1100-based .RSS. Micro Starter Lite can read that and download it to the hardware. So you could experiment with the RSEmulate 500, which is another freebie that can emulate a ML1100.

Is it possible the SLC problem is a firmware mismatch?

Anyway, here is a.ZIP with the ML1100 PDFs, plus some .RSSs that Starter Lite should be able to open.

• The _L20.RSS suffix and Output.pdf is the SLC version; you will not be able to open that without RSLogix 500.
• The _ML1100.RSS suffix, and rss_wrapper_ml100.pdf are the RSLogix 500 translation from SLC to ML1100 processor, with the ONR-to-ONS fixes done manually.
  • The _ML1100_drbitboy_lab.RSS suffix modifies the communication configuration to match my local setup

If nothing else you can now spend a couple of hours or so validating it against the SLC-based PDF.

I already uninstalled Micro Lite, guess I should re-install thanks for doing that for me!

Will I be able to save in the format used in CCW for the conversion from Micro Lite?

I am really leaning towards the suggestions in keeping the AB architecture and upgrade to CCW like the Micro820. There is so much more content and tutorials plus it seems like a good program.

THANK YOU

First .ZIP archive is CCW/Micro820 conversion, converted from SLC files; SLC files were exported from RSLogix 500. It will not load into Micro820 because of errors; .ZIP archive a log of the conversion *_conversion_log.txt.


Second .ZIP archive of the .SLC export from RSLogix 500, so you can run the [MicroLogix to Micro800 Converter] tool in CCW.