retriving existing code form plc

[Ron Beaufort]

So can i safely conclude that there is no original code in it?

that would be the very likely ASSUMPTION ... there is still an infinitesimally remote possibility that the files have been "hidden" in some way – but I'd bet the rent that there's nothing useful there ...

have you searched DILIGENTLY for any floppy disks, CDs, etc. that might have been provided by the latest programmer as a "backup" copy? ... look in desk drawers, filing cabinets, stashed in a notebook of wiring diagrams, enclosure documentation pockets, etc. ...

 

[Lancie1]

So the ideal way to go about this is to go for an RSLinx software first, decide the version and then buy the other Rockwell products??

Not for me. If you don't have or can't find a software copy of the PLC program, then the software may not help very much. The RSLogix500 software will only help if you are prepared to reconstruct all the descriptions, symbols, and comments by figuring out how the program operates.

 

[Ron Beaufort]

So the ideal way to go about this is to go for an RSLinx software first, decide the version and then buy the other Rockwell products??

personally – I'd hire a local contractor to come in and upload the files for me ... once I had those copies in my hands, THEN I'd make my next decision ...

make sure that your contractor knows up front that you expect him to hand over valid copies of the existing program files – regardless of whether you hire him to do additional work after that critical first step has been accomplished ...

and if you're determined to do this yourself, then buy a copy of RSLogix500 (not 5000) first ... a free copy of the latest version of RSLinx (communication software) will come with the RSLogix500 package ...

once again, you do NOT have to worry about which version of RSLogix5000 to buy ... once you pay the "entry fee" for the latest version, you'll also have access to any and all other versions for at least a year ... specifically, if you call up your Allen-Bradley distributor and ask for a copy of version 13 (for example) they'll tell you that it doesn't work that way ... more specifically, you buy the LATEST version – and then you automatically have legal access to all of the older versions as part of the deal ...

then you load whichever version you really NEED onto your laptop ...

 

[yogibear87]

personally – I'd hire a local contractor to come in and upload the files for me ...

I am the new automation engineer here and just started. So its kinda my job to figure out whats going on. The system ere is very bad and there is no record of plc logic, all i have is an old wiring schematic.

 

[yogibear87]

I am hoping to figure it out with a couple of maintainence guys. It is a long process but i am hoping it is doable

 

[Lancie1]

The system here is very bad and there is no record of plc logic. All I have is an old wiring schematic.

It might save you a lot of grief to FIRST exhaust all possibilities that the old program does not exist - out there somewhere. The former automation engineer may have a copy on an old laptop, or one of the maintenance may have a copy, or know where one is. A former outside electrical contractor could have a copy, or a copy of the wiring connection drawings (which would show and label the PLC inputs and outputs).

I once was able to get some PLC program files from a former electrican who had been fired a year previously for stealing from the company. All he wanted was a little sympathy and a little money under the table. The $50 was a bargain from my own pocket, and saved several months of pain. I got not only the PLC program, but also the original copy of the RSLogix software and floppy key disk that the company had paid for, but never knew was missing.

 

[yogibear87]

I have a ladder-wiring diagram (NOTE: not PLC ladder logic). The problem is it is old an outdated. Unfortunatley i am the first automation engineer in this company! (Yup, quite the pickle!)

Is the uploading and figuring out very hard to do? (my major project is starting in 2 months and i have time to kill)

 

[Lancie1]

Yogi,

The wiring diagram will be a place to start. With it and the help of the mechanics, you will eventually be able to figure out all the Input and Output addresses. It will not help with the PLC internal addresses, which the program will have but will not identify as to what they do.

Uploading the old program would be the easiest part. The figuring out how it operates will depend on your knowledge, your experience with similar equipment, and how fast you can learn new subjects.

To be honest, it sounds to me like you want to go the "challenge" route of rewriting the old program, as opposed to the more logical and potentially less-personally-rewarding route of finding the old copy. Possibly you are thinking that the only copy available would be inside your company. No, it could be anywhere in the world, and you must be willing to do what it takes to find it.

I once needed to track down the wiring diagram for a 50-year-old car crusher, so that it could be put back into service after many years sitting idle. The company had been out of business for 20 years, but after many phone calls, I found the guy who built the machine, now working at a different place. He did not have the wiring diagram, but he could remember exactly what each wire did, so I was able to redraw the schematic by probing his memory on the phone!

 

[Ron Beaufort]

Is the uploading and figuring out very hard to do?

it's sort of like doing brain surgery – or just tying your shoe ... in other words, once you UNDERSTAND something, then DOING it is not usually all that hard ...

but ...

answer these and then we can go further:

(1) is there already something (anything?) plugged into the DB9 connector on the front of the SLC processor? .... for example: a cable running to the HMI device, etc. ...

(2) is there already something (anything?) plugged into the DB9 connector on the front of the CompactLogic processor? .... for example: a cable running to the HMI device, etc. ...

if the answer is "yes" to either one of those questions, then your problem could have just become exponentially harder ... the reason is that those ports are NORMALLY used for programming – and for uploading and downloading operations ... BUT ... those ports can also be re-configured as COMMUNICATION ports to connect to other (non-laptop) devices ... that means that you probably won't be able to just plug in a simple cable and do the upload ...

(my major project is starting in 2 months and i have time to kill)

if you're in this for the long-haul, my advice is to talk to your Allen-Bradley distributor about your situation ... buy enough hardware and software to put together a spare system ...

maybe the distributor will be able to come out and help you with your problem and give you some tips on how to proceed ... (I worked for an AB distributor for about 8 years – and "customer relations" visits like this were a very common part of what I did) ...

once you've got some hardware and software to play with (sorry, I meant to say WORK with) you'll take a LOT of the pressure off of yourself – and your company – not only for this project but for all of the others in the future ...

 

[Ken Roach]

If I was in your shoes, I would get in touch with my local A-B distributor and invite their "PLC Specialist" to visit your company.

Explain your situation as the new automation guy, and ask for his help in uploading, saving, and printing the PLC programs. These are absolutely trivial tasks for one of those guys.

In return, ask him for a quote on the proper RSLogix software you will need for maintenance and modification of your control systems. There may also be RSNetworx or RSView or other software packages you have or need. He'll be able to have a search done for Rockwell software that might already be registered to your company (RA's records go back decades) but have been lost or forgotten. Renewing support is a lot cheaper than buying new copies.

A lot of end-users don't realize how precious a "new or returning customer" is to a Sales guy or a technical specialist. These guys have quotas or bonuses that rely on getting new customers, and even putting his visit into a monthly report is a big gold star for him.

I did this all the time when that was my job. I didn't leave the gate until I had shaken the hands of the Purchasing Manager, the Maintenance Manager, and if possible the General Manager. Even if those were all the same guy.

 

[yogibear87]

Ok. I am going to go ahead and get the ABB distributor over.

Wow, Thank you so much for all your help!! Being fresh out of college I had no idea i had so many options to solve a problem and thought everything should be done by myself!

Thank you so much!! much appreciated!! I will keep everyone informed of the situation here.

 

[Lancie1]

Being fresh out of college I had no idea i had so many options to solve a problem and thought everything should be done by myself!

Yes, after some experience, you will realize that there are a few things you can do efficiently yourself, and many other things where it makes sense to get someone else to do it faster and better.

The Allen Bradley distributor will be compelled to give you some sales talk along with help, so be prepared with a lot of no's or a big expense account.

 

[Ron Beaufort]

careful ... it's AB (Allen-Bradley) ...

ABB is another company (Asea Brown Boveri) ...

this is like accidentally calling your new girlfriend by your ex-wife's name ...

good luck – and let us know how it turns out ...

 

[yogibear87]

careful ... it's AB ...

ABB is another company ...

this is like calling your new girlfriend by your ex-wife's name ...

good luck – and let us know how it turns out ...

Sorry! i knew that...purely typo!