Establishing coms with a Compactlogix L31 processor

Hello, I acquired 5 AB Compactlogix racks with L31 processors. The processor batteries had been disconnected. I have not been able to establish com to the processors. Using a USB-1747-CP3 cable and RSLinks, I am able to see the complete rack, including the processor. When it scans, each node with the exception of the processor appears to be working. When I try to look at the processor using RSLinx or update the revision on the processor using Control Flash 12.00.00or Control Flash 12.00.00 in RSLinx 5000, RSLinx stops working, producing a pop up window on the computer stating the same. I also have a Ethernet connection to a AB 1761-NET-ENI to the processor. Using that connection, all I can view is the AB 1761 device. I have tried both connection on multiple racks with the same results. Any advice would be greatly appreciated. Thanks, Jim

Welcome to the PLCTalk forum community !

These are pretty old processors, the second generation of CompactLogix. The 1769-L31 had two RS-232 serial ports and relied on a battery for RAM backup. As you have seen there is no native Ethernet or USB connection.

Remove any CompactFlash cards from the processors, so that there's no risk of conflicting with an image stored on them.

When you connect to the controllers with the RSLinx browse, stop the browser at the first object under the DF1-1 driver; do not "drill down" through the controller, to the backplane, and then to the controller object in that backplane. That may resolve your issue with crashing RSLinx.

If it doesn't, post a screenshot of whatever you can, prior to the crash. My suggestion isn't going to be a lot more complex than "reinstall RSLinx Lite and ControlFlash on another computer".

Is your plan to use these CompactLogix, or are you just evaluating their condition before aftermarket sale ?

Establishing coms

I tried what you suggested on 2 of the racks and the results are the same as previously described. As seen on the processor the channel 0 green com light flashes until you try to Flash or access the processor. I have also tried the reset button on the processor with no success. My intent is to try to get the system functional and educate myself in the logic/ coding. For years I installed the field/dumb end of automated systems, lol. Hope to learn the basics. Is it possible to use a Compactlogix flash card for setup? I remember a system I worked on long ago had a flash card which was used to reload the program if the system crashed. Not sure how the info was loaded to the flash card. I thought it was out of the processor. As for the RSLINX Lite and Control Flash are presently on a Windows 7 Ultimate along with the rest of the AB programming. I downloaded Control Flash rev. 15 only to find out it isn’t supported by Windows7. If you could take a look at the pics and advise from there I would appreciated it. Thanks, Jim

Unfortunately none of those picture attachments came through. Be sure to save as a BMP or PNG file, and attach those.

Good question about the CompactFlash cards; the 1769-L31 was the unpopular little brother to the 1769-L32E and 1769-L35E controllers, all of which were the second generation of the CompactLogix, equipped with CompactFlash cards.

But in the A-B world, the flash cards have to be written by the controller's operating system, so that they contain an exact image of the firmware and user program. You can't create a flash card on your PC and then install it in a controller to upgrade or install the firmware or user program.

When I get a look at one of my Windows 7 computers I'll see what version of ControlFlash I have on there.

Security tokens

I tried to upload pics in png and bmp files. When highlighting upload a message states security tokens are missing. Not sure what if I’m doing something wrong, please advise, thanks

No idea; I've never had difficulty uploading PNG or BMP files.

Maybe host them on another service (Google drive ? Imgur ?) and link to those.

Hi Ken, I never could get the pics to upload. I took your advice an down loaded the newest version of RSLINKS on another laptop which connected and allowed me to see the processor. I removed RSLINKS on my computer then downloaded RSLINKS for Windows 7 on my computer and it connected and I can now upload to the processor. Communication is key and sometimes the obvious is not so obvious. Thanks again, Jim