PLC Backup

Hello everyone,

Although I have a little experience with ladder programming, I'm new with PLCs.

I need to download the program on an Allen Bradley SLC 5/02 PLC, to my computer as a backup. I've tried with a serial cable and RSLogix 8.10 but when I tried to upload the message "Communication Path has not yet been configured" pops up, followed by the Controller Communications in the Controller Properties window.

There, I have to select a driver, but the only option available is (unknown) and from there I don't know what to do...

So can someone please explain me step by step, how to make a backup of the existing program on an Allen Bradley PLC? What cable and software do I need? In what mode must the plc be?

Thanks!

Your SLC5/02 only supports DH485 protocol. You will need a 1747-PIC ( old device) which requires a real serial port on your PC. Or the newer 1747-UIC (USB to DH485 converter). Do you have one of these? If so let us know then someone can help you setup RSLinx to communicate with your SLC5/02.

What cable did you try to use? The SLC5/02 does not have a serial port.

Mickey thanks for your answer.

I connected the PC to channel 0 (which is a DB25 connector) in the PLC by a cable thats DB25 on one end and USB on the other, that's why I assumed it was serial, if I'm wrong please correct me as those are the kind of things I'd like to learn.

I don't have any other cable, so tell me if I'll be able to do it with the one I have.

Why do you tell me about RSlinx? I thought I only needed RSLogix to download or upload a program, am I wrong in this too??? Sorry if I look like a complete ignorant, well...I am!

Thanks again

I'm sorry, the plc is 5/20 not 02!

EDIT: RSLinx is the communcation software package that Allen-Bradley uses to talk to darn near everything they make. It has several flavors, and the Lite version is free, on almost every Allen Bradley software CD, and can be gotten from the web.

Well, the 25 pin port on a 5/20 is RS232 and speaks Allen-Bradley DF1 protocol (by default). This is good news, since you don't need an expensive converter to talk to it.

Now, we need to know more about the USB to serial converter you're using in order to know if it's right.

I haven't used a USB-serial converter, so I don't want to steer you down the wrong path, but I think the basic instructions are going to be the same as if it were a real serial port, with the possible exception of the COM number used by windows. This picture should help, and make sure your cable is hooked up when you hit Autoconfigure, then let us know if you have more problems.

Tell us more about this USB to serial adapter you have. I have never seen one with 25 pin to USB before. They are usually 9 pin to USB.
You will still need a null-modem adapter on the end of your Serial to USB adapter.

If your PC does not have a real serial port and you need a Serial to USB adapter that we all know works see link below.
Brand "keyspan" scroll down right hand side.

http://www.plctrainer.net/

My guess is that a 25-pin to USB converter that has a permanently attached cable is actually a Parallel to USB interface, rather than serial. I have only one very old USB/RS232 25-pin unit and haven't seen such a thing in many years.

You'll have to verify that, probably by using the device part number and/or the Ports section of the Windows Device Manager.

Rockwell Automation sells three software packages that share the "RSLogix" name:

RSLogix 5 is for PLC-5 family controllers, including your PLC-5/20.
RSLogix 500 is for MicroLogix and SLC-500 family controllers.
RSLogix 5000 is for ControlLogix family controllers.

The only one of these software products that has had a version 8.10 is RSLogix 500. This won't work with your PLC-5 controller; you need RSLogix 5.

This should help you.

Well, thanks for all the info people! I hope I'll be able to help someone here as well someday!

That RSLinx guide has been really helpful and now I'm waiting to go and check if things workout. I downloaded RSLinx lite and hope it works alright with what I'm trying to do.

I want to clarify the issue about the cable. This has a DB25 on one and and a DB9 on the other. (only pins 2,3 and 7 connected (Rx, Tx and ground) on DB25). Then DB9 is connected to a Serial-USB adapter, and then a USB printer cable (Type A and Type B plugs) from it. I didn't explain this at the beginning thinking it was not necessary.

Just in case you don't know, although I believe you all do: This adapter lets you connect a serial device to a USB port and your PC sees it as a new serial Port (if you look in your device list, you will see a new COMx port) and you use it just like a normal serial port. Nothing fancy there.

Now, according to the guide bornwild posted, "Channel 0 is a 25-pin serial port" and as OkiePC explained, it speaks de DF1 protocol.

So those are the news by now. I hope I can test this sometime this morning, and I'll post here my results.

Thanks to everyone again!

Well I'm not so proud to say I had no luck...

I could establish a connection with RSLinx though, but couldn't upload the program in the processor with RSLogix. I'll show you what happened:

The first image is the configuration screen in RSLinx, everything seems OK to me.

The second is in RSLogix trying to configure the communication, it asks me for a Node number (?). I tryied with 0 and 1 but it seems I can only insert a value between 0 and -1 as shown in the second pic.(?????)

Now, I tried with -1, and then the node field blocks (it turns grey, and I cannot write there anymore, and when I try to apply the changes it asks for a node number between 0 and 77 octal (???????????!!!!). But there's no place where to write it!

PLEASE HELP ME!!!, or a couple of PLCs may get slightly injured...

1) That first picture proves that RSLinx and your cable are just fine which is 9/10 of the battle.

2) Tell us you are using RSLogix5, (not 500)?

3)Don't worry about system settings in RSLogix5, just go to the menu bar and find Comms > Who Active Go Online. That will pop up a RSWho window and your already configured driver and PLC should appear there...

4) When it tries to go online, RSLogix will look for a matching file. If you have one that is a good match (same online processor name and program checksum) it will go right online and load that file (with its comments and symbols). If it does not find a good match, you can browse to a file which can be used and then you'll choose Upload Use File. If you have no chance of finding an old file with comments and symbols, then you can choose Create New File. This is still good enough for a backup, but will not have any symbols or comments.

Well thanks, I'm going to try that right now (although I think I already did.)

But no, I'm using RSLogix 500 v8.10, is that fine?

Frelecing said:

But no, I'm using RSLogix 500 v8.10, is that fine?

Click to expand...

Nope.
That software is only good for SLC and Micrologix PLCs. You must get your hands on RSLogix5.

Well, thanks to all of you once again. But, I continue with same problems.

Now i'm using RSLogix 5 v7.30.10, but I'm having no luck either. It keeps asking me for the node number between 0 and 77 but it also adds that the only valid values are between o and -1. I can't understand this at all...

Another thing that I should clarify is that the PLC is in REM mode, is this OK or should I change it in order to establish the communication?

The pics are of the message I get in RSLogix, and of the PLC I'm talking about, just in case you see something I should change, as I told at the beggining, I'm new with all of this.

Thanks one more time, and I hope my next message is to tell you I could upload the program!