Before RSLogix500 ver 6.0, when you go online, if the online file does not match the offline, a warning would come up. I had talked to tech support and they were able to duplicate what I was seeing. They were going to fix it in a future release.
Now, I have RSLogix500 ver. 8.0 installed. I had to create a simple two timer program to test out an new HMI that I will be using. I created the program and downloaded it into the PLC (Micrologix 1100). After I disconnected and modified the PLC program, I tried to connect again. It showed the online program without the edits. When I went offline, it showed the edits I made to the program.
Does anyone have this same issue? I would think it would be pretty severe. I would not want to go online with a project in a customers plant and find out the file I was using was no good because the customer modified it.
Do I need to setup the software in some way?

Thanks

You edited the off line file, but did not download it to the PLC. So when you went on line, you saw what was in the processor memory, not the contents of your off line file. If you don't do the download, the altered logic never gets to the processor.

I'm not sure when this feature was added but I really like it and don't consider it a flaw. It's great when visiting a customers site to do some quick troubleshooting.

When you try to go online with a processor and your file is similar, but not quite the same, it will correlate the changes with your offline file and make a temporary online image so that you can go online without uploading the program. Your outdated program is only used for descriptions at this point.

Another good example is when you are making enough program changes to a machine that you decide to do it offline, then suddenly you realize you need to go online and see how something works real quick. Instead of having to open another copy of your program, you can just go online and view the program as it currently is in the controller, then when your done, go back offline to your program with the changes you are working on

Now I'm not sure how it determines the difference between a similar program and a program that has been modified extensively enough to need uploaded.

Ken,

Yes, I realize what you are referring to. If I would go into a customers plant or connect via a modem and they modified the program without our knowledge I would have no way to know if the programs are the same if I use the same procedure I did in version 5. I could compare the programs now and see what differences there are if any.
Tech support had told me at one time, if the checksum values do not match, it should warn you the online-offline files do not match and ask you what you want to do.

Thanks

It still does if it can match the processor name up with one found in a offline file but not the checksum. This is normal. If it can't find a offline file, the only option it provides is to upload and create a new file.

Ok, this is what I expect out of the software. Version 5.# and under worked in this manner. This is the same manner all the other PLC vendor software works.

Version 5.# and below
1) Connect to PLC using RSLinx
2) Start RSLogix500.
3) Open the last known version of the PLC file.
4) Goto Comms/System Comms
5) Select the processor to connect to.
6) Select the "Online" button.
7) If the online and offlline files do not match, the software will bring up the box to prompt you if you want to create a new file or browse for the correct file.
8) If the online and offline files match, you are brought online with the processor.

Version 6 and above
1) Connect to PLC using RSLinx
2) Start RSLogix500.
3) Open the last known version of the PLC file.
4) Goto Comms/System Comms
5) Select the processor to connect to.
6) Select the "Online" button.
7) At this point, I know the offline file does not match the online since I am trying to perform this test. RSLogix will bring up the file on the PLC with the descriptions of the correct file but will not warn me the code is different.

Yes, I can compare the two files before going online if I feel they are different for some reason, but depending on the file size and if the PLC is connected to a modem on the other side of the country, this could be time consuming. At least if I am warned the files do not match, I can then compare the two files.
I have been using AB, GE, PLC Direct for 20+ years, I feel I am missing out on something. All of the other vendor software warns you the online/offline files do not match.

Why would the software allow you to go online and not warn you if the processor names match but the checksum does not??????????? I would think the checksum is much more important then the processor name match.

Thanks

ZedIDave:
Just wondering, when you are using V6 and above, if you go to Tools->Options there is a checkbox under Verification that is labeled Show Warnings. Is yours checked or unchecked? I'm not sure what this verification warning does and the help isn't too descriptive, but I think it may have something to do with this problem. I don't have a processor to go online with so I am unable to test with it on or off.

I saw what you mentioned the other day and I thought "thats it". But, after reading the help file, it is used to warn you if your code when compiled through the "Verify Project" or "Verify File" has an error.

I talked to Tech Support @ Rockwell. According to there answer ID #31769, RSLogix500 will look for a matchiing file with the same processor name. If it finds a file, it then looks at the checksum.
If the files match, the user goes directly online. If the files do not match, they may need to go to a different directory or create a new file.
Tech support was able to duplicate what I was seeing. If my online file and offline file's checksum do not match and the processor name does, it allows me to go online and see the PLC code without the changes. This should NOT happen. They told me they will fix this in a future release.