I was wondering if anyone can think of a solution to displaying the "keyswitch" in program mode on a GDU. The logic is all there the problem is that the PLC isn't scanning the logic in program mode. Any clever solutions?

Not sure what a GDU is... but I have done something similar on a SCADA before... you just need the bit/tag to be high (true), when you are in RUN a 'dummy' bit/tag will be true, when you are in program all outputs are false so have that (the output) set the bit...

Unless we are not talking about the same thing.

Hope this helps
Mark

"GDU" = Graphical Display Unit?

Depending on your "flavor" of AB PLC the keyswitch state is a readable status bit and the GDU can have an animated object basaed off this status bit.

BTW what PLC and GDU would be helpful.

Here's one method that I have used with ControlLogix and PanelView Plus or RSView.

RSLinx Classic and RSLinx Enterprise both have Pre-Defined Items that you can use in OPC or FactoryTalk clients.

The pre-defined item [Topic]@Mode is a string that returns Run / Remote Run / Remote Program / Program. You can put this in a graphic as a string display, or use its string values to animate a picture of the keyswitch.

1756-L61 PLC with a XYCOM/PROFACE AGP-3600T GDU. So you are saying it is a status bit that can always be read? If that is the case I should be able to just use the GDU to look at that/those bits. Let me know if you have some more exact info since I gave you some more exact info.

Your ProFace terminal does not use RSLinx Enterprise or RSLinx Classic, so it cannot make use of those data servers' pre-defined OPC items.

The ControlLogix family of controllers have status and diagnostic Objects, rather than "Status bits" like the PLC-5 and SLC-500 controllers.

You can get these objects' data into your operator interface by using message or GSV instructions to put the data values into Tags, or you can use a data server that is aware of the Logix family's object model.

Proface/Xycom being a competitor of Rockwell Automation's, I doubt that they have put in support for ControlLogix specific data objects.

In short: With Proface, talking to ControlLogix, you can't get the keyswitch mode or controller mode except when it's executing a control program.

I did a project 2 almost 3 years ago connecting 132 XYCOM GDU's to a 1761-L63 CPU. yes I did not type we hooked 132 XYCOMS thru seven 1761-ENBT's to an L63.

That particular XYCom read using PLC 5 style addressing and we had to map all tags to PLC 5 type addresses.

Ken is quite correct that you'll probably not be able with an XYCom to detect keyswitch state.

The only work around I can envision is if you are using a high enough level XYCom to have macro capability. You could use the state of the tag being updated and if not updated assume key in program.

The problem with using heartbeats between the PLC and XYCOM is knowing whether the PLC is in program mode or is faulted

I may not be able to detect the keyswitch position, but I be I can come very close. All you need is a spare output that the XYCOM can read the state of. In the program make an unconditional rung that contains this output. Configure the output to be OFF in program mode and ON in fault mode.

This will give you a RUN/PROGRAM mode indicator. Then add a GSV to keyswitch and you should be able to determine the true keyswitch position

This seems like a good solution. In the past we have used the heartbeat to determine the state but like you said this isn't truly program mode, it could be faulted. The Proface unit is pretty good talking with the Logix 5000, it takes a direct import of the .L5K file and uses that as the tags in the GDU. This issue is not imparative I was just hoping that we could come up with something, the output is probably the best solution I will let you know what I end up doing, it may be one of those things that I don't worry about because it is on a screen that no one besides me will probably look at. Plus most people just open the cabinet to look at the PLC instead of using the screens that I have spent hours developing.