1756-L72 processor front panel messages

[macgyverhd]

Hello all.... I am not asking you to fix my issue just a little guidance is all i am asking. I just started with a new company and I am working on a stand alone PLC/PV system which also has a Rockwell ems08 switch involved. I tried to set the IP addresses of the HMI and PLC to our process network and remove the em08 switch and when i did i got a message on the front of the PLC that the switch was no longer found. I have never used any type of messaging, what I am asking for is some guidance of what/where to look for to resolve this. Thanks in advance for your support

 

[Operaghost]

It sounds like the switch was part of the PLC I/O Configuration.

If you go online to your PLC look at the Online toolbar and see if i says "I/O Not Responding" and you probably would see a flashing green I/O indicator on that toolbar. If you do see this, look in the I/O Config and see if there is a little yellow triangle next to the Ethernet switch. If you see it then that is the problem.

You can then double-click on the switch and on the Properties tab (I think that is what it is called....the second tab) you can select to inhibit the device. That will tell the controller to halt all attempts to communicate with that device.

The larger problem is that your PLC may have had logic connected to this switch. Likewise, your HMI may have screens to display information from the switch.

OG

 

[Phil Buchanan]

Most of the switch units in the Stratix family can be tightly integrated with logix such as when someone plugs a device into a switch port you can have logix shut down the entire production line if you wish just as an example.

The way they get this functionality is by treating the switch like an intelligent I/O device just like a VFD drive or a remote chassis of I/O.

Just because you have this I/O fault message does not necessarily mean the system won't run. If the device is not being used in the program code and the system is not set to fault the processor upon an I/O fault (they are normally not by default) then it may run as is.

To clear up this message if you are not going to use the EMS08 switch any longer you will need to remove it from the I/O tree in the program which should clear up this mesage as the system will no longer be looking for it once it's removed.

Another option is to give the switch an IP address on your process network and modify it in the I/O tree and leave the switch in place.

Not sure about your physical layout but how will you connect the PLC and HMI to your process network physically without the switch? Are you connecting them in a linear topology?

 

[macgyverhd]

@ Phil Buchanan... my intentions were to use a different switch that has 2 fiber ports along with 6 copper ports. I need two fiber ports so that I can link a satellite station in as well. On top of all of this I am changing the IP addresses of the PLC and 2 panelviews to merge onto our process network. Hope this helps you and I will also look into your suggestions. Richard

 

[Phil Buchanan]

@ Phil Buchanan... my intentions were to use a different switch that has 2 fiber ports along with 6 copper ports. I need two fiber ports so that I can link a satellite station in as well. On top of all of this I am changing the IP addresses of the PLC and 2 panelviews to merge onto our process network. Hope this helps you and I will also look into your suggestions. Richard

If your new switch is not a statix then just remove it from the I/O tree. You may want to make sure none of the switch integration features are used in your logix program and also that the switch faceplate is not being used in your HMI application. Look around well on your HMI application because many people will put the switch faceplate on a hidden / password protected maintenance screen.

So in short you may want to do a little investigation before you pull the trigger.