Using an extrenal "permissive" to open a pop-up window

I have an application where the customer would like to have a window (pop up/faceplate) open given certain states of field devices. For example if the PLC receives a certain pressure from a transmitter, or feed back from a valve position switch.

Also, under certain conditions if the pop up is active, valves may force open or closed.

So..can this be done? Using a Allen Bradley Compact Logix and PanelView HMI.

Thanks!

Burch

It sure can. You would just use the visibility of the object to determine when the object is to show up on the screen. You can tie that to a tag so when a tag is true then the object will show up.

If you want to open a popup window based on tags in the PLC, you need to use the display number and global connections. Have a read up on both of those - essentially, you assign all of your displays a unique number in the Display Properties page, set up a tag in your global connections to be a "go to screen" tag, and then use your PLC to write the desired screen number into that tag.

An important thing to remember, is that while your PLC is calling for "screen 5", the operator can't change to any other screen - it's locked to screen 5. In the global connections you can also specify a tag to be "current screen number" - basically the HMI writes the current screen number to this tag. I generally use this as a handshake - my PLC calls for screen 5, once I see that it's displaying screen 5, I call for "screen 0" again (calling for "screen 0" gives the screen control back to the operator).

Hopefully that'll get you started!