WinCC tag from 1 plc to another

Hello all, I was wondering how to go about having 2 plc's communicate thru my touch panel. I have a MP-270 touchpanel running WinCC flexible 2005 Advanced. The HMI has a connection to each but neither PLC to the other. Is it possible to have an Input turn on a tag for that connection than have this tag turn on another tag that is read from the second PLC. It seems like an easy idea but I'm stumped.

Thanks,
-Joel

I don't know how fast it would be but I think it would work. Take the first tag and on change set value of the other tag. It gets a little more complex with bits but words and ints should be easy.

Is it possible to have an Input turn on a tag for that connection than have this tag turn on another tag that is read from the second PLC.

Click to expand...

"...written to...", surely? Or have we misunderstood you?

Ken

If the dataexchange between the two PLCs is critical, then maybe going over the HMI panel is not so smart. But CharlesM's suggestion should work in priciple.

Maybe it would be possible to setup a direct connection between the two PLCs.
What exactly are the PLCs (and CPs) ? What connection type ?

It's not very critical. The system contains (2) CPU 315's and an MP270. I was just trying to find a quick and easy way to find out if a prox is on, on the first system before motion occurs on the next.