Dear experts,

I have a question. I'm working with the PLC 1214C on Tia Portal v13 SP1 upd 9, another PLC that is being configured by another company and with the communication module CM 1242-5 (6GK7242-5DX30-0XE0) DP-Slave. 

I was wondering if it's possible that the DP-Master (connected to the other PLC) change a value on a tag inside the PLC 1214C (connected to the DP-Slave).

What I need to do is create a Life bit, but the problem is that the costumer wants only one tag. So, I need to send a signal from my PLC (1214C) to theirs, and they need to reset this same bit, without sending any bit back. So they need to have a write access to change the value inside my plc. Is basically I send one output bit to them, and then they reset it inside my PLC. Is that possible using this communication module? If not, is there any other possible option that I can make?

Thanks in advanced for the help

Best regards

MCRocha

Hi Duris,

Thanks for the fast answer.

The problem is that, to use the "PUT" and "GET" function I need to have a S7 connection, and I can't, because the PLC's is very distant from each other, and one of them are always moving, that's why we use the communication module and kind of a radio to transmit the information. Isn't there any other way?

Best regards

MCRocha

Sorry, it is a little bit confusing.

I need to use the communication module CM 1242-5 PB DP-Slave, and that communication module is not compatible with a s7 connection (to use GET and PUT I need a S7 connection).

Yes, there is 2 PLC's, one where I'm responsible to configure (The DP-Slave is on this one) and another who the other company will configure (the DP-master is connected to this one). For transfering the information we use the DATAEAGLE radio, but I'm not sure if that will influence my problem.

Is there any function that is compatible with Profibus, so that I can use to resolve this problem?

The master/slave exchange I already made. I created on the slave the I/O's to be exchanged. The master I didn't did because is part of the other company who has the master comms module.

The problem is that I don't want an exchange, I just want that the slave send a signal to the master, and the master change the value of the same tag inside the PLC of the slave comms module. In this particular case the master don't send any signal to the slave, he just turn the 1 from the tag "Life bit" to 0.

update: The problem is that I only have one tag "Life bit", and to use the I/O exchange I would use 2 tags, is there any way that I can always use the same tag, as input and output? Because this bit only checks if the connection between the PLC's are working

The clients want to use just one tag, that's why I'm not allowed to return with another tag the feedback of the connection.

The problem is that I need that the client PLC tells me that the connection is good. Because the HMI is connected to my PLC, what I did before was to send a signal to the client PLC, that signal reset another tag (lets call tag 2) and send it to the my plc. If the main tag (the one that is connected to my plc) stays on or off for more then 4 seconds I knew that the connection was brocken.

explaining in another words: when the tag 1 (from my plc) is on the tag 2 is off, when the tag 2 is on the tag 1 is off. But know I can't have this tag 2, because the client only want 1 tag, for some reason.

I saw a instruction that maybe works, but I still have some doubts about it, do you know the block "DPWR_DAT", and do you know if will work in my situation?

And thanks a lot for all your help

Update: Great news, I'll be able to do as you told, but the client will send to me the tag :D, thanks very much for the patience