Hi all!

An S7-400H (redundant PLC!) has to communicate with an S7-1500 station (S7-1515-2PN with CP1542-5) via Profibus DP. The 400H should be the master and the 1500 the slave. The idea is to realize the communication as I slave communication. The 400H is connected to a Profibus Y-link in order to connect the two Profibus lines from the 400H to the single line of the CP1542-5. Please see attached drawing. I know how to configure the I slave communication and have done it with single PLC's non redundant.       My question, is this also possible with the 400H?

I cannot test anything right now as the hardware and the commissioning will be in a few months but of course I want to be sure in advance if the hardware is able to do this.

Another idea of our customer is to put a DP/DP coupler in between the Y-link and the CP1542-5. I am unsure how that could work.

Thanks in advance for any comment!

BR, Michael

Hi Michael Pantoja!

Thank you Swarley, but I could not find anything about S7-400H with Profibus DP in both documents.

I have experience with S7-400H connected to I/O's via a Y-Link, that's no problem. But here a CP1542-5 shall be connected to the Y-Link.

You have doubts that it might work. Meanwhile I configured a Y-Link and installed the gsd file of the CP and was able to put it in the hardware config of the 400H without showing a failure. But of course that does not necessarily mean that it might work.

Hmmm 

Hi Fritz!

I just checked and yes the CP1542-5 in TIA also has this tick (only if set as DP slave, as you mentioned). So according to your words and to the FAQ's of your links it is definetly possible for the 400H to communicate to a 300 CPU or CP. Why shouldn't it then be possible to do the same with a 1500CPU respectively CP1542-5? Only difference is that there are no more DP_SEND nor DP_RCV commands available in TIA for the CP1542-5. The data mapping is done by tranfer areas, very similar to the configuration of DP/DP or PN/PN couplers, as you probably know.

As said, unfortunately testing can only be done in a few months as the system is not yet fully installed on site. However of course the software engineeing has to be prepared in advance.

Thank's a lot Fritz for your helpful comments and many links for FAQ's!

Regards,

Michael

Just received a second answer from the Siemens support.

After I reopened the case and draw the attention to the links of Fritz they now they actually agree that this should work. However they mentioned it is not directly tested from them so far. What ever that means. First answer was 'not possible'.

Ok, so I am more confident now that the S7-400H should be able to talk to the CP1542-5 via Y-Link.

In any case I will continue to inform. Of course any other comment is welcome!

Thanks,

Michael

Our end customer just told me that they did the discribed communication recently.

So I am now nearly fully confident that it should work.

Just still have to wait for the real commissioning on site.