4/24/2015 9:42 PM | |
Joined: 9/27/2006 Last visit: 4/26/2024 Posts: 12257 Rating: (2665) |
Hello matwon; As a quick answer: Two Profibus masters can coexist with their own slaves on the same Profibus cables. Logically though, each master with its slaves should be treated as a sepperate network. The easiest way to share information between 2 masters on such a configuration would be to use a DP/DP coupler. Have a look at the following FAQ: What are the special features of input/output addressing with the DP/DP coupler?
Daniel Chartier Edit: The part number for the DP/DP coupler has been mangled in the link above (but it is correct in the manual you can download there). It should be: 6ES7 158-0AD01-0XA0 Hope this helps, D.C. |
Last edited by: dchartier at: 4/24/2015 9:50:37 PMLast edited by: dchartier at: 4/24/2015 10:47:14 PM |
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4/25/2015 3:12 PM | |
Joined: 5/24/2012 Last visit: 2/19/2024 Posts: 70 Rating: (0) |
Ok thanks I'll look into it! |
4/27/2015 10:29 PM | |
Joined: 5/24/2012 Last visit: 2/19/2024 Posts: 70 Rating: (0) |
Is there any other way without the DP/DP coupler? |
4/27/2015 11:17 PM | |
Joined: 9/27/2006 Last visit: 4/26/2024 Posts: 12257 Rating: (2665) |
Hello matwon; Again, quick answers tio your short question.é Profibus networks can easily handle master-slave cyclic connections, or master-master acyclic connections: What master/slave communication options are available on PROFIBUS DP? To setup a master-slave connection between your 2 PLCs, one of them must have a slave interface 9and be correctly configured). But Proifbus interfaces can act either as master or as slave, so you will need a CP 342-5 on the rack as a second interface that can be setup as slave (the CPU's integrated interface wil still be used as a master connection). To setup master-master conncetions, you must use specialized interfaces 9the CPU's integrated interface cannot be used for S7 Connections or FDL functions). These specialized interfaces happen to be also CP 342-5, so for this connection you would need 2 of the CPs in all.And you will have to program communication function blocks (This is the "acyclic" part) between the 2 CPs in your project: Or you can agree that it is simpler to use a DP/DP coupler to setup exchanges between 2 Profibus-DP masters, as suggested earlier... Hope this helps, Daniel Chartier |
4/28/2015 7:17 AM | |
Joined: 10/7/2005 Last visit: 4/26/2024 Posts: 3004 Rating: (1046)
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Just an additional thought from my side: The S7-1200's CM1243-5 supports S7 communication as a Server as well as a Client. The S7 -300 CPU's onboard DP ports supports S7 communication as a Server (but NOT as a Client). You could as such physically link the two Profibus Networks together and use GET/PUT in the S7-1200 to read/write data from/to the S7-300. You'll need to be aware though that you now have all DP Slaves and two DP Masters on the same physical Profibus Network and make sure that each device has a unique node address. You also need to check that the bus timings are the same in both DP masters. While the advantage of this is that you do not need any additional hardware, I personally would opt for Daniel's suggested (and arguably more elegant) DP/DP coupler solution (which also keeps both DP Master Networks separate from each other). I hope this helps |
Cheers |
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3/29/2017 12:45 PM | |
Joined: 9/3/2014 Last visit: 3/13/2019 Posts: 4774 Rating: (123) |
New question published by Gilangmustofa95 is split to a separate thread with the subject Addressing of two masters in PLC program. Best regards |
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