Siemens S7-300 to S7-300 data transfer

[smakdown61]

I would like to respond, but I prefer that you answer the questions posted in #10 first.

Also, PLEASE state the EXACT hardware CURRENTLY used in both PLCs. I didnt ask, but I shouldnt have to. It should be mandatory for the original poster to inform this up front.

Both CPUs are 314-2DP. Both 342-5 cards are 6GK7342-5DA01-0XE0.

Approx. distance is 50 feet.

 

[JesperMP]

OK.

Dont buy the CP342-5s.

If one PLC can be slave to the other that is master, then just use the integral DP ports on both PLCs. If the slave has to have a local HMI, use the MPI port for that purpose.
This will be fast and also doesnt cost anything extra at all.
If the data has to be transferred consistently, you can use SFC14 and SFC15.
That is all.

If both PLCs use the integral DP ports as masters, because they have DP slaves. Then add a DP coupler between the two master networks.
Apart from the DP coupler, the method is the same as the master-slave method.

Do not bother with trying to only send data when it has changed, unless you need some kind of messaging functionality.

 

[smakdown61]

OK.

Dont buy the CP342-5s.

If one PLC can be slave to the other that is master, then just use the integral DP ports on both PLCs. If the slave has to have a local HMI, use the MPI port for that purpose.
This will be fast and also doesnt cost anything extra at all.
If the data has to be transferred consistently, you can use SFC14 and SFC15.
That is all.

If both PLCs use the integral DP ports as masters, because they have DP slaves. Then add a DP coupler between the two master networks.
Apart from the DP coupler, the method is the same as the master-slave method.

Do not bother with trying to only send data when it has changed, unless you need some kind of messaging functionality.

I already have both the 342's and DP couplers. I would think the separate 342s would be faster since they wouldn't have other devices on the network?

If I want to set up the 342's to use get/put, do I configure 1 master and 1 slave in the hardware configuration or select "no dp"?

 

[JesperMP]

*sigh*

You are not sure how to accomplish the task, but you have already gone and spent quite a bit of money on hardware !?
And you have two CP342-5's and DP couplers ! And you wrote "couplers", so you have two of these too ?



Honestly, the onboard DP ports would have been enough, eventuelly with the use of one DP coupler between the two CPUs.

You could theoretically use one CP342-5 in the existing master CPU, to avoid having to change the existing master system on that CPU. But you would still have to change the HW Configuration. Notice that the performance will be somewhat lower than when using the onboard DP port.
PUT/GET will be even slower.

Future advice:
Clearly define the task to accomplish.
Investigate the possible ways to accomplish the task.
Pick one of the ways, and perfom the steps needed to finish the task (including purchasing stuff).
In that order.

 

[smakdown61]

*sigh*

You are not sure how to accomplish the task, but you have already gone and spent quite a bit of money on hardware !?
And you have two CP342-5's and DP couplers ! And you wrote "couplers", so you have two of these too ?



Honestly, the onboard DP ports would have been enough, eventuelly with the use of one DP coupler between the two CPUs.

You could theoretically use one CP342-5 in the existing master CPU, to avoid having to change the existing master system on that CPU. But you would still have to change the HW Configuration. Notice that the performance will be somewhat lower than when using the onboard DP port.
PUT/GET will be even slower.

Future advice:
Clearly define the task to accomplish.
Investigate the possible ways to accomplish the task.
Pick one of the ways, and perfom the steps needed to finish the task (including purchasing stuff).
In that order.

All the hardware is existing...I didn't buy anything. I'm just trying to figure out the best way to do it with all the options I have.

 

[KalleOlsen]

With the PUT/GET you can send several data areas from B to A, with different sources and sinks.
Using any of your DP-connections will limit it to one data area (or severlal shorter areas) limited to x bytes in each direction. You can however make your ovn overlay protocol with an index or address header.

You might also want to have a look at this link; Communication with SIMATIC S7

Kalle

 

[JesperMP]

All the hardware is existing...I didn't buy anything. I'm just trying to figure out the best way to do it with all the options I have.

Then someone else jumped too early. If these are parts from a warehouse or spare parts stock, then put them back.

With the PUT/GET you can send several data areas from B to A, with different sources and sinks.
Using any of your DP-connections will limit it to one data area (or severlal shorter areas) limited to x bytes in each direction. You can however make your ovn overlay protocol with an index or address header.

He dont need all that.
If he need to achieve something more than what he has written so far, then maybe the CP342-5's could be useful, maybe with PUT/GET or another method.

 

[smakdown61]

I'm testing to see if I can configure the 342-5 modules correctly. I have both station A and B racks in netpro with the 342-5 cards connected via a profibus network (and both addressed as 2 and 3 respectively). I went into the hardware config on Station A and created a master network on the 342-5 card and added a 342-5 slave. However, its not letting me choose the same address for the slave that I already used in netpro?

 

[KalleOlsen]

Did you check the link in #9? In the second header there is a link to a MANUAL and a PROGRAM EXAMPLE:book:.
K

 

[smakdown61]

Did you check the link in #9? In the second header there is a link to a MANUAL and a PROGRAM EXAMPLE:book:.
K

Wow I did miss that and its a GREAT example thanks!

 

[smakdown61]

Ok, so I was just thrown a sinker on this project. In the programs for Station A and B, the 342-5 cards were both configured to "No DP" and there were no connections on netpro so I assumed they weren't being used by anything else on the network. Well, I just found out there is a Wonderware Intouch station with profibus hardware already pulling data from these stations.

I am unsure if changing the configuration from "No DP" to master and slave on the stations will have any effect on the ability of the intouch station to pull data.

How can it poll the 342 cards in No DP mode? Is there anyway for me to transfer data between the two stations in No DP mode so I don't take the chance of disrupting comms to the intouch station?

EDIT: I'm in the process of finding out exactly what OPC software is being used on the Intouch station, but I would expect something similar to this http://www.kepware.com/Spec_Sheets/Hilscher_Universal.asp

 

[KalleOlsen]

It's most likely using S7 functions. In this case; proceed to the link in post #21.
K

 

[smakdown61]

It's most likely using S7 functions. In this case; proceed to the link in post #21.
K

Thanks. I noticed the actual profibus network profile was set to Universal (DB/FMS). Does that make a difference? It looks like in the examples for S7 comms it has to be set to standard.

 

[KalleOlsen]

No, this has to do with the bus timing. I think you can keep DP/FMS as this will provide longer token time (if I remember right). You can check this by looking at the watchdog time and the ttr in the bus parameters, bigger numgers are OK.
K

 

[smakdown61]

I found this example for using bsend/brcv:

BEGIN
NETWORK
TITLE =
//Set the startreq from the Input 1.0

SET ;
U "Startinput"; // Startimpulse from the Input 1.0
FP M 10.0;
= "Startflag";

SET ;
U "Startflag"; // Set the first BSEND
S "Sendreq1";
NETWORK
TITLE =
//Load the length to send for the first BSEND
L 100;
T "Send1_Length";

NETWORK
TITLE =
//The first BSEND
CALL SFB 12 , DB 12 (
REQ := "Sendreq1",
R := FALSE,
ID := W#16#1,
R_ID := DW#16#1,
DONE := "Done1_Sendreq2",
ERROR := "Error1",
STATUS := "Status1",
SD_1 := P#DB100.DBX0.0 BYTE 100,
LEN := "Send1_Length");

SET ;
U "Done1_Sendreq2";
S "Send2_REQ"; // Set the second BSEND_REQ if the first has finished with DONE ...
R "Sendreq1"; // ... and reset the first BESND_REQ

SET ;
UN "Error1"; // If an ERROR occours store the information in an MW
SPB wei1;
L "Status1";
T "History Send 1";
wei1: NOP 0;

The actual program example sits in OB1 so I'm a little unclear where all the variables like "sendreq1" etc.. are coming from? When calling the SFB what is it looking for in DB 12?