FAQ: Failure of the DP/DP couplers after downloading the hardware configuration

QUESTION:
Why do my DP/DP couplers fail when I load my hardware configuration into the controller?

ANSWER:
You have a PROFIBUS-DP configuration in which you implement DP/DP couplers of release A2. Until now your configuration has worked perfectly. Once you change the version of STEP 7 (e.g. to STEP 7 V5.0 SP4), there no more communications come via the couplers.

Upon reinstallation of STEP 7, the GSD files of the "old" coupler modules are replaced by new ones. However, these new modules cannot be used for configuring the old modules. You can continue using the old modules if you import the GSD file contained in the download into your HW Config.

Note:
Before reinstalling STEP 7, you should always save all the GSD files that are located in the ":\Siemens\Step7\s7data\gsd\.." directory.

Download with the GSD file

sie8070a.exe ( 31 KB )

Copy the "sie8070a.exe" file into a separate directory and then start the file with a double-click . The GSD file is then unpacked automatically. Now you can import the GSD file into your HW Config following the instructions given in Below. How to integrate GSD File into STEP 7.

Keywords:
Communications abort, Master/slave communication

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How do you integrate a GSD file into the STEP 7 HW Config for PROFIBUS or PROFINET?

Instructions:
New modules are supplied in a new version of STEP 7 in the STEP 7 module catalog. The new devices can be added to the hardware catalog via GSD files.

• From STEP 7 V5.2 onwards, you can also update the module catalog with a Hardware Support Package (HSP).
• From STEP 7 V5.3 SP1 onwards you can install PROFINET GSD files in the HW Config.

Install the GSD files according to the table below.

No.	Procedure:
1	Ensure that you can access the GSD files to be integrated via the directory on your PG/PC. The files should be located on the hard disk, on a floppy disk or CD, or even in a STEP 7 project.
2	Open the HW Config and close the project opened in it.
3	Select the menu command "Options > Install GSD file...". Fig. 01
4	Browse to the file's directory in the next dialog and then click "Install". You can choose whether to search for the GSD files in the directory or in a STEP7 project. During the installation process, you may receive (error) message support (indicating, for instance, that a certain GSD file is already installed). Once the installation is complete, you can call up a record. Where necessary, use the Online Help ("Help" button). Fig. 02
5	Now update your Hardware Catalog using the menu command "Options > Update catalog". The slaves are read into the module catalog whose GSD files were installed after startup of STEP 7. Then you can incorporate the slaves in your STEP 7 project. The newly installed devices are in the Hardware Catalog. For PROFIBUS DP under "PROFIBUS DP > Other Field Devices > I/O ...". For PROFINET under "PROFINET IO > I/O ...".

Storing the GSD files on the hard disk:
You store the GSD files in the directory "\ Program Files\Siemens\Step7\S7DATA\GSD" on your hard disk.

Fig. 03

Name of the GSD file of the slave configured:
Double-click the configured slave in the Hardware Configuration. The name of the GSD file is located in the "Properties - DP slave" dialog to the right of the order number.

Fig. 04

More information on the requirements and procedure for installing, overwriting and recovering overwritten GSD files is available in the following manual:

• "Configuring Hardware and Communication Connections with STEP 7 V5.4" (Entry ID: 18652631) Section: 3.9 Working with GSD Files.

Keywords:
Generic station description file, Hardware configuration, Import

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Discussion about DP Coupler Siemens

Hello everybody,

Last few days I have been trying to understand interconnection between two master profibus networks. I have one application in wihich on one side is Step7 project but unfortenatelly on the other is PC based system which I can not monitor. Can somebody please upload one Step7 project in which DP/DP coupler is used for exchange data between two mater profibus networks.Such example would help me a lot to understand everything.

Thank you.

From your post I presume you can look into the step 7 side. If you open the hardware profile you will see the I/O devices of the PLC, inclused will be a DP Coupler.

Example below:




The picture shows the DP's hanging off the profibus, at the bottom the internal set-up for the highlighted DP.

The internal inputs and outputs are configurable as you want, to the PLC these are just I/O. Internally the PLC can just access them as normal input and outputs, alternatively you can have blocks called to multiplex data.

The other end the device (in your case the PC) would need to match opposite exactly the PLC configuration, as an Input to the PLC is an Output from the PC and vice versa.

In the end the DP acts like multiple input/output connections between devices, it needs no software comms to work, much like a normal input or output does not, you just need to set or read the I/O addresses.

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Hello and thanks for replying,

I think that I understand now, but just to be shure I am posting HW configuration of DCS that we have:



On the other side we have QCS ( quality control system). Since the firm that delivered DCS wanted to isolate their system from QCS system and they had only one spare place in the rack they decided to put CP342-5 which will communicate with QCS throught DP/DP coupler. They made one FB with for communication and used FC1 and FC2 to send and recieve data (8 IW, 8 QW and 2 statys bytes that are used). Since the DP/DP coupler is only slave on the profibus network I understand communication between CP342-5 and DP/DP coupler. Question is: if there were some more slaves on the bus how could the DP/DP know that the data is sent to it?
On the other side QCS side we have PC with Hischler card (Profibus) - ET200+AI/AO+DI/DO and DP/DP coupler. In this case what was not clear to me was the adressing part. After your reply I think that I understand that the if I put the D
P/DP on the for example Master system 1 it`s inputs and outputs are going to get unique adresses on the bus. That is why I asked for example project with code just to be shure.

One more time thank you for replying

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Hello Krcedinac.

You have put in a CP342-5 + DP/DP coupler only to make the connection between S7 and DCS.
Let me suggest to you to cut out the DP/DP coupler and let the CP342-5 be setup as a slave. The result will be the same. S7 and DCS will exchange data via i/o data areas.

Can the DCS communicate via OPC ?
In that case you dont have to let the CP342-5 be a slave, but you can exchange data from master to master.

What about the onboard MPI/DP interface ?
You can also use this if it is not being used for other things.
Especially if you can use OPC, you can set it up as MPI or Profibus and exchange data that way.

__________________
Jesper
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Hello Jasper,

Both systems DCS (not real, but called DCS, the PLC which configuration I posted and that controls the paper machine) and QCS (system that controls paper moisure and gramage and does corrections) are in warrnty period. That means that I can not change anything and I am only trying to understand how everything is functioning.Also I do not have tools and knowledge in order to change anything in the QCS system.

If I understand well, if you were constructor of the system you would cut out the DP/DP and use only CP342-5. Does this means that I should have 2 CP`s (one for each system) and then communicate via FC1 and FC2?
Considering OPC... I dont know anything about that variant and if you have time I would appriciate if you can explain me basic things or point where me to look up.

Regards,

Krcedinac
-----------------

OK, I think I understand better now. DCS and QCS are both S7 PLCs, and you are in charge of the one called DCS.
"DCS" is often used for Distibuted Control System, i.e. a system for controlling large plants, with redundancy and such things. Thats why I jumped to think you were interfacing to a DCS.

For sure, if you are not going to hang anything more on the Profibus line between DCS and QCS then all you need is one CP in each system.
There are many possible variants.
One is master-slave where the data transfer is done via i/o addresses.
Another is master-master where the data is done by messaging (PUT/GET or SEND/RECEIVE).

The only need for a DP/DP coupler is if your PLC is a DP master (maybe with DP slaves), and it shall be unaffected with what happens on the other side of the DP/DP coupler. It could be used for example if you would put the connection on the other Profibus network (your DP master system no. 1).

Anyway, you would have to at least do some minimal changes in the QCS system in order to setup the comms, no matter which solution you choose.

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Hello again Jesper,

Let`s continue. Here I am posting part of the code of the FB for data exchange between the CP342-5 and the DP/DP coupler:






So, the 16#100 (256) is the CP342-5 adress and it is sending 34 bytes and also recieving 34 bytes. Since the DP/DP coupler is the only device that we have on that network the data can go to and be recieved from DP/DP coupler. If we had more devices on this profibuse network what would happen. So far I dont see how this data that is being sent is adressed to the reciever. If you can please tell me where. I will post also CP`s propertie




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Hello again.

Quote:

If we had more devices on this profibuse network what would happen.

Then you must setup the additional slaves and assign them i/o addresses. When you download the HW config to the CPU, you also download the configuration of what i/o is assigned to which DP slave.
If you create a contigous i/o area, without gaps (Slave 1 = I20.0..I21.7, slave 2 = I22.0..I23.7), then you would only have to program one pair of DP_SEND and DP_RECV. DP_SEND and DP_RECV actually does not send anything on the Profibus network, DP_SEND and DP_RECV sends the data to the CP, and the CP in turn sends it to the configured DP slaves.
If there are gaps in the i/o area for the DP slaves (Slave 1 = I20.0..I21.7, slave 2 = I30.0..I31.7), then you would have to program several DP_SEND and DP_RECV.

I take that everything works OK by now.
In stead of posting so many screenshots, you can archive (zip) the project and post it here.

__________________
Jesper

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Setting for Replace a DP/DP Coupler Siemens

QUESTION:
How do I replace a DP/DP coupler with the order no. 6ES7 158-0AD00-0XA0 with a DP/DP coupler with the order no. 6ES7 158-0AD01-0XA0?

ANSWER:

Compatibility
The DP/DP coupler with the order number 6ES7 158-0AD01-0XA0 is compatible to the DP/DP coupler with the order number 6ES7 158-0AD00-0XA0:

• The diagnostic information for the sync and freeze mode for the coupler with the order number ...-0AD01-... has been improved in comparison to the DP/DP coupler with the order number ...-0AD00-... and correspondingly adapted to the PROFIBUS norm.
• The DP/DP coupler with the order number ...-0AD01-... can be used as a replacement for predecessor modules. The design is compatible.

Exchanging the DP/DP coupler
Follow this procedure to exchange the DP/DP coupler. The individual steps are described below.

• Transfer the switch settings
• Dismantle the old DP/DP coupler
• Mount the new DP/DP coupler

Transferring the switch settings

1. Note the PROFIBUS addresses (DIL switch 1 to 64) from the old DP/DP coupler and set the identical PROFIBUS addresses on the new DP/DP coupler. The following applies:

DP/DP coupler (...-0AD00-...)	= =	DP/DP coupler (...-0AD01-...)
DP1 (DIL switch 1 bis 64)	= =	DP1 (DIL switch 1 bis 64)
DP2 (DIL switch1 bis 64)	= =	DP2 (DIL switch 1 bis 64)
Setting "0"	= =	Setting "OFF"
Setting "1"	= =	Setting "ON"

2. Transfer the diagnostics settings from the old DP/DP coupler:

DP/DP coupler (...-0AD00-...)	= =	DP/DP coupler (...-0AD01-...)
DP1 (diagnostics)	= =	DP1 (DIA)
DP2 (diagnostics)	= =	DP2 (DIA)
Setting "0"	= =	Setting "OFF"
Setting "1"	= =	Setting "ON"

3. Set the DIL switch "PS" (Power Supply). Only the new DP/DP coupler has a "PS" DIL switch with following settings:
   • PS (DP1) to “ON”: L+/M (PS1) is connected to DC 24 V
   • PS (DP2) to “ON”: L+/M (PS2) is connected to DC 24 V

We recommend the following procedure for switching to the new DP/DP coupler:

• Connect the power supply for the DP/DP coupler to "PS (DP2)"
  (see section "Mounting the new DP/DP coupler", step 3).
• Set the PS DIL switch (DP1) to "OFF".
• Set the PS DIL switch (DP2) to "ON".
  

4. Set the DIL switch "ADDR". Only the new DP/DP coupler has a "ADDR" DIL switch with following settings:
   • ADDR to “ON”: The DP/DP coupler gets the PROFIBUS address from STEP 7.
   • ADDR to “OFF”: The DP/DP coupler gets the PROFIBUS address from the DIL switch.

We recommend the following procedure for switching to the new DP/DP coupler:

• Set the DIL switch on DP1 and DP2 to "OFF". This means that the PROFIBUS addresses will be read directly from the DIL switch.

Dismantling the old DP/DP coupler

1. Turn the power supply for the DP/DP coupler off.
2. Pull the bus connector plug out of the PROFIBUS DP interface.
3. Pull out the power supply of the defective DP/DP coupler.
4. Loosen the screws of the DP/DP coupler that secure the DP/DP coupler to the rail.
5. Swing the DP/DP coupler off the rail.

Mounting the new DP/DP coupler

1. Hang the new DP/DP coupler on the rail and swing it down.
2. Screw the DP/DP coupler tight.
3. Connect the power supply back to the DP/DP coupler. Make sure that you have made the correcting setting on the "PS" DIL switch (see section "Transferring the switch settings ", step 3) .
4. Insert the bus connector plug in the PROFIBUS DP interface.
5. Switch on the power supply for the DP/DP coupler.

Further information
A detailed description of the DP/DP coupler is available in the documentation of the DP/DP coupler.

Keywords
DP/DP coupler, exchanging, DIL switch, setting

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