Comunication from Citect 7.2 to Siemens S7-300

[spiritovivo]

Hi everybody
I have a (big) problem with Citect & my Siemens PLC.

I use CitectSCADA 7.20 / Simatic 5.5 and my PLC is S7-CPU317etcetc

I've download the Siemens Industrial Ethernet driver on www.proscada.com to configure the ethernet connection.

If I go on runtime with my Citect Project I can read the changes of my tags (if I change a bit status in a VAT table on my Simatic manager I see everything on my citect project).
BUT if I try to change the bit status from my citect project the information doesn't arrive on my PLC (and it doesn't arrive in simatic too, obviously).

What can I do?

(I'm sorry I know my english is very bad )

 

[spiritovivo]

helloooo...?!

 

[uptown47]

Are you 100% sure it's not changing. Are you displaying the actual 'bit' from the plc and then toggling that? It's really strange to work one way and not the other???

 

[spiritovivo]

Are you 100% sure it's not changing. Are you displaying the actual 'bit' from the plc and then toggling that? It's really strange to work one way and not the other???

I know that it's strange but that's the way it is!
I also try with a word variable: when I change it from my Simatic Vat Table I see my value in Citect. When I try to change the same tag I don't see any change in my Vat Table and in my FB while checking! I don't know what is the problem, it colud be a really stupid thing that I still don't know...!

 

[spiritovivo]

is there anybody who can help me?

 

[andybutcher]

I can attempt to help. You can read the S7 OK, so it sounds like your comms are OK.

How are you trying to change the bit in Citect?

 

[uptown47]

Have you tried displaying the 'bit' in 2 places on the screen. Then change one of them and see if it changes in the PLC and changes in the other position on the screen?

 

[spiritovivo]

I can attempt to help. You can read the S7 OK, so it sounds like your comms are OK.

How are you trying to change the bit in Citect?

With a normal bottom, if I push it the command is "MyTag=1"

I think that the comunication is ok (otherwise I can't see the bit changes in Citect!)

Maybe I have to write a particular cicode? I really don't know, I don't know what to do!

 

[spiritovivo]

Have you tried displaying the 'bit' in 2 places on the screen. Then change one of them and see if it changes in the PLC and changes in the other position on the screen?

When I change the bit from simatic (or from a push button that I have here on my desk and which is connect at my DI slave) I see that changes in Citect, everything works! But when I try to change a bitstatus from Citect it doesn't work. If I try to change a bitstatus of a internal tag of Citect it works obviously!

 

[andybutcher]

OK. Well that should set your bit high when the button is pressed. Another command you can use is Toggle(My Tag) this command will change the state of the tag from 1 to 0 or 0 to 1 on each press of the button.

Another thing you can try is add a button on the page and call a function called TagDebug(). This function will display a list of your tags or you can type them in and allow you to write or read the tags.

All of these functions are explained in the Citect help file. They usually have examples as well. The only other thing I can think of is that your opc server is working as read only. We use simatic net opc with Citect on our sites and it works well. Unfortunately I have not used proscada. But I'm sure the principals are the same.

 

[spiritovivo]

OK. Well that should set your bit high when the button is pressed. Another command you can use is Toggle(My Tag) this command will change the state of the tag from 1 to 0 or 0 to 1 on each press of the button.

Another thing you can try is add a button on the page and call a function called TagDebug(). This function will display a list of your tags or you can type them in and allow you to write or read the tags.

All of these functions are explained in the Citect help file. They usually have examples as well. The only other thing I can think of is that your opc server is working as read only. We use simatic net opc with Citect on our sites and it works well. Unfortunately I have not used proscada. But I'm sure the principals are the same.

I already knew thw "Toggle" function, but I didn't know the function TagDebug, thanks! This doesn't resolve my problems but it's extremely useful.

The problem is that I can't understand if my OPC server is working as read only. I would focus only on it if I found out that the problem is there! I have also called a Siemens operator and he told me that the problem is certainly or in Citect or in Proscada

 

[andybutcher]

It is probably more to do with ProScada. From what I have read, you have to define the data areas you want to make available from the PLC. Maybe the area you are trying to work with is defined as read only?

As I mentioned before, we have successfully used Citect with Siemens PLC's on many of our sites. The difference is that we use SimaticNet as our OPC server.

 

[andybutcher]

Also, check the driver from the Kernel window. This might give you some clues if you get errors when you write to the tag.

 

[spiritovivo]

I SOLVED MY PROBLEM!

I went in Computer Setup Editor, then in System Parameter Listing, then in LAN Parameters, then in [LAN]SecureLogin and I must set value to 0 to write the values. For Citect 7.2 is indispensable

 

[uptown47]

Great news. Well done and thanks for posting the answer back so that it will help other people in the same situation in the future. ;-))