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WinCC Communication Problem with PLC

Created by: Krish at: 4/23/2008 12:52 AM (6 Replies)

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4/23/2008 12:52 AM	Rate (0)
Krish Silver Member Joined: 5/24/2007 Last visit: 4/24/2024 Posts: 284 Rating: (27)	We are using WinCC 6.2 for a project which is connected to 8 PLCs. 7 of them are 416-2 PLCs while one of them is 317-2. The communication is ok with all the other PLCs . But we are having trouble with the 317-2 CPU. We are able to read and write the binary tags. But other tags we cannot see any value or enter. The field appear in gray color on the HMI. We have checked all possible issues that we know about. For example 1. No error message in the diagnostics files in the WinCC directory. 2. PLC communication settings were set upto 50% of communication load. 3. Assigned 12 connection only for OP communication. but only2 are used. 4. Tried all combination of system parameters for Industria lEthernet communication. It would be helpful for us if somebody is aware of such a problem or is aware about the precaution to be taken with mixture of PLCs in the HMI System. Any other suggestions on what else we could do it establish the connections again would be very welcome. Thanks

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4/23/2008 6:05 AM	Rate (0)
aikona Posts: 487 Rating: (36)	Krish Have a look at the firmware revision and see if there are new upgrades .I got the same problem with a 315 , one works the other one not and the only difference is the firmware version.As soon as we can stop the PLC we going to upgrade. Sorry that all I can give you. Eric
aikona Posts: 487 Rating: (36)
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4/23/2008 10:29 AM	Rate (0)
Krish Silver Member Joined: 5/24/2007 Last visit: 4/24/2024 Posts: 284 Rating: (27)	Thanks for the tip, Aikona. But it did not help. We had firmware 2.6.0 and we loaded the new 2.6.5. But the situation is still the same.Thanks in any case

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4/24/2008 10:52 AM	Rate (0)
perdahlqvist Gold Member Joined: 10/26/2005 Last visit: 11/27/2024 Posts: 284 Rating: (50)	Hi! If, you use a script, “dynamic dialog” or “C” or “VBS”, then the status of the tagg in question can perhaps give a explanation to the non working values. More help is on your pc with wincc: For "VBS" “WinCC Information System” -> "Working With WinCC” -> “VBS for creating procedures and actions” -> “Examples of VB Script” -> “Examples in WinCC” -> “How to read tag values” Scroll down to: “Reading with status handling” For “C”, use function: “GetTagFloatStateQC” or “GetTagFloatState" In "Dynamic dialog", set “Tag status” or “Quality Code” This is a good start in finding the real fault, I belive...

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4/24/2008 11:59 AM	Rate (1)
Jeebs Posts: 218 Rating: (28)	Hi, Your problem can be either faulty comms or incorrect setup. To find out which of the 2 it is will be very easy. Start the runtime. Check in Tools > Driver connection if the Connection is built up. If yes, then navigate to the S7-317 taglist. Find a tag of which you are 100% sure it should have a value >0. Hover your mouse over it and wait for the ToolTip to show. This will give you important information such as the current tag value and the quality code. Is the tag value in this tooltip >0? If the answer to either of the questions is NO, then you have comms problems. If the answer to both are YES, then your IO-field is not configured correctly. If this is the case check your settings, especially check wether the IO-field is decimal and configured ranges is large enough. (if value is 4521 and range is 999,999 it will NOT show) The tag update should've been checked..:D As you say that binary tags are ok, I presume the comms are ok and the real problem would be the io-fields/configuration. Jeebs
Jeebs Posts: 218 Rating: (28)
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4/24/2008 5:49 PM	Rate (0)
Khaled_Ezzat Silver Member Joined: 9/7/2007 Last visit: 10/9/2024 Posts: 550 Rating: (62)	try to connect the 317 CPU only and check the tags that confuses you, some time the data block is not created or the tag format is wrong check this it may helps you
	Best Regards
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4/24/2008 6:44 PM	Rate (0)
Krish Silver Member Joined: 5/24/2007 Last visit: 4/24/2024 Posts: 284 Rating: (27)	Thanks a lot gentlemen I tried all tricks of the trade that I knew and those that you all suggested plus many others whom I troubled.But nothing worked. Just to put down a few of the observations. 1. The tag quality shows bad. 2. On the Tag Explorer also these tags show the same. 3. All digital (binary tags) are fine irrespective of where they are in a DB(in range of addresses) or DB numbers. 4. Someinputs areshow blinking whenparameter in the DriverConection is set to PLC cyclic update. Wehave taken this up with Siemens Support serviceusing the Automation Value Card.So when we get reply/solution I will put it down in this forum for everybody´s information.Who knows it could be a terrific bug or a big blind spot in our teams´ brains!!!!

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