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CPU314C-2DP OB1 Issue

Created by: kwl at: 1/5/2009 9:30 PM (7 Replies)

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1/5/2009 9:30 PM	Rate (0)
kwl Posts: 3 Rating: (0)	I have a CPU314c-2DP and I have been having some issues with it . To resolve I have done a RESET TO FACTORY as outlined in the operation manuals for the 31X CPU's, I have also reset the MMC which doesn't appear to do anything. Items: STEP 7 V5.4 SP4 CPU314C-2DP V2.0.12 EATON SVX9000 DRIVE WITH PROFIBUS CARDS ET200S REMOTE IO My problem is now that I have reset the CPU to factory the program will not execute, I have done the following to try and resolve - I have loaded a blank config with just the OB1 in it -Verified it was empty by viewing online - Loaded a previously working version to the CPU - Viewed this online to confirm that the program was there - monitored OB1 and the PLC isn't executing - The only block showing anykind of online monitoring is the OB1 ALL other FB's state that they are not being executed(obviously since OB1 not cycling nothing else in the program will) I'm pretty new to the S7-300 stuff so I think that I'm missing something obvious here. Is there a setting in the CPU after reseting to factory? Is there a mystery function block that I am missing Should I upgrade the Firmware to V2.6.6 (Don't have the PG to do this) Is the MMC bad?
kwl Posts: 3 Rating: (0)
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1/5/2009 9:49 PM	Rate (0)
IBN-Service Posts: 8946 Rating: (999)	kwl I have a CPU314c-2DP and I have been having some issues with it . To resolve I have done a RESET TO FACTORY as outlined in the operation manuals for the 31X CPU's, I have also reset the MMC which doesn't appear to do anything. Items: STEP 7 V5.4 SP4 CPU314C-2DP V2.0.12 EATON SVX9000 DRIVE WITH PROFIBUS CARDS ET200S REMOTE IO My problem is now that I have reset the CPU to factory the program will not execute, I have done the following to try and resolve - I have loaded a blank config with just the OB1 in it -Verified it was empty by viewing online - Loaded a previously working version to the CPU - Viewed this online to confirm that the program was there - monitored OB1 and the PLC isn't executing - The only block showing anykind of online monitoring is the OB1 ALL other FB's state that they are not being executed(obviously since OB1 not cycling nothing else in the program will) I'm pretty new to the S7-300 stuff so I think that I'm missing something obvious here. Is there a setting in the CPU after reseting to factory? Is there a mystery function block that I am missing Should I upgrade the Firmware to V2.6.6 (Don't have the PG to do this) Is the MMC bad? Because you told us, that you are new to the S7-300 stuff I like to ask you: Is the mode switch in "RUN" position?
IBN-Service Posts: 8946 Rating: (999)
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1/5/2009 9:59 PM	Rate (0)
kwl Posts: 3 Rating: (0)	Yes the switch is in the RUN position. When I say new I have only had S7 experience with this CPU. my experience lies with ABB/Bailey/AllenBradley. Ihave done a 2 phase project on this one CPU, started in 2007 and the first phase went fine. phase 2 was this year and everything was going fine with commissioning until what I suspect is too many online changes. The CPU would fault when the third party drive was requested to start(EATON SVX 9000) . This is why I wanted to reset the 314 to factory and start fresh, to clean out any unwanted memory bits that where no longer used. Also to help others in the detective work, before the CPU faulted I was having trouble getting an M bit to change in the program, for example M11.0 was being toggled at network 1 on the FB and when you looked at the m11.0 further down in the same FB it was not changing, It was acting as if it was being overwritten by something, I checked all of the location that M11.0 was used and found no problems, even checked to see if an MW was overlapping and rewriting the bit but this wasn't the case either. Thanks Ken Lawrie Eco-Technica Engineering
kwl Posts: 3 Rating: (0)
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1/5/2009 10:37 PM	Rate (0)
FunStuff Posts: 103 Rating: (10)	How large is the program in work memory? The 314C only has 48kb of work memory.
FunStuff Posts: 103 Rating: (10)
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1/5/2009 10:46 PM	Rate (0)
IBN-Service Posts: 8946 Rating: (999)	kwl Yes the switch is in the RUN position. When I say new I have only had S7 experience with this CPU. my experience lies with ABB/Bailey/AllenBradley. Ihave done a 2 phase project on this one CPU, started in 2007 and the first phase went fine. phase 2 was this year and everything was going fine with commissioning until what I suspect is too many online changes. The CPU would fault when the third party drive was requested to start(EATON SVX 9000) . This is why I wanted to reset the 314 to factory and start fresh, to clean out any unwanted memory bits that where no longer used. Also to help others in the detective work, before the CPU faulted I was having trouble getting an M bit to change in the program, for example M11.0 was being toggled at network 1 on the FB and when you looked at the m11.0 further down in the same FB it was not changing, It was acting as if it was being overwritten by something, I checked all of the location that M11.0 was used and found no problems, even checked to see if an MW was overlapping and rewriting the bit but this wasn't the case either. Thanks Ken Lawrie Eco-Technica Engineering Hello Ken, is the green run LED on? The yellow STOP - LED must not be on or flashing. If it is green, the OB1 should be executed (green "RUN" - lineon the S7-Manager screenis pulsating). If not, may be there is some trouble with the PLC.... Otherwise: If the green RUN - LED is OFF and / or the yellow STOP LED is on / flashing, than the PLC switches itselfto STOP mode by any reason. i.e. the new drive is not connected properly to the Profibus (wrong adress, wrong GSD-File, wrong connection...?) In this case, the PLC goes to STOP, depending from the programmed alert - OBs (OB82 ff). Detailed information of the STOP - reason you will find in the PLC Diagnostic. The funny thing with the M11.0: In 2007, there was an very buggy Firmware. I dont know anymore ... if it was the Version V2.0 or V2.5.... Anyhow, this Firmware shows badly failfunctions if a block was watched online! Siemens immediatly release an update of the Firmware, witch you can use (since V2.5...?) even without MMC! If your Firmware is the buggy one (please check at the Simatic FAQ), you should update the FW asap. Good look!
IBN-Service Posts: 8946 Rating: (999)
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1/5/2009 10:49 PM	Rate (0)
IBN-Service Posts: 8946 Rating: (999)	FunStuff How large is the program in work memory? The 314C only has 48kb of work memory. The 314C-2DP got 96kB work memory since nearly2007.
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1/6/2009 1:28 AM	Rate (0)
kwl Posts: 3 Rating: (0)	Gents, thanks for your assistance sometimes just writing things down helps to troubleshoot the problem. I have found the problem with the OB1, in the original program my enable bits for the DB blocks that I call in my OB1 was in my first function block FB1 and this worked fine until I reset the PLC to factory default. I had to move my enable bits and first scan bits to the OB1 configuration so that the program would execute. I find this quite strange that the congiuration worked with the true and false toggled bits andfirst scan bits in FB1, then when the PLC was reset they had to be moved to be executed in OB1. Since resetting the PLC I have had no issues with the bit m11.0 or any other bits not reacting to changes in the logic. So far so good and commissioning continues in to the wee hours. Night all Thanks again
kwl Posts: 3 Rating: (0)
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1/6/2009 7:29 AM	Rate (0)
IBN-Service Posts: 8946 Rating: (999)	kwl I had to move my enable bits and first scan bits to the OB1 configuration so that the program would execute..... Also, you can use the OB100 for your enable bits, the OB100 will be executed any time when the plc starts. Enjoy, Jürgen.
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