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Problem with redundant CPU: LED flashing

Created by: Aporo at: 10/8/2014 10:29 AM (4 Replies)

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10/8/2014 10:29 AM	Rate (0)
Aporo Posts: 2 Rating: (0)	Dear all, I have a problem with the redundant CPU. As you can see in the below image all LED are flashing. Moreover, when I force this problem for 1st time I try to restart the CPU. Then the problem solved. But 1 after 5 days CPU has the same problem. Please help if you know, Thank you Attachment PLC_CPU_IM.jpg (458 Downloads)
Aporo Posts: 2 Rating: (0)	Last edited by: Min_Moderator at: 10/8/2014 1:09 PM New subject after splitting from /tf/WW/en/Posts/115019#top Last edited by: Aporo at: 10/8/2014 10:36 AM
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10/8/2014 10:45 AM	Rate (0)
Marcjan Platinum Expert Joined: 4/22/2010 Last visit: 10/17/2024 Posts: 5697 Rating: (715)	Hello, First thing to do is go online and check Diagnostic buffer, you can save the diagnostic as a textfile and attach it to your post. regards, Marcjan
	Problem solved? Please let us know! Please no technical questions by PM, use the forum sections for your questions.
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10/9/2014 3:53 PM	Rate (0)
Aporo Posts: 2 Rating: (0)	Dear Mr Macjan Here is the Diagnostic Buffer of CPU. Yhank you again, Apostolos Attachment Diagnistic Buffer.zip (436 Downloads)
Aporo Posts: 2 Rating: (0)	Last edited by: Min_Moderator at: 10/13/2014 10:41 AM Attached the Diagnistic Buffer
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10/10/2014 11:32 AM	Rate (2)
zahra hatampour Posts: 15 Rating: (3)	hello based on diagnostic buffer the OB72, OB82 and OB86 are called and did not existe in program or disabled by SFC 39 DIS-ITR. at first you should add these OB's to your program to prevent from cpu stop. I rewrite here the exact reasons of calling these OB's written in "System Software for S7-300/400 System and Standard Functions Volume 1/2" : 1-The operating system of the H CPU calls OB72 when one of the following events occurs: • Loss of CPU redundancy • Reserve-master switchover • Synchronization error • Error in a SYNC module • Updating aborted • Comparison error (for example, RAM, PIQ) 2-If a module with diagnostic capability for which you have enabled the diagnostic interrupt detects an error, it outputs a request for a diagnostic interrupt to the CPU (when entering and outgoing event). The operating system then calls OB82. The local variables of OB82 contain the logical base address as well as four bytes of diagnostic data of the defective module (see the following table). 3-The operating system of the CPU calls OB86 whenever the failure of a central expansion rack (not with S7-300), a DP master system, or a station is detected in the distributed I/Os (PROFIBUS DP or PROFINET IO) (both when entering and outgoing event). If OB86 has not been programmed, the CPU changes to the STOP mode when this type of error is detected. each OB has some outputs which leads you what happend for example if OB82 called as a result of hardware failure in a DI, the address and type of I/O carts specified in OB82 outputs.I suggest you study pages 1-25, 1-34 and 1-45 of above mentioned document about ob72,82 and 86 which is accessible in internet . it seems that you have lost a DP slave (with address 7) and an I/O module in rack 0 related to the master CPU and befor that CPU Switched from master to standby in event 80 (I do not know why, check ob72 data ) and lost redundancy and went to solo mode in event 79. as it did not call ob 70 you did not have I/O redundancy problem . I think more information about I/O redundancy and OB 'S data is required to decide what realy happend
zahra hatampour Posts: 15 Rating: (3)
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This contribution was helpful to 2 thankful Users hdhosseini Marcjan

10/21/2014 9:23 AM	Rate (0)
JoseV. Posts: 6 Rating: (0)	I had the same problem once and it was beacuse of some bad conection on the profibus conectors on the Y-links I had...
JoseV. Posts: 6 Rating: (0)
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