S7-200 SM31.7 problem

ghulamshoaib

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• Jan 30, 2023

• #1

Hello

S7-200 CPU 224 CN is installed and SM31.7 is used for data write to EEPROM

Now I have uploaded the program from CPU 224CN and downloaded it to CPU 224 standard

problem is that when I set SM31.7 then it does not go back to 0 state and remains ON

what may be the reason?

waiting

 

chud

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• Jan 31, 2023

• #2

if it does what its supposed to do why not just use a pulse timer and switch it off

 

chud

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• Jan 31, 2023

• #3

I take back what i said after reading this

 

ghulamshoaib

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• Jan 31, 2023

• #4

Hello
According to the manual, SM31.7 goes to zero automatically after writing values
In Old cpu 224 cn , this function is working properly. When I set it, it becomes 0 automatically
But in cpu 224, it is not working. When i set it to 1, it remains 1
Please suggest solution
Thanks

 

ghulamshoaib

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• Feb 1, 2023

• #5

anyone here who can help?

 

moggie

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• Feb 2, 2023

• #6

ghulamshoaib said:

anyone here who can help?

Click to expand...

Can you post a screen shot of the PLC program that controls SM31.7 ?

 

ghulamshoaib

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• Feb 2, 2023

• #7

please find the attached picture

there are many networks in which SM31.7 is being used

 

moggie

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• Feb 2, 2023

• #8

So it looks ok - I would suggest you go online and check each network where SM31.7 occurs to see if eg. M18.5 / M18.6 / V2000.4 etc are being "re-triggered" in the program?

 

ghulamshoaib

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• Feb 2, 2023

• #9

M18.5 M18.6 etc are triggered from hmi
So there is no chance of being triggered inside plc
Moreover, same plc program works fine with old cpu 224 cn

 

moggie

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• Feb 2, 2023

• #10

Have you been online and checked?
What is the status of SM0.0
What is the value in SMW22
Failing this then the save function has not "finished" - (maybe a corrupt EEProm ? DB)?

 

ghulamshoaib

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• Feb 2, 2023

• #11

I will check the status of SM0.0 and value of SMW22
so if it seems that the issue is due to some corrupt EEPROM then what is the solution?