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rajCNC

Error OBs

7 posts in this topic

Dear All,

Please anyone help me to understand. 

I am very new to Schneider platform, i am working with Siemens platform .

* Please let me know there is any provision to add error OBs like, OB121,OB122 in siemens.

 

Thanks&Regards,  

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I Also dont know Siemens. What is an OB?

 

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OB is operation block.

Schneider don't speak about DB, FC and OB.  Schneider speak about EF - elementar functions, DFB - derivate function blocks and data

I think  OB Siemens = DFB Schneider

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Sounds like a function or function block to me.

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Posted (edited)

Hi,

OB means organization Block, it can't be compared with Schneider DFB. OB121 and OB122 are specials organization blocks that can be used to avoid to stop the processor when a programming error occurs (OB121) or I.O error (OB122). So don't look at this on Schneider Plcs, they don't exist so you don't need it :)

JC

 

Edited by acpi

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Posted (edited)

use online help and search for %S and %SW - by using system bits /words you can setup if the PLC should stop

Edited by Quant

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You're right, some Schneider plcs system bits could be used to "emulate" some OB, but in this particular case it's not really interesting. With a Siemens Step7 Plc, if you address a memory area that doesn't exist, your plc will stop. If you add OB121 (that is not present by default when you create your project) it will not. It's really a totally different philosophy between Siemens and Schneider and it's not a good idea to try to do with a Schneider plc what you did with a Siemens.

JC

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