Accessing always ON bit in Simatic S7 safety blocks?

[Binaural]

Hi all,

I'm a bit confused. In the siemens manual "SIMATIC S7 Distributed Safety - Configuring and Programming" there is a section regarding using always on/off bits in a failsafe FB.

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Boolean Constants "0" and "1"
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If you require Boolean constants "0" and "1" in your safety program to assign parameters during block calls, you can access the "RLO0" and "RLO1" variables in the F-shared DB using fully qualified DB access ("F_GLOBDB".RLO0 or "F_GLOBDB".RLO1).​

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I have configured my automatic DBs and the DB F_GLOBDB exists, although I cannot open it to verify these bits exist (block is protected). I am trying to access this DB from a safe block. However, I still cannot access it and can't find any information on the internet anywhere regarding this problem. Does anyone have any advice? Cheers!​

 

[Bratt]

You have to use symbolic adressing to access the bits.

"F_GLOBDB".VKE0 = Always off
"F_GLOBDB".VKE1 = Always on

 

[Binaural]

You have to use symbolic adressing to access the bits.

"F_GLOBDB".VKE0 = Always off
"F_GLOBDB".VKE1 = Always on

Thanks Bratt, problem solved!