A way to reset all %Q when comes a certain variable.

Hello  everyone,

Concerning the topic. Hope I've expressed understandable.

In other words I'm looking for a way to implement a function which does a reset of all %Q within a particular PLC.

So, how to do that professionally?

Msorich

Hello Msorich,

in my opinion should you implement a tag at all your logic which switch your outputs.
Maybe similar like the system-tag "FirstScan" at a 1200/500.

I don't know enough about your reason why you want to do this.
That's the reason because I can give you another better answer.

regards
CaOd

CaOd

in my opinion should you implement a tag at all your logic which switch your outputs.
Maybe similar like the system-tag "FirstScan" at a 1200/500.

 Something tells me there's a more common way to realize that. Probably it's connected with OB's.

CaOd

I don't know enough about your reason why you want to do this.
That's the reason because I can give you another better answer.

A reason is safety. For example an external watchdog stopped watching for some reasons --->

 ---> All %Q are to be reset. That's the point.

Msorich

[snip] ...

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question to moderator split to: Grip that had been intended to encrease/decrease size of EDIT POST Window?

Hello Msorich,

an easy way is to use a mapping-block to write the outputs. Depending on the language (LAD, SCL, ...) you are using you can jump over the regular conditions and reset all outputs.

Regards,

Frink

Prof. Frink

Hello Msorich,

an easy way is to use a mapping-block to write the outputs. Depending on the language (LAD, SCL, ...) you are using you can jump over the regular conditions and reset all outputs.

Regards,

Frink

 Is there a reading about?

Piotr, how do you find my approach? I mean reset of all %Q e.g. for safety reasons.

Have you ever realized that in your practice?

Msorich

Msorich

A reason is safety. 

If you plan to use a regular PLC and its program to achieve this then it's not safety (as meant by regulations) anymore.

For this a F-PLC is needed or proper design with safety relays.

jacek d

 For this a F-PLC is needed or proper design with safety relays.

Jacek, of course! There is a few safety relays already implemented.

However, we have to consider another safety circuit as additional to excisting one.

Msorich