OB123 ?

AN is instruction in STL Language of programming..

Write in cyclic interrupt OBs.

They are from OB30.

 Ah yes, I had just cyclic instead of cyclic interrupt. I now have the instructions in an OB30 block. However, it still says unknown instruction and tag not defined, interestingly the program compiled fine with no errors?

I have attached a picture again.

Thanks

PSW2586

OB123 ?

AN is instruction in STL Language of programming..

Write in cyclic interrupt OBs.

They are from OB30.

 ah right I see! This is great thanks for helping guys! I have set up the ladder diagram as shown in the attached image. When you say set up the interrupt OB, I think I have done that by selecting cyclic interrupt, is that what you mean?

In terms of the functionality of this just so I understand it properly. We set it to cyclic interrupt at a time say 100ms. So every 100ms, if Q64.7 is false it will put activate Q64.7 for 100ms and will it then reset until the next cycle? so that every 100ms Q64.7 will be true? and finally, does the signal stay true for a period of 100ms?

Thanks again guys

William_B

PSW2586

OB123 ?

AN is instruction in STL Language of programming..

Write in cyclic interrupt OBs.

They are from OB30.

Hey,

I forgot for a moment that you do not have STL on the S7-1200.
In the forum we sometimes go to STL or SCL as it types easier here.

..sorry..

What you'll do is the LAD equivalent:

      Q64.7           Q64.7
------| / |-----------(  )

Do make sure you have the interrupt OB set right.

(thanks to PSW2586 efforts on this!)

w

William_B

gimmetheloot

 ah right I see! This is great thanks for helping guys! I have set up the ladder diagram as shown in the attached image. When you say set up the interrupt OB, I think I have done that by selecting cyclic interrupt, is that what you mean?

In terms of the functionality of this just so I understand it properly. We set it to cyclic interrupt at a time say 100ms. So every 100ms, if Q64.7 is false it will put activate Q64.7 for 100ms and will it then reset until the next cycle? so that every 100ms Q64.7 will be true? and finally, does the signal stay true for a period of 100ms?

Thanks again guys

I call this a "heartbeat" signal. And you understand it now.

Now what do you do on the other end?..
You will have to monitor it.
Let us say you decide to measure for x5 slower.
That means if you have a TRUE or a FALSE for 500ms or longer,
then there is a problem.

Does it make sense?
w

 Yes it makes sense now thank you so much!