First Project with S7-1200 TIA V16

No.

Bullzi said:

Is it considered "Best Practice" to create a FB to map the physical I/O to DB tags? I will normally do this in the AB world. Just not sure how it is done in the Siemens world.

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In ControlLogix there is the particular 'feature' that the IO is scanned asyncronously with the scan, causing all kinds of problems. Programmers deal with this by copying all i/o to/from a buffer and work with the buffer instead of the actual i/o. Siemens do not have this feature and thus you dont have to use a buffer.


If you still do not want to work directly with the i/o, then embrace the use of FBs. You pass the physical i/o to the FB by means of In/Out pins. Inside the FB you work with the variables assigned to the in/out pins.

The big deal is that in this way your code is re-used every time you create an instance of the FB.

Thanks Jasper, that makes sense.
What I have done is to create a UDT called Tank. In the Tank UDT I have a couple of items that will actually interface with the I/O. Items like Mixer_Status and Mixer_Run. The Mixer_Status I want to be connected to a Input that comes from the Motor Aux contact and the Mixer_Run I want to be connected to a Output that will be wired into the Motor Starter Coil. So I was trying to figure out how to connect DB tag to the Physical I/O.
Am I making any sense here? I have been using AB for about 20 years and suddenly I feel like a beginner ever since I have been trying to learn Siemens. I kind of feel like it would be easier to learn Siemens if I had no experience at all with PLC's.

Is there more than 1 tank to process?

Yes there are 5.

Bullzi said:

Is it considered "Best Practice" to create a FB to map the physical I/O to DB tags? I will normally do this in the AB world. Just not sure how it is done in the Siemens world.
Thanks!!

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I do this all the time but I use an FC as I do not need any persistent data.
I use the FC to very easily make changes and specially to OR inputs and outputs (in separate FCs) for testing and simulating.

I do consider it very good practice.

And my view on best practice is that it is individual.

I learn what is considered best practice, look at other people's code, try it out and decide if it works for me.

If one way appeals to my brain and how I process things then that's the best way; specially for writing code, my eyes/brain like to see things organized in a certain way and feels more intuitive then that's best practice for me.


And to your point about learning Siemens, I suggest you take your time and not to do it perfectly Siemens, whatever that is, focus on the task and learn along the way; unless the object is to learn Siemens.

Example tank program using a UDT and some I/O

asdf

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Electrical data

Pulse versionPulse “Low Power” version12 - 36 V DC, filtered and regulated12 - 36 V DC filtered and regulated (via Bürkert transmitter)

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Thanks LD.



The boss just sent me this spaghetti diagram of additions the customer wants us to make and we're almost done building the panel . Please make the necessary changes and send a list of the any additional hardware we need to squeeze in this already crowded pane.



Much appreciated.

Thanks LD,
I got some very valuable "tips" from your example. I appreciate the time you have taken to help me during this post!!