Hi there guys,

Sorry for the most basic of questions. I would like to simply add a switch to an HMI screen to turn on an output Q0.1 on my S7-1200. I would then like that output to in turn show on my screen.

(I can successfully connect to each machine from my PC using two network ports and then pull the network cable out and connect them together to test. My program compiles ok for the HMI and the PLC program is one simple branch with an input i0.1 connected to Q0.1)

Each time I try and get this to work, nothing happens. I think I am missing something very basic.

Is there anywhere I can find info on this? I am trying to learn the basics coming from a Schneider background.

Thanks for your help,

Dan B

Hello aqueousdan,

the way I see it the problem is how you use the in- and output.

Instead if trying to access the input and output by the process and HMI at the same time (HMI and process will interfere and reset/set each other) put the HMI tags in a DB (or you can also use "M", like "M0.1", if you want to use the tag table instead).

HMI Input tag (in DB) -------> PLC Network
Process Input (Sensor) ----> PLC Network ---> Process Output (Actor)

• in the PLC Network (only pseudo-code):

IF ("HMI Input tag"=1  OR "Process Input"=1) THEN
"Process Output" =1
ELSE
"Process Output" =0
END IF

If you use an instance DB you can configure them as "static" (or anything else other than "temp").
If you use a global DB you need to connect the input and output of the function block - you're safe when configuring both as "In/Out".

• in the HMI:

Connect the "DB.HMI input tag" to the switch. ("General > General > Process")

Result:

HMI Input tag (in DB) =1  ------> PLC Network
Process Input (Sensor) =0 ----> PLC Network ---> Process Output (Actor) =1

HMI Input tag (in DB) =1  ------> PLC Network
Process Input (Sensor) =1 ----> PLC Network ---> Process Output (Actor) =1

HMI Input tag (in DB) =0  ------> PLC Network
Process Input (Sensor) =1 ----> PLC Network ---> Process Output (Actor) =1

HMI Input tag (in DB) =0  ------> PLC Network
Process Input (Sensor) =0 ----> PLC Network ---> Process Output (Actor) =0

The above is just a crude example as I don't know what exactly you have as In/Output.

(Other Option:
If you have no "Process Input (Sensor)" tag and want to set "Process Output (Actor)" only by HMI command, you can go to "Property > Events" and use the system functions "SetBit (Process Output)" on "Switch ON" and the system functions "ResetBit (Process Output)" on "Switch OFF". This way you don't need a network in the PLC.)

I think I went too far into it there. What I mean is that I cant seem to even get the basics to work.

Say I use a 1Hz clock memory byte to flash an output.

    %M0.5                               %Q0.1
-----| |---------------------------------(  )------

 I don't know what to do next to make that flashing output flash an indicator or button on the HMI screen.

I've come into this a bit blind. I don't know what documents to look at to learn the basics of it all.

Thanks

Hello aquedousan,

no problem, I'll give you some links for some basic tutorials and useful info.

So, first here is how cou deal with your question:

Make an indicator flash:

• Drag a "Basic Object" into your screen (like a circle).
• Go to "Properties > Animations > Display" and double-click on "Add new Animation".
• Select "Appearance" in the new window and cklick ok.
• Choose a tag. It will only be read, not written.
  You can browse trough the DBs, PLC tag table or HMI tag table to select a tag. Click on the [...] Button. You'll find your Mx.y or Qx.y under "YourPLC >PLC tags > Default tag table".
  Select the tag and click on the green check mark.
• Select the type (for example "Range" for datatype Integer, "Multiple bits" for Word, Byte and "Single bit" for Bool)
• Click "<Add new>". (as often as you need)
• Choose a color for the different values of your tag. 

Make an button to set a value:

• Drag the "Button" element into your screen.
• Go to "Properties > Events" and select an event (for example "Click").
• Click on the down-arrow at the right side of "<Add function>".
• A list with different categories appears. If you don't know the name of a system function one way to find out is to browse for them here. If you know the Name of the function you can type it in directly. The most important ones for Starters are "SetBit", "ResetBit", "SetTag". Use the first two for Bool, the last for everything else that is a number.
• Choose the tag (like described in the above example).
• Enter the value.

Useful informations:

• THE MANUAL (WinCC Adcanced V13 SP1)
  https://support.industry.siemens.com/cs/ww/en/view/109091876/74461101323
  (If you don't know where too look, use the search function of the manual)
  https://support.industry.siemens.com/cs/ww/en/view/109091876/74027009547
  (--> the chapter that contains all about visualization)
• The BIG list I posted in the thread "WinCC Best Tutorial Books"
  (https://support.industry.siemens.com/tf/ww/en/posts/wincc-best-tutorial-books/153531/?page=0&pageSize=10)