Show your own user messages on the S7-1500 display and Web

As I could't find any description about the Program_Alarm system function in any of the online PDF manuals or FAQs, I would like to share what I have found so far.

You can use the function Program_Alarm, which you find under Extended Functions, Alarming to generate your own alarm messages, which will be visible on the built-in display, the built-in web page as well in a TIA HMI panel. Note that all the classic system functions for alarms known from S7-300/400 like ALARM_8 and ALARM_S doesn't work in S7-1500. Note, that this function only works for s7-1500 and NOT for S7-1200, so you won't find the instruction when working with the S7-1200, at least not at the moment (May 2013, TIA V12, S7-1200 firmware V3.0). Things might change when firmware 4.0 for S7-1200 is out.

You can combine the alarm text with up to 10 process values, which you can format as integer, fixed point number, text strings or use the values to select a text from thetext lists stored in the project.

You can find information about Program_Alarm in the online help (Press F1 when the Program_Alarm block is marked) in TIA Portal.

You need a block call for each alarm you want to make. You don't have to think about alarm numbers, they are all generated automatically without conflicts, even when copying programs between projects.

You set the alarm trigger bit on the boolean input: SIG. If you need to look at a analog value, add a compare function in front of it and/or a timer to set up a filter. You may define up to 10 proces values to show as part of the the alarm text, which you attach on the inputs SD_1 to SD_10. It can be almost all PLC types, including numbers, boolean and strings.

To define the alarm text, click on the Instance Data Block on top of the block call and select Properties. You might add additional lines under Additional alarm texts. Please note, on the S7-1511 (the only one I tested) only the Alarm text, Info Text and Additional Text 1 is displayed on the display and web.

To include the process values you attached to the block call in the Alarm text, you add the following to your Alarm text or additional alarm text: @<No. of associated value><Format>@.

Examples of adding associated values (taken from Online help):

@1%6d@: The value from associated value 1 is shown as a decimal number with a max. 6 digits.
@2%6f@: The value "5.4", for instance from associated value 2, is shown as a fixed number of points "5.4" (three leading blanks).
@2%2f@: The value "5.4", for instance from associated value 2, is shown as a fixed number of points "5.4" (if number of digits is too small then these are not cut off).
@1%t#Textbib1@: Associated value 1 is the index by which the text to be inserted is referenced in the Textbib1 text library.
@4%s@ Display a Text string you have defined on SD_4

See more info about setting up alarms in the online help under Programming the PLC - Configuring alarms - Creating and editing alarms (S7-1500).

When an alarm is active, an exclamation mark (!) is displayed in a yellow triangle on the display. You then To see any active alarms, both user defined and system, select the second icon Diagnostics with the arrows and click OK. Select Alarm Messages in the menu list. To see details about an alarm, click OK when the alarms is selected. To see new incoming alarms, you need to go back to the main page by pressing ESC and go in again.

More info about the display inSystem Manual, 01/2013, A5E03461182-01 (http://support.automation.siemens.com/WW/view/en/59191792/0/en) from page 141.

Hope this might help somebody else needing the information as I did.