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Entry type: FAQ Entry ID: 16644635, Entry date: 08/04/2003

Acknowledgment of faults does not work

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Why, after acknowledgment, isn’t a fault displayed correctly in the alarm line in PCS 7 AS?

An alarm message is displayed in the alarm line. A red flashing drive icon is displayed in the flow diagram. The operator acknowledges the alarm line, the alarm "disappears" from the alarm line, but the drive icon continues to flash red.

In the system chart (CFC) SYSPLCxx, on the "PLC" block is the counter output "OS_CNT" which counts the incoming WinCC messages. This counter does not change its value although acknowledgment of the alarm line should also trigger an acknowledgment message in the PCS 7 AS.

There are three requirements for acknowledging alarms:

1. Acknowledgment buttons
The acknowledgment buttons in the standard PDLs have to be added for a CEMAT project. You do this in the Graphics Designer via "Acknowledgment buttons > Object properties  > "Event" tab > Mouse click". Please refer here to our configuration manual, in the chapter entitled "Creating the PCS 7 Project", in the section entitled "Standard picture adjustments for the message system".

There are alarm acknowledgment buttons in a total of four pdl files:

  • @AlarmOneLine.pdl
  • @Buttons11.pdl
  • @Buttons12.pdl
  • @Buttons13.pdl

Here for the mouse click (Acknowledge Alarm/Horn) you must call the relevant functions that have the AS number in parentheses as parameter. The relevant line has to be available for each of the existing PCS 7 ASs.

Acknowledge Alarm(01) // Acknowledge AS No. 1
Acknowledge Alarm(02) // Acknowledge AS No. 2
Acknowledge Alarm(03) // Acknowledge AS No. 3

Please note that there are different C functions:

  • for multiclients, TH container names included in symbol
  • for multiclients, TH container names not included in symbol
  • for server/single-user stations, TH container names included in symbol
  • for server/single-user stations, TH container names not included in symbol

2. System CFC
When creating the project you have to copy a system CFC from the CEMAT library into each AS. The original CFC is called "SYSPLC00" and has to changed according to the AS No. in each case.

SYSPLC01 // for AS No. 1
SYSPLC02 // for AS No. 2
SYSPLC03 // for AS No. 3

3. Internal tags
The section entitled "Assigning parameters in Tag Management" in the configuration manual "Creating the PCS 7 Project" describes how you have to create two internal tags.

C_<Computer name>_AlarmSound

The first tag must always include the computer name. This tag is therefore different on each PC. 

Only when all three points are set correctly does acknowledgment also work in the PCS 7 AS.

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