Operator Confirmation/Acknowledge bit evaluation in PLC
Created by: KayBee at: 7/15/2009 9:36 AM (6 Replies)
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| 7/15/2009 9:36 AM | |
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Posts: 241 Rating:
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Hi, Dear Experts, Here I need a litle help. I am using SFC17 , ALARM_SQ & SFC18 ,ALARM_S to send alarm to PC RT & MP377. Now I have some message that needs operator confirmation to be evaluated in PLC,that is when operator read the message & confirm by pressing a button on HMI, the PLC will get a "confirmation bit"to start some other job.I have many such messages that need to be selected one by one and must be confirmed by operator.How I can implement in Wincc Flexible 2007, our PLC is S7 317-2dp. I checked the HMI button function but it didn't set any bit in PLC. Thanks. |
| 7/15/2009 1:00 PM | |
Joined: 3/18/2009 Last visit: 12/6/2024 Posts: 306 Rating:
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There is no direct status output from SFC17 and 18. So no direct bit. The "Q_State" output should tell you whether a paricular SFC17 (basically a particular EV_ID) has been acknowledged or not. Hope it helps.
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| 7/18/2009 2:43 PM | |
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Posts: 107 Rating:
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Hi ! You can try the following - You have already declared discrete alarms which is connected to a tag and and some bit numer from this tag. If you go to the Colum headers in the discrete alarms page you should also see a header called HMI ack tag and HMI ack bit.If you are not able to see this option go to the header with mouse pointer, right click , you will see the option and select it. Create a tag with word type and in the alarm use this tag as HMI ack tag with some valid bit number. In the alarm view ->properties->display->select ACK and ensure buttonbar style stays at buttons. With this whenever an alarm is selected on the alarm view and acknowledged with the ACK button the corresponding bit in the HMI ack tag will be set in the PLC and you can read the same. I have tested this with Runtime simulator and it works - just be careful about the byte swap |
| 7/20/2009 2:32 AM | |
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Posts: 241 Rating:
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Thanks Bhaskaran, I have checked that, it's fine solution if we need only one Button 'ack'. Here my Client's requirement changed mean time. Now Requirement is TWO acknowledged buttons. One is 'OK' & another is 'Cancel'. If operator press OK, PLC will do some action according to that and if s/he press ' Cancel' PLC will do other actions.I am still searching the option in PLC as well as HMI, if it is possible.. Any clue? |
| 7/20/2009 1:25 PM | |
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Joined: 3/18/2009 Last visit: 12/6/2024 Posts: 306 Rating:
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This is what I understand of your requirement: Let's say you get a message Alarm1. You want two buttons Btn1 and Btn2. Btn1 will acknowledge Alarm1 and perform "ActionA" Btn2 will acknowledge Alarm1 and perform "ActionB" Is my understanding correct? You can achieve the above by 1. Create one binary "Flag". 2. On Btn1 write the script to set the Flag (use SetTagWait) and Acknowledge the message. 3. On Btn2 write the script to reset the Flag (again use wait) and Acknowledge the message. 4. In PLC using SFC17, find out if a message is being Acknowledged. Based on this and the status of the Flag bit, trigger either ActionA or ActionB. (Use triggers, i.e. rising edge of message acknowledgement bit) You only need one flag bit per PLC for all your messages. hopefully this helps. |
| 7/20/2009 1:56 PM | |
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Posts: 241 Rating:
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Thank you daga, I will check this. We are using WinCC flexible, I am not sure if the Script Instruction you have mentioned is available or not . |
| 7/20/2009 3:19 PM | |
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Joined: 3/18/2009 Last visit: 12/6/2024 Posts: 306 Rating:
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oops..i forgot you were using Fles.. But I am sure there must be an equivalent to set/reset a bit in WinCC Flex. regards.
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