TIA Portal Creating Alarms

[thewalkerist]

Hello,

As a person who is not that experienced in plcs i am new to a lot of things in this environment. Today my problem includes the alarms, more specifically alarmview. Now to get you guys up to speed i would like to show my alarm conditions and what happens when alarm goes off and how do i deal with the alarm.

Now in screenshot (900).png we see our alarm condition. If S1 and S2 de-energize when we are in any of these steps our Sensor_Alarm_Bit will be set.

In screenshot (901) we can see what happen happens when our Sensor_Alarm_Bit goes off. If we are in any of these steps when our alarm goes off i want my motor to be stopped and my latch to be set(dont focus too much on latch, its trial mechanism that i put up ).

In network 3 we see what happens when we acknowledge the alarm (continued in screenshot(902)). It returns the speed value to the value it was before.

Now let say one of our sensors are not seeing and we are in step_6. Sensor_Alarm_Bit will go off and our motor speed wil go to 0. And lets say i fixed the sensor so now its seeing so everything is right again. And i click the acknowledge button in my HMI screen and i will move my specified motor speed in Step_6 to my Motor. And lastly i will reset the Sensor_Alarm_Bit.

Now on to the problem i encountered. I created my Alarm_View and when Sensor_Alarm_Bit energizes my Alarm_View shows me the alarm but there is a problem with acknowledging the alarm. Inside the Alarm_View there is a button for acknowledging, but i cant create an event and set my acknowledge bit with this button.

I know i can create a button myself and use it for both acknowledging and setting my bit at the same time. I already do it in my alarm screen. BUT i cant do this in global screen. I want to be able to acknowledge the problem from my pop-up alarm screen and i cant do it with my alarm_view's button. Maybe i can do it with a comfort panel? Is there a way to get over this problem with a basic panel?

 

[JesperMP]

I havent read all your text. It is hard to grasp what you want to achieve and how you have done it.

Now on to the problem i encountered. I created my Alarm_View and when Sensor_Alarm_Bit energizes my Alarm_View shows me the alarm but there is a problem with acknowledging the alarm. Inside the Alarm_View there is a button for acknowledging, but i cant create an event and set my acknowledge bit with this button.

I know i can create a button myself and use it for both acknowledging and setting my bit at the same time. I already do it in my alarm screen. BUT i cant do this in global screen. I want to be able to acknowledge the problem from my pop-up alarm screen and i cant do it with my alarm_view's button. Maybe i can do it with a comfort panel? Is there a way to get over this problem with a basic panel?

If you want an acknowledge button in the global screen, then you must also have an alarm view in the global screen. As you have found out, the acknowledgealarm function needs to point to an alarm view.

I have an alarm banner instead of the pop-up alarm view. The banner just shows 1 alarm, the most recently unacknowledged alarm
The banner as well as the ack button is placed in a Template so it shows on all screens.
One reason to do it in this way is that I dislike have an alarm view that pops up in front of the current screen content. This gets annoying real fast.

In addition the alarm banner I have screen with a list of alarms where you can scroll and search etc.

 

[drbitboy]

I don't know enough to answer the question about the HMI, but the logic in those images presents a possible problem:

1. If an alarm condition is active (Network 1, S2_Weigher_PE is 0 or S1_Conv_PE is 0), then 1 will be the value of the sensor alarm bit (%M100.0) on exit from Network 1 on all scans as long as at least one of those _PE (photo-eye?) bits are 0. That is good.
2. On the first scan when the value of the sensor alarm bit, the motor speed was set to 0 (Network 2). That is also good.
3. On subsequent scans as long as at least one of the alarm conditions is active,
   1. The motor speed will remain 0,
   2. But 0 will not be written to the motor speed on Network 2,
      1. Because the write to the motor speed only occurs on a rising edge of the alarm bit on Network 2 (P_TRIG #ONS2), and we have already noted that the sensor alarm bit will always be 1 at Network 2 because of the alarm conditions driving the Set (latch) on Network 1.
   3. If the HMI acknowledges the alarm (Acknowledge %M8.3 is assigned a value of 1) during one of the steps 4-7, then on Network 3:
      1. The preset speed will be written to the motor speed value, which is kind of good,
      2. And the sensor alarm bit will be Reset to 0 on exit from Network 3,
         1. But will be Set to 1 again by Network 1 during the next scan,
            1. So the P_TRIG on Network 2 will not detect a rising edge, and will not write a 0 to the motor speed value, even though at least on alarm condition is active.
               1. And the Motor speed will remain non-zero, which may not be good during an alarm condition.

Maybe this is intentional, in which case the "Acknowledge" bit should be called "Alarm Override."

See these two links for best practice in fault handling:

• Seal-in Pattern
• State/Fault Pattern

 

[thewalkerist]

Maybe this is intentional, in which case the "Acknowledge" bit should be called "Alarm Override."
[/LIST]

It was kinda intentional but i didnt know it was called Alarm Override.