smokey88

multi-screen alarm check/deleting

10 posts in this topic

Hi All,

I have a requirement from a customer to acknowledge alarms from either of two  NS15 HMI's in the system. Can anyone provide info on how I may be able to acknowledge or delete alarms on one HMI which would also acknowledge or delete said alarm(s) on the second panel? 

Both of the HMI's are polling one controller for alarm status so I assume that each time an alarm is acknowledged or deleted it would have to alert the controller which would then send something to the second HMI to clear the alarms?

Any help is appreciated.

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Write the acknowledge bit to the PLC from either panel? I would think once acknowledged the alarm bit would be transferred to alarm history in each panel as it is reset in the PLC.

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Hi Bob, thanks for your reply. I may actually be displaying my alarms in the wrong way based on your reply.

There are around 60 alarm registers so I was actually using the alarms history at the top of each page to display the alarms and then relying on an operator to check and then delete the alarm to indicate acknowledgement. Would you recommend using an alarm/event display for each of the alarms then? I thought this approach would be unsuitable for this amount of alarms initially.

Thanks

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60 alarms are chicken feed for these - I have one job with over 500 alarms. Set up an alarm page and an alarm history page. When setting up the alarms tick 'delete when alarm/event is cancelled'. That way the alarm screen will only show current alarms and alarm history will show history. I also set alarm history page to show day/time occurred and time cancelled. I also enable and set the ring buffer for history to 1000 events - then they can scroll down and see what has happened. You will also need to enable the vertical scroll bar so that you can scroll down pages in alarm history.

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Okay that sounds like a plan. This may be a dumb question but is an alarm/event display required for each of the 60 alarms or is it possible to set a single display for any of the 60 alarms? My customer has provided a requirement: "a summary of the most recent alarms shall be displayed on all HMI screens" which is why i went down the route of using a history table on the master sheet. If I could assign a single alarm/event display to cover all alarms for acknowledgements then I could include an alarm history display alongside it to meet those requirements.

Thanks

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Also just to add Bob, my customer wants alarm to be out of alarm AND an acknowledgement from the operator so delete when alarm/event is cancelled would remove the alert even without an operator acknowledgement if i understand correctly?

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It will take the alarm out of the alarm page but it will remain in the alarm history page. Events are different to alarms - there is the provision to select event and that can be set up in an event screen as well - modified alarm history screen but separate. Events are never alarms. PM me your email address and I will send you a project incorporating all these things. Customers invariably come up with a lot of impossible crap to be honest.

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Hello again,

Unfortunately my customer is still insistent on receiving an acknowledgement at the controller for each individual alarm. I have read into using macros for doing this but I am completely lost at trying to get the memory address for an item in the alarm queue. 

Here is a simplification of what I want to achieve:

Alarm display monitors 60, bit packed registers, and if one goes into alarm it appears on the alarm display.

Now usually when you press on the alarm display to dismiss the alarm  it joins the alarm history list. At this point is it possible for me to send a value back to the controller which acknowledges the alarm for a given register? i.e. i need to tell the controller which register I am sending the acknowledgement back for. 

I know this must be possible but what I want to do in my macro is to say: "clear this alarm (register X) and write a value of Y back to this register so the controller knows which alarm I have just acknowledged". I just cant seem to find a way of accessing the register number in my macro for a monitored register.

I hope I have worded this correct.

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Why not give them an acknowledge button that writes back to the PLC? That is what I do. Some alarms will then self reset when they go away - others latch and have to be reset by a reset button on the screen.

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