Emerson Exchange 365

Help Understanding Alarms in Event Chronicle

Hello, 

Can you please help me understand what the following mean?

ACT/ACK

INACT//ACk

ACT/UNACK

How can I tell when the alarm went active and when the alarm acknlowedge the alarm?

Thank you

• PHV Alarms

DCS Newbie

• 3 Feb 2015 4:13 PM
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6 Replies

• Steve Linehan

  

  • 3 Feb 2015 4:24 PM

  The part before the / lists the status of the alarm ACT or INACT. ACT is when the alarm is active. INACT is when the alarm condition is normal. The part after the / shows when the operator acknowledged the alarm. When it is acknowledged it will change from ACT/UNACK to ACT/ACK. If is was INACT/UNACK it will change to INACT/ACT.

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• DCS Newbie

  

  • 3 Feb 2015 4:38 PM

  In reply to Steve Linehan:

  Thank you,
  
  For example, in the picture above the first high alarm occurs at 10:48, so when did the operator acknowledge the alarm? It looks like the operator

  Acknowledge the alarm at 10:48, and went inactive at 12:32. Then a low alarm went active and unacknowledge at 12:46.

  I think I understand now.

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• DCS Newbie

  

  • 3 Feb 2015 4:40 PM

  In reply to Steve Linehan:

  Thanks,
  
  How do I read the time 10:48:46.183 AM? What does the 46.183 mean?

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• Steve Linehan

  

  • 3 Feb 2015 4:54 PM

  In reply to DCS Newbie:

  In the picture you attached the operator acknowledged a high alarm at 10:48:46, the alarm condition cleared at 12:23:10 meaning the process was normal. There is no record of when the alarm activated in your picture. There should be a record of ACT/UNACK unless it is auto-acknowledge (unlikely with a priority of High). Look for an earlier event when the status is ACT/UNACT. The next event is a unassociated low alarm going active at 12:48:45. (Same instrument but not tied in with first alarm). The .183 after the seconds is fractions of a second, never really looked into what this exacty means but books online should tell you exactly what it is.

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• lazy_engineer

  

  • 3 Feb 2015 4:55 PM

  In reply to DCS Newbie:

  At 12:46 PM - The low alarm (LO_ALM) went active.
  At 12:23 PM - The high alarm (HI_ALM) went inactive.
  At 10:48 AM - The high alarm (HI_ALM) was acknowledged.
  
  The image posted does not show when the high alarm went active. The "State" field will read "ACT/UNACK" when an alarm goes active, and, if it is still active when it is acknowledged, "State" will display "ACT/ACK".
  
  The "46.183" means 46.183 second - that is seconds to the thousandths place.

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• DCS Newbie

  

  • 3 Feb 2015 7:01 PM

  In reply to lazy_engineer:

  Thank you Steve and lazy_engineer for responding. Thank you

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