Emerson Exchange 365

Alarm Question/Plant Horn

We presently alarm through a PA system.  What is the preferred method to make this redundant?  One workstation's speaker output goes to the PA amp.  When this computer goes down (i.e. operate not running), alarm is inaudible.  I was thinking I could simply wire speaker output from two workstations to PA, but then our intermittent alarms would be garbled (I believe the WAV files don't play syncronously with one another on different workstations when alarm sounds?)  -- I was thinking I could just use a schedule to toggle a parameter, and have second computer detect this and enable/disable its horn?  How is this typically handled?  I have different sounds configured for warning, critical, LEL alarms.

Frank Seipel

• 21 Oct 2012 1:09 AM
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5 Replies

• Steve Elves

  

  • 21 Oct 2012 3:24 AM

  I worked on a project 3 years ago where there was a requirement to annunciate alarms over a radio system.  The customer specified a device called a “Protalker”, which had the ability to broadcast up to 31 different pre-recorded messages, either to a PA system or over a radio.  The particular message to be sent was driven by a set of 5 DI’s, which we wired to a DeltaV DO card.  Logic in the controller monitored alarms by Plant Area, and sent a particular code so that field operators would hear something like “Critical Alarm in Steam Plant Area” as a recorded message.

   

  I don’t recall where the customer bought this device, but I would wager you could find it on Google.  Since the broadcast logic was done in a controller, it was independent of any one workstation.  Perhaps this kind of device would work for you.

   

  Steve Elves

   

   

  

   

  Steve Elves | Control Systems Tech.

   

  From: Frank Seipel [mailto:bounce-FSeipel@community.emerson.com]
  Sent: Saturday, October 20, 2012 6:10 PM
  To: DeltaV@community.emerson.com
  Subject: [EE365 DeltaV Track] Alarm Question/Plant Horn

   

  We presently alarm through a PA system.  What is the preferred method to make this redundant?  One workstation's speaker output goes to the PA amp.  When this computer goes down (i.e. operate not running), alarm is inaudible.  I was thinking I could simply wire speaker output from two workstations to PA, but then our intermittent alarms would be garbled (I believe the WAV files don't play syncronously with one another on different workstations when alarm sounds?)  -- I was thinking I could just use a schedule to toggle a parameter, and have second computer detect this and enable/disable its horn?  How is this typically handled?  I have different sounds configured for warning, critical, LEL alarms.

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• Dewey Kuchle

  

  • 22 Oct 2012 5:24 PM

  In reply to Steve Elves:

  I think Steve is on the right track here.  I've used the ProTalk devices from Barnett Engineering in the past with good success.   They've been around for a long time and I haven't used one recently but I remember these being pretty simple devices that we triggered with DO's to send out an audible message by telephone or PA.    Looks like they've got a new one now with a cell phone embedded that will do email and SMS as well as telephone and PA.   Have a look here and see what you think   www.barnett-engg.com/index.aspx

  rgds,

  dewey

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• Bill Sayers

  

  • 24 Oct 2012 2:41 AM

  In reply to Steve Elves:

  Is it possible to monitor alarms in an Area to fire a DO? I know you can see how many alarms are active and suppressed in a Area but I was thinking of a way to turn on an output just in that Area.

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• Frank Seipel

  

  • 24 Oct 2012 2:52 PM

  
  

  Yes, you should be able to set up an event to trigger on AREA_A/ALARMS[1].F_NALM=1 for instance, to set a module parameter to 1 with frswritevalue; this input parameter can then be wired to the DO.

  
  

  When value goes to zero it would write the parameter to zero.

  
  

  See http://www3.emersonprocess.com/Systems/Support/bol113/extfile/b_theory/html/alarm_horn_parameter.htm

  
  

  Alternately, you can do this entirely in a module, by creating a calc block that polls each module's alarm state & fires the DO.  It would be nice if the controllers made these arrays available to modules but that doesn't appear to be the case?
  

  
  

  -Frank
  

  
  

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• Youssef.El-Bahtimy

  

  • 24 Oct 2012 4:54 PM

  Frank, I was going to suggest the same thing. You can read the area/almcnt in watchit so presumably a control module can read it.... however in watchit it only populated the value if the workstation and user filtering allowed it. So if no one is logged in, then it won't fire from operate, and it is doubtful the controller can resolve it.
  
  Frank Seipel <bounce-FSeipel@community.emerson.com> wrote:
  
  

  
  

  Yes, you should be able to set up an event to trigger on AREA_A/ALARMS[1].F_NALM=1 for instance, to set a module parameter to 1 with frswritevalue; this input parameter can then be wired to the DO.

  
  

  When value goes to zero it would write the parameter to zero.

  
  

  See http://www3.emersonprocess.com/Systems/Support/bol113/extfile/b_theory/html/alarm_horn_parameter.htm

  
  

  Alternately, you can do this entirely in a module, by creating a calc block that polls each module's alarm state & fires the DO.  It would be nice if the controllers made these arrays available to modules but that doesn't appear to be the case?
  

  
  

  -Frank
  

  
  

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