DeltaV V12 Alarm Descriptions enable more descriptive alarm information

 

Typically a control module, as defined by the S88 standard, would contain process information associated with a single process signal or control loop. In this case, the module’s description and a standard alarm type (High, High-High, etc.) will generally provide an acceptable level of detail in an alarm list as seen below; identifying the process signal and what is abnormal about it.

While this is highly adequate for simple one-signal analog control or monitor type control modules, additional descriptive information is desirable for discrete and custom-designed alarms. For example, if the same tank had a high level switch, application of the Change From Normal (CFN) alarm type would produce an alarm as shown below.  Note that it is the module’s description that conveys the most useful information, identifying the alarm’s source (Tank 101) and alarm condition (high level).

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 While thoughtful naming of modules can be adequate in many situations, consider the case where a module contains custom-specified alarms based on information from multiple process signals, like an SIS SIF module. In this case dependence on the module's description and an alarm type (which sets the alarm word and message format) is often inadequate, sometimes requiring additional modules whose sole purpose is to provide more descriptive alarm information to the operator. Beginning in version 12 of DeltaV, a new configuration feature allows optional entry of a unique description for each alarm assigned to a module.  When an alarm is given a description, it appears in place of the module description in the alarm list (and elsewhere) as shown in the example below.  If no alarm description is supplied, the module's description is presented as has always been the case.

  

 Alarm descriptions may be configured individually or by bulk edit, and be put into active service without requiring downloads to existing control modules. Alarm descriptions are fully supported throughout the DeltaV system; supported by Version Control Audit Trail (VCAT), and appearing in the alarm banner (information line), alarm lists, event journal, and Alarm Help. Alarm descriptions require no incremental DeltaV system licensing. For more information contact your local Emerson sales office or local business partner.