With the modern DCS, documenting alarms on P&IDs may be more trouble than it is worth.
DCS Alarm Configuration
Some reasons to consider:
Bad PV Alarms - With the advent of better instrumentation, every analog transmitter seems to be capable of generating a “Bad PV” diagnostic alarm. These certainly don’t add value to the P&ID, so why include any alarms at all?
Alarm names are differen t – Alarm names on P&IDs (e.g., TAH100 and TAHH100) are often different than those used in the DCS (e.g., TIC100-High and TIC100-HighHigh).
Alarm rationalization defines the alarms to be configured in the DCS - Alarm rationalization is the process of reviewing potential alarms to verify that they meet the criteria for being an alarm, and for documenting their cause, consequence, corrective action, priority, and limit. The output of rationalization is a master alarm database (MADB), which is the authorized list of rationalized ala
rms and their settings. Since rationalization is an ongoing activity, much effort would be spent updating the P&IDs to keep them consistent with the MADB.