How can you troubleshoot DCS alarms and alerts?

Troubleshooting Distributed Control System (DCS) alarms and alerts is a critical aspect of maintaining the integrity and functionality of an industrial process. Here are steps you can take to effectively troubleshoot DCS alarms and alerts: Acknowledge Alarms Investigate the Cause Check Instrumentation Review Control Strategies Operator Error Process Upsets Collaborate Historical Data Testing and Validation Documentation Root Cause Analysis Review and Audit Remember that effective troubleshooting of DCS alarms and alerts is an ongoing process. It requires a combination of technical knowledge, experience, and a proactive approach to maintain the safety and efficiency of industrial processes. Additionally, complying with industry standards.

The best thing is always follow rules for Alarm rationization .ISA 18.2 Set deadband and on delay times to minimise nuisance alarms generation. Alarm generation should be 4-5 alarms per hours for continuous plant in normal operating condition. For batch process set condtional alarms etc... Differentiate alarms by priority. Remove unwanted/repeated alarms with the help of proper MOC system This is intial step which will make troubleshooting process very easy.

Alarms can also be grouped in terms of criticality to the overall function. That is , safety or process alarms with different colour pop ups..... this will assist engineering personnel to establish steps in resolving the alarms.....

Alarm management is part of a DCS Engineer job, alarms should be continually optimized... For example, eliminating unnecessary alarms that do nothing than confuse the operators...

Never ignore an alarm ! Always be sure to verify the alarm through logic before you chose to ignore or shelf it; especially in case of recurring alarms.

DCS alarm and alert troubleshooting should be identify real process alarm or fault due to failure. The most difficult alarm is intermitted or frequent alarm are hard to identify where the alarm is sources. After identified the alarms, root cause of alarm sources which mean it affect by communication or physical failure.Process Instrumentation failure may identify using TSLD and simulation devices such as HART , current sources devices and modbus simulator to identified source of alarms. All the Input devices and Final Control elements are alarm clear, Finding the wiring loops test to find source of error. Sometimes alarms comes from JBs which water ingress and point error.

Sometimes, alarm status can be categorized as long standing alarms that cannot be reset, due to specific conditions such as the value of normal process conditions is greater than the value of startup process conditions and operation teams wants to keep the set point of alarms in startup condition, because of any recommendations from the licensors. In this case, maintenance, alarm management and operation team shall coordinate and discuss on how to act with these kind of alarms. The resolve or action is case-by-case for each alarms

(1) Segregate the alarm by type like diagnostics, process alarms, critical limits exceed alarms etc. (2) Implement alarm rationalization techniques based on alarm philosophy document.

1-type of alarm(A:system,B:process) 2-find the where came from(marshlling or system cabinet),the tag and location 3-fix the wiring or field instrument.

Its good to have alarm management team who reviewing all alarm on DCS in timely basis, while single process/instrument alarm will be capture by DCS operator / technician in day to day operation then follow up with work order, but some times standing alarm even bad actor alarm required extra effort to be follow up, this action may go up to MOC process or procedure revalidation. Even COP update may required to adjust the condition change.

I categorize Alarms mainly into three categories: 1) Process Alarms (Trip HH, High/Pre-Trip High, Low/Pre-Trip Low, LL/Trip LL) 2) Instrument Failure (Loose Wire, Short Circuit, Instrument fail, Fuse blown) 3) Control Failure (Card Fail, Channel Fail, Controller Fail, Logic issues, Power Supply Issues, Network Switch/Cable fail, Workstation fail etc. Some Engineers combine type 2 and 3 into hardware failure or I&C failure that's understandable. Alarms Rationalization and Alarm help make the Alarms management System effective and help avoiding unforseen shutdown or at least rectifying at earliest.

DCS alarms management is something which must be having action party allocation based on the type of alarms and their criticality. There are process alarms which normally require operator attention. Some field instrumentation diagnostic alarms need to be addressed by maintenance professionals. While system alarms need intervention of DCS or system engineers.

Operator action is required for sure even though Trip has occurred for Mobilizing any of below: - Emergency Response - Field Operators - Maintenance Team to rectify Trip cause so plant can be started at earliest or at least save the unit. Also for Diagnosing spurious/bad actor alarms for shelving purposes or instruct instrument team to rectify it Trip alarm is also required to alert operators incase Trip is Overriden/Bypassed. Many more reasons are there!

HH or Trip is not an alarm. That is the event category. If any alarm doesn't require operator action that doesn't fall in the alarm category.