Alford, who is a retired engineering advisor (Process God) at Eli Lilly, started by talking about automobile alarms.
In the industrial plant situation:
- large #of configured alarms
- many nuisance alarms
- cost of configuring a new alarm is essentially free
- situation getting worse with indreasing numbers of smart field devices
- minimal creation of "intelligent" alarms
- little data mining pursued to extract information and knowledge content of data
- multiple process steps, phases
- many transients
- process loads, setpoints = f(time) little if any steady state operation
- desire to sort and query alarm records by lot number, step, phase, etc.
- desire to visualize data via "relative time" rather than calendar time
- adhere to definition of alarms: i.e., an alert to "abnormal situations requiring a response."
- Tag alarm records with sufficient information needed for display, sorts, queries, and report generation...including lot number, categor, priorit, process step/phase
- generate more intelligent alarms-- make use of all available relevant information (e.g. "if-then" rules incorporating redundant sensors, trend slopes, other correlated variables)
- eliminate nuisance alarms
- do not include 'notifications' on alarm displays
- use unique colors in displaying alarms (if red is used to display high priority alarms, avoid red for other info on console)
- minimize multiple alarms per "abnormal" event
- ensure that alarms ALERT, INFORM, and GUIDE
- records easy to access and understand-- non crypitc
- sufficient alarm tag information to accommodate expected queries, sorts and batch reports: e.g., lot number, category, process step and phase
- displayable in relative time
- utilities to include Pareto chart (alarm frequency) and other alarm metrics: e.g., alarms per day
- ability to combine discrete and continuous trend data to facilitate abnormal event analysis
- abilityto use of PCA, PLS, neural nets., etc. in developing virtual sensors and or identifying a small number of key independent variables that are predictive of important process outputs.
- separates equipment from process
- encourages sequential flow diagrams
- identifies process states
- connect alarms to the enterprise