anyone have a description of class a,b, and c shutdowns?

used for engine control systems on generators and compressors? I cant seem to find anything on the internet explaining what each class represents.

thanks.

Generally there are normally warnings and shut downs. If you go to the Woodward web site and obtain some manuals for the easYgen controllers and Leo PC 1 software there are refences to alarm classes.
Some are hard shut downs, soft shut downs and warnings.

I've seen them in the oil & gas industry defined as:

Class A Shutdowns are never inhibited, and initiate a unit shutdown any time a Class A Shutdown occurs. All Class A Shutdowns must be cleared and reset before a start can be initiated. Class A Shutdowns include Plant ESDD (Emergency Shutdown and Depressure), Unit ESD Push Button, Fire Detection, and Gas Detection.

Class B Shutdowns are inhibited for a period of time after unit start is initiated. This allows the inhibited devices a specific time period to attain their acceptable levels. Pre-lube oil pressure, as an example, is inhibited for a period of time during the start sequence.

Class C Shutdowns are inhibited until specific process conditions “arm” the specific shutdown.

Hi All, Anybody know if this logic is defined in a standard? I've seen it in AMOT and Spartan control systems but am unsure if this is standardized or just a convention for how to handle sequence logic and when trips should be turned on.