WingBlog

Up until the mid to late 1970s, alarms were an important tool used to enhance a process operator’s situation awareness.  The steps to provide the operator with a single alarm included:

1. Purchase and add a sensing switch to detect an alarm condition.
2. Run conduit and cable back to the control room.
3. Purchase an enunciator module to add to the control panel annunciation system.
4. Connect all of the components.

This was not a task to be taken lightly and you only did it for alarms that really meant something.  The physical space for adding the alarms was also very limited.  As a result, each new alarm was evaluated and justified.

With the advent of the computer based control systems with layered applications, every tag in the system is a software construct.  Alarms are now free.  Also, every tag in the system has the capability of twelve to sixteen alarms To compound the issue, the young engineer, working for the engineering consultant or controls manufacturer doing your current controls upgrade, wants to make sure you get “your money’s worth” and will turn them all on.