We would like to control access to shelving of alarms, preventing shelving for some and only allowing certain users to shelve others. I appreciate that shelving is controlled by which lock the field .OPSUP is assigned to. The obvious solution is to give users access to the key for this lock only in certain areas and then assign the alarms which they can suppress to this area. However we already have a complicated area system for access to different plants. Is there another way?
I found that if the suppression timer limit is set to 0 then the alarm cannot be shelved (or at least it is shelved then immediately unshelved). This would prevent shelving entirely but wouldn't allow differentiation between users.
I'm wondering if you could benefit from one of the AgileOps applicatinos like List Management
This gives you independent levels of control for alarm management rather than attempting to configure the DCS logic.
There is also the Dynamic Alarm Management module that can implement State based alarming
As for handling this in DeltaV, you could create a module that manages suppression, abstracting out the alarms that can or cannot be suppressed. A module can write to the OPSUP and SUMTMO fields of another module. This would allow all modules to remain in their current plant areas, but give you a new module you could place in a new Plant Area and restrict access to it, and remove access to OPSUP in all other areas. This could get complicated really fast, so I don't know if this is viable. Just a thought.
Maybe you could add some signature policies that require confirmation in order to suppress certain alarms. If OPSUP requires a supervisor and only some Operators have that privilege, maybe that lets you control who can suppress and who cannot.
Personally, I like the idea of the AgileOps Alarm management layer. This allows you to separate alarm management functions from control module logic. The people managing alarms can implement strategies that do not require control module changes and downloads. It provides a clean break in responsibilities. Although Alarms are appropriately executed in the controller where they are time stamped and are universally reported to all consoles from one source, the suppression and operator management of alarms makes more sense to be managed above the controllers.
Andre Dicaire
In reply to MPHymel:
Here is a pic of the detail alarm tab mentioned above
In reply to Andre Dicaire:
In reply to Cedric Dawnhawk: