Shelve and unshelve alarms at runtime

Operators can shelve alarms to temporarily suppress them for a fixed period. Shelving an alarm means temporarily removing it from the Alarm Control’s main alarm list and placing it on a shelved list. Shelving is normally controlled by an operator to handle irrelevant nuisance alarms that have not been caught by filtering or alarm suppression mechanisms.

When shelving an alarm from the Alarm Control, operators set an associated time period in which the alarm remains shelved and enter a mandatory comment. Operators can select from a list of Alarm Control Context commands during run time to:

• Shelve one or more selected alarms

• Shelve all alarms

• Shelve only those alarms visible in the Alarm Control

• Shelve all alarms within the same alarm group as an alarm selected from the Alarm Control

• Shelve alarms by selected tags or attributes

• Shelve alarms by selected alarm priorities

• Shelve all alarms that have the same severity as an alarm selected from the Alarm Control

When application security is used, alarms can be shelved and unshelved only by operators with proper authorization. For more information about setting shelving authorization, see Configure the Alarm Control to require a SHELVE signature.

Shelved alarms are automatically unshelved at the end of the specified time period.Operators can also manually unshelve alarms and return them to an active state. Alarms are unshelved automatically at the end of the shelving time period. An unshelved alarm reappears in the Alarm Control active list and resumes its state at the time it was shelved. Operators can manually unshelve a shelved alarm before the end of the shelved period and enter an optional comment.