A High-High Alarm will generate an alarm when the value of the tag is above the Alarm Limit. The tag will remain in High-High alarm until it is acknowledged and the tag’s value drops below the HH alarm limit minus deadband.
The Alarm Limit is set during configuration of the tag, but can be changed in run-time VIEW while on-line from the point detail display if the user has access to the Security Level 127 configured for Tag Fields. The alarm Limit can also be changed by appending the .ALMHH to the tagname in the Point Info Dialog Box (point Browser).
The relevant fields to consider when
configuring a High-High Alarm are the
Hi Hi Priority, the HH Alarm Limit, the Deadband, and the Span High and Span Low of the Tag.
To configure a High-High alarm see 7.4Alarm Configuration.
1. Enter a non-zero Alarm Priority by clicking on the field in the field labeled Hi Hi Priority. This is an abbreviation for High-High Alarm Priority.
If you are using a High Alarm also, then the High-High Alarm Priority must be greater than or equal to the High Alarm priority.
2. Enter a numeric value for the Alarm Limit. The alarm limit is in engineering Units.
If you are using the High Alarm also, then the High-High Alarm Limit must be greater than the High Alarm Limit.
3. Log Only - Specifies that Alarms are written to the Alarm Log only. No notification of alarms is made on displays or alarm summary or email or pager for this tag. This can be specified individually for each alarm type, for analog tags.
If Alarm Log to ODBC is specified for the SCADA Node and Log Data for this tag, Alarm will be written to the central Analog Tag Log on the Project Node.
4. Send Email - Specifies if this tag will generate an Email when it alarms. An Alarm Email Server must be configured for the SCADA node. Alarms must be enabled. Email To for the SCADA Node or Email To for this tag must also be configured.
5. Email to - Adds another name to the Email To field for the SCADA node. If the SCADA Node Property - Email To is blank, then this is the only person(s) to receive the Alarm email.
6. Play Voice - Specifies if Text-to-Speech Annunciation of the Alarm will be used. The Voice selected in Alarm Voice in SCADA Node Properties will be used. The voice will try to pronounce the tagname, alarm type, description, alarm limit and value triggering the alarm will be read. The Tag Name will be spelled out if it is not a word. For example, “Compressor” will be announced, but “compressor1” will be spelled out: “see oh em pee are ee ess ess oh are one.”