Digital Alarms have the following properties:
Alarm Tag
The name of the alarm. The name needs to be unique to the cluster. Alarm Tag names need to adhere to the Tag name syntax. If the name is not unique or is not syntactically correct it may not be recognized. If you have many tags, use a naming convention (see Using structured tag names). This makes it easier to find and debug your tags.
Note: Where Cluster Name is left blank, the name needs to be unique to defined clusters.
Cluster Name
The name of the cluster that runs this alarm. If the Cluster Name is not set, then this alarm will run on defined clusters.
Alarm Name
The name of the physical device associated with the alarm. This property is optional, it is only used when details of the alarm are displayed on the screen or logged to a device.
Alarm Desc
The description of the alarm. This can include variable data. This property is optional, it is only used when details of the alarm are displayed on the screen or logged to a device.
Var Tag A/Var Tag B
The digital variables (tags) that trigger the alarm. You can configure digital alarms to activate based on the state of one or two digital variables.
If you only use one variable to trigger the alarm, use the Var Tag A field. For example:
|
Var Tag A |
RFP3_TOL |
When the state of the variable RFP3_TOL changes to ON (1), the alarm is triggered.
Alternatively, you can define the alarm to trigger when the state of the variable changes to OFF (0), by preceding the digital address with the logical operator NOT, for example:
|
Var Tag A |
NOT RFP3_TOL |
In this case, the alarm is triggered when the state of the variable MCOL304 changes to OFF (0).
You can also configure digital alarms to activate based on the state of two digital variables, for example:
|
Var Tag A |
RFP3_TOL |
|
Var Tag B |
NOT MCOL304 |
In this case, the alarm is triggered when the state of both variables changes to the active state: when the state of the variable RFP3_TOL changes to ON (1), and when the state of the variable MCOL304 changes to OFF (0).
Note: If you leave the Var Tag B property blank, only Var Tag A triggers the alarm.
Category
The alarm category number or label. This property is optional. If you do not specify a category, the alarm defaults to Category 0.
Delay (hh:mm:ss)
The alarm delay period.
A digital alarm becomes active when the state of the triggering condition remains true for the duration of the delay period. The active alarm has an ON time of when the state became true.
This property is optional. If you do not specify a delay period, the alarm is active as soon as it is triggered by the digital tag(s).
Note: The delay period needs to be entered in the format HH:MM:SS (Hours:Minutes:Seconds). The value needs to be between 0 seconds (00:00:00) and 24 hours (24:00:00).
Help
The name of the graphics page that displays when the AlarmHelp() function is called by a user-defined command. This property is optional. If you don’t specify a help page, no action occurs when the AlarmHelp() function is called.
Comment
Any useful comment.
Extended forms fields
The following fields are implemented with extended forms (press F2).
Privilege
The privilege necessary by an operator to acknowledge or disable the alarm.
Note: If you assign an acknowledgment privilege to an alarm, do not assign a privilege to the command(s) that acknowledge the alarm. If you assign a different privilege to the commands, an operator needs to have both privileges to acknowledge the command. More importantly, the area defined here may be ignored.
Area
The area
to which the alarm belongs. If an operator
does not have access to an area, the alarm is not visible on the
alarm display. For example, if you enter Area
1 here, operators need to have access to Area 1 (plus any
necessary privileges) to acknowledge or disable this alarm.
Note: The area and privilege fields defined here needs to be designed to work in conjunction. A privilege defined on a button (say) will ignore the alarm defined area.
Custom Filter1...Custom Filter8
A user-defined string for filtering active alarms (maximum 64 characters).
Used in a custom Cicode query function as search
criteria, the custom alarm
filter enables operators
to identify and display a subset of active alarms.
Notes:
Paging
A read/write property that indicates whether the alarm will be paged. When the value is 1 (TRUE) the alarm will be paged. The default value is 0 (FALSE). See Alarm Paging Properties. This property can be read using alarm tag browsing and read or modified when tag properties are enabled using the tag name "myCluster.myAlarm.paging".
Paging Group
A read only text string that indicates the paging group to which the alarm belongs. Maximum length is 80 characters. See your third-party paging system documentation for information on how to use this Paging Group string. This property can be read using alarm tag browsing or when tag properties are enabled read using the tagname "myCluster.myAlarm.paginggroup". For example, assign the value of PagingGroup to a variable:
myString = myCluster.Alarm_1.paginggroup
See Also