Configuring Tags for Alarms

A tag must be configured to trigger alarms by setting the alarm state trigger thresholds and by enabling alarming.

Note

Tag alarms are enabled by default.

To configure a tag for alarms:

  1. Open the details form for the tag that you want to configure. You can do this from either the Data Sources or the Site Tags module as follows:
    • In the Data Sources module, locate the site and tag and click More Info to open the details form
    • In the Site Tags module, use the Find tool to locate and select the tag.
  2. Select the tag and open the Alarm tab.
  3. Click Edit and enter these alarm details:

    All tag types

    FieldDescription

    Enabled

    Select this checkbox to enable alarm triggering.

    Priority

    Set the alarm priority. This property can be used when you are creating alarm actions for this alarm.

    Logged

    Specify whether alarm states are logged for this tag. We recommend that you set this flag. Alarm states can be logged even if you do not enable the tag to trigger an alarm

    Analogue tag types

    If the tag data is scaled, use the scaled value in these fields rather than the raw value.

    FieldDescription

    High High

    High-high alarm limit

    High

    High alarm limit

    Low

    Low alarm limit

    Low Low

    Low-low alarm limit

    Deadband

    		Set the width of the deadband for analogue alarms. This is used to suppress alarms triggered by random noise.

    The deadband is applied both above and below the trigger value.

    When a deadband is set, the alarm triggers above the deadband and clears below the deadband.

    ROC Time (sec)

    Time in seconds over which a rate of change is calculated. This is used in conjunction with the next two fields to calculate rates of falling and rising values.

    An alarm is triggered if the rate of rise, or the rate of fall, exceeds the limits specified

    ROC Rise

    Amount of rise - used with the rate of change time to calculate the rate of rise

    ROC Fall

    Amount of fall - used with the rate of change time to calculate the rate of fall

    Digital tag types

    FieldDescription

    Normal

    Specify whether the normal (non-alarmed) state for the tag is 0 or 1

  4. Click Save to save your changes.