The Alarm Priority drop-down list enables you to select the priority of the alarm that will be triggered for this tag. The available priorities are:

•    0 – Event

•    1 – Critical Alarm

•    2 – High Alarm

•    3 – Warning Alarm

•    4 – Notice Alarm

If you have defined your own alarm priority tags, those will also be available for selection.

The Alarm State spin box enables you to select the trigger for the alarm.  The alarm will be triggered when the tag's state becomes one of the following:

•    0    The alarm is triggered when Bit 0 goes low. The bit 1 address either has not been provided or is low.

•    1    The alarm is triggered when Bit 0 goes high. The bit 1 address either has not been provided or is low.

•    2    Two addresses provided. Bit 0 goes low and Bit 1 goes high.

•    3    Two addresses provided. Both Bit 0 and Bit 1 go high.

•    Upon Change  - any change of state triggers an alarm.  Note that when the Upon Change option is selected, the trip alarm option will be set and cannot be un-selected by the developer.

Transient changes in state can result in multiple alarms being triggered.  By setting an alarm delay, you can specify that if the tag’s state changes back one which does not constitute an alarm situation, it must remain in that state for a given length of time before the alarm is deemed to be inactive. 

The Disable Alarm checkbox enables you to specify whether the low alarm for this tag is disabled or enabled. Disabling of alarms is typically used in situations where you wish to avoid false alarms. For example, in the event that routine maintenance is being performed on the equipment represented by this tag, or when you are aware that another interruption in communications will occur for a period of time; in such situations, the alarm can be disabled until the maintenance is complete and communications are reestablished.

The Trip Alarm checkbox enables you to indicate whether you wish this alarm to be a trip alarm. A trip alarm occurs and remains active when value of the alarm tag changes from a 0 to a 1.

When the Append State to Alarm Message checkbox is selected, VTS will append the text used for the state of the tag, as taken from the Off Text and On Text fields in the tag’s I/O tab, to the alarm message.

If the configuration variable AlarmPopupsEnable is set to 1, then setting either the Low Alarm Popup Enable or the High Alarm Popup Enable, will result in a pop-up dialog being displayed whenever the respective alarm is triggered.  It is strongly suggested that this feature be used sparingly.

Note: If you wish to override the built-in alarm for a pump status tag, please refer to Overriding Built-in Alarms.