Book Contents

Options on the Triggers tab of the Alarm Setup editor

The following table shows the options on the Triggers tab of the Alarm Setup editor.

Options

Descriptions

Select trigger

Select a trigger from the list.

Add...

Click this button to add a trigger.

Edit...

Click this button to edit a trigger.

Remove

Click this button to remove a trigger.

Trigger settings

Specify trigger properties in this area.

Trigger type

Select the type of data the trigger’s tag or expression uses:

  • Value - integer or floating point values. Floating point values are rounded to the nearest integer. Use with analog or digital tags.
  • Bit - a bit array consisting of one or more bit positions. Use this trigger type to generate multiple alarm messages with a single tag (or array tag) or expression. Each bit in the array whose value changes from 0 to 1 triggers an alarm if a message is configured for the bit.
  • LSBit (least significant bit) - an analog or digital tag, or a direct reference bit array consisting of one or more bit positions. Use this trigger type to trigger alarms based on a priority sequence that is determined by bit position. When multiple bits in the array change from 0 to 1, only the alarm with the lowest bit position is triggered. The LSB trigger type property does not work with tags that use the Default data type. Default data type is Floating Point, and LSB does not support Floating Point.

    Bit and LSB trigger types can be used with a digital HMI tag or a direct reference using the array syntax.

Trigger label

Type a label for the trigger, up to 40 characters long. Do not use commas.

The alarm list and alarm status list use these labels to filter the alarms shown in the list.

You can configure the alarm status list to show trigger labels.

Use ack all value

Select this check box to send a value to the data source when the operator presses the Ack All (Acknowledge All Alarms) button or when a RemoteAckAll connection occurs.

In the box, type the integer value to send.

Optional trigger connections

Specify the following optional trigger connections:

  • Handshake - a write connection. Assign a digital tag to this connection to notify the data source when the trigger connection’s value changes.
  • Ack - a write connection. Assign a digital or analog tag to this connection to notify the data source when an alarm is acknowledged by the operator.
  • Remote Ack - a read connection. Assign an analog tag or an expression to this connection to allow the data source to acknowledge alarms.
  • Remote Ack Handshake - a write connection. Assign a digital tag to this connection to notify the data source when a remote acknowledgment occurs.
  • Message - a write connection. Assign a tag to this connection. When the alarm is triggered, if the Message to Tag option is selected on the Messages tab, up to 82 characters of the message text is written to this connection. The maximum string length supported is 82 characters. Make sure the tag supports the type of data sent in the alarm message.
  • Message Notification - a read/write connection. Assign a digital tag to this connection if you want to use message handshaking. This connection notifies the operator that an alarm message has been sent.
  • Message Handshake - a read connection. Assign a digital or analog tag or an expression to this connection. This connection provides the run-time terminal with confirmation that alarm messages are received by the data source.

    Do not configure an alarm’s Trigger and Remote Ack settings to use the same tag. Doing so may cause unpredictable alarm acknowledgement behaviors.

Name

This column shows the name of the connection.

Tag or expression

Type the tag name or expression associated with the connection. If a tag or expression was selected, it is shown here.

Tag button (...)

Click this button to open the Tag Browser and select a tag instead of typing the tag name in the Tag or expression column.

Exprn button (...)

Click this button to open the Expression Editor and create an expression instead of typing the expression in the Tag or expression column.

See also

The Triggers tab of the Alarm Setup editor

Create an alarm trigger

Edit an alarm trigger

How values are rounded

All properties