These column headings are displayed for a Filtered String Value Map:
- Address—The unique identifier for the entry within the Value Map. The address is allocated automatically when you Specify the Map Size.
- Object—The name of the item. This information is inherited from the variable, point, or other type of value when you associate it with the Value Map.
- Change Detection Type—Filtered Value Maps can store alarms and events for the slave device, to indicate string changes. Use this column to specify whether the Filtered String Value Map is to store any such alarms or events for each mapped value. Choose from:
- None—The default option. The Filtered Value Map does not store any alarms or events that the source generates as a result of a change in string value.
- Event on Change—The Filtered Value Map stores any events that the source generates as a result of the string changing value.
- Alarm on Keyword—The Filtered Value Map generates an alarm whenever the string includes the trigger phrase specified in the Alarm Trigger Phrase column (see below).
- Alarm Trigger Phrase—Only used when the Change Detection Type (see above) is set to Alarm on Keyword. Enter the phrase that may be included in the string that is retrieved for this entry. Whenever the string includes this phrase, the Filtered Value Map creates an alarm entry for this change.
- Class—The type of data that the slave reports to its master has to be assigned a class. The class is used at the master to assess which type of data to retrieve from the slave. For example, on DNP3, Class 0 specifies static data (present values and states).
Each Class row within a Filtered Value map is automatically assigned as Class 0 when a variable, point, or other value is allocated to that row. Alter from the default if a different class is required.