Description of tag parameters is shown below.
- Name: is used for naming the data represented by the tag
- Device: identifies the device the tag is associated with
- Address: identifies the data area, as well as defines data type and dimension, and can affect the access rights. Address format depends on the specified device
- Update Rate: determines how frequently a tag is updated (in milliseconds). The 0 value indicates that the tag must not be updated (but it will be available for writing)
- Access: defines the access rights provided to the client (Read/Write or Read Only). Access rights can also depend on the specified address, for example: Internal Modbus registers always have read-only access rights. How to specify the read and write access rights of a tag for a specific user is described below
- Converter: specifies conversion applied to tag value. The following conversions are available: division by a specified number, linear scaling, logical “NOT” (available only for the boolean data type)
- Comment: contains any custom text
- Change Trigger: specifies change notification mode
Most of the parameters described above are available as OPC UA items. More information about editing server object properties via OPC UA is described here.