Configure Digital Points

Use an OPC UA Digital Point to map an item of data on an OPC UA server to a digital point in Geo SCADA Expert database. You do this when the item of data on the OPC UA server has a digital value, to enable Geo SCADA Expert to represent that data in the database.

You configure the properties of each digital point using fields on the OPC UA Digital Point Form. The configuration Form contains many fields, organized into tabs. Most of these tabs contain properties that are common to points on many drivers (see Tabs on Point Forms in the Geo SCADA Expert Guide to Advanced Drivers).

The Digital Point tab includes properties that are specific to OPC UA Digital Points.

Use the Digital Point tab to:

• Configure the Common Point Properties
• Configure the Queue Parameters
• Configure the Filter Settings
• Configure Confidence Polling
• Define the Format of a Digital Point’s Values
• Define the Number of Bits for a Digital Point

  The Number of Bits value should be 1 when the monitored item on the OPC server is a Boolean data type. A Number of Bits value greater than 1 should only be configured when the monitored item on the OPC server is an integer data type.

• Specify the Bit Offset value (see Configure Digital Point States)

  A point should only be configured as a multi-bit point if it represents a monitored item that has an integer data type on the OPC UA server. The maximum offset is determined by the 'size' of data type and the number of bits.

• Configure the Point States (see Configure Digital Point States)
• Define the Persistence Type
• Configure the Override properties (see Define whether a Digital Point can be Overridden)
• Configure the Trend properties (see Define a Digital Point’s Trend Settings).

With each digital point that is to operate as an output point (in order to control plant), you also have to enable and configure the properties on the Control tab. You also use the Control tab to:

• Specify the Type of Digital Data that is being Controlled.

With an output point, users with the relevant security permissions can use either the 'standard' Control pick action, or the Control VQT pick action to write point data to the OPC UA server. (The latter provides the ability to write additional properties (the Quality and/or Timestamp) to the OPC UA server.)