DNP3 Driver

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The DNP3 protocol is designed to avoid real time data loss even in the event of communication failure. The DNP3 protocol does this by storing point value changes with a timestamp in the Outstation. When communication is lost, the Outstation continues to record events in its event buffer. When communication is restored, the Outstation sends the stored events to Fernhill SCADA. Fernhill SCADA uses the stored events to fill in the data that was missed while the communication link was down.

The Fernhill SCADA DNP3 driver supports these communication options:

SerialDNP3 over point to point and point to multi-point serial links

Fernhill SCADA DNP3 Tags

The DNP3 driver provides these tag types to support communication with DNP3 Outstations:

IconTag TypeVersionDescription
Channel IconDNP3 TCP/IP Channel Tag3.46An IP Address used for DNP3 TCP/IP communication.
Channel IconDNP3 Serial Channel Tag3.46A serial port used for DNP3 serial communications.
PLC TagDNP3 Outstation Tag3.46A DNP3 Outstation.

To configure Fernhill SCADA to communicate with a DNP3 outstation do the following:

  1. Create and configure one of the following channel tags depending on your communication requirements:
  2. Create a DNP3 Outstation Tag. Set the Channel property of the DNP3 Outstation Tag to the channel tag you created in step 1.
  3. Create I/O Data Point Tags to represent the points in the DNP3 Outstation. For each I/O Data Point Tag you create:

You can monitor the status of the tags in the Tag Status Window.

Fernhill SCADA I/O Data Point Tags

You can use these I/O Data Point Tags to represent individual data points in the Outstation:

IconTag TypeVersionDescription
Analog Data Point TagI/O Analog Data Point Tag3.12Maps an Analog Data Point Tag to an external data source.
Digital Data Point TagI/O Digital Data Point Tag3.12Maps a Digital Data Point Tag to an external data source.
String Data Point TagI/O String Data Point Tag3.12Maps a String Data Point Tag to an external data source.
Word Data Point TagI/O Word Data Point Tag3.12Maps a 16-bit Word Data Point Tag to an external data source.
Double Word Data Point TagI/O Double Word Data Point Tag3.12Maps a 32-bit Double Word Data Point Tag to an external data source.
Long Word Data Point TagI/O Long Word Data Point Tag3.48Maps a 64-bit Long Word Data Point Tag to an external data source.

DNP3 Object Flags and Data Point Tag Quality

DNP3 Outstations send data to the Master Station using DNP3 Objects. A DNP3 Object defines exactly how data should be encoded.

Some DNP3 Objects include Object Flags that provide additional quality indications about the data source. When Fernhill SCADA receives a DNP3 ObjectswithObject Flags, the following logic is used to set data point tag quality:

When Fernhill SCADA receives a DNP3 ObjectswithoutObject Flags, the data point tag quality will be GOOD (192).

Further Information

DNP3 Point Address Format

To learn how to choose a data location in a DNP3 Outstation.

Serial Communications

For background information on serial communications.

Fernhill SCADA Drivers

For information about other drivers available in Fernhill SCADA.


For the meaning of terms used in Fernhill SCADA.