DNP3 File Transfer

Typical use cases include downloading disturbance record files from the RTU or uploading configuration files to update RTU settings.

Important notes

In a distributed WinCC OA project, files are always downloaded to and uploaded from the project directory where the DNP3 driver is running.

In a redundant WinCC OA project, file transfer can be executed on either the active or passive driver.

• To transfer files on Host 1, write to the _DriverCommon data point element of Host 1.
• To transfer files on Host 2, write to the _DriverCommon data point element of Host 2.

Example for driver number 1:

• Host 1: _Driver1.RPC.Request
• Host 2: _Driver1_2.RPC.Request

Local directory configuration

The root folder for local file storage is defined by the configuration entry:

[dnp3] ftRootDir (Default: <PROJ>/data/dnp3/)

• Outgoing files: [dnp3] ftOutSubDir (Default: empty)
• Incoming files: [dnp3] ftInSubDir (Default: empty)

The parameters remoteFile, remoteDir and fileName are interpreted relative to the configured remote base directory ([dnp3] ftRemoteDir).

Execution via JRPC 2.0

File transfer operations are executed by writing a JRPC 2.0 request to the driver RPC request data point element.

• Request: _Driver<n>.RPC.Request
• Response: _Driver<n>.RPC.Response

File transfer operations

1. Put File

Uploads a file from the local directory to the remote RTU.

Example:

{
  "jsonrpc": "2.0",
  "id": "123",
  "method": "dnp3_putFile",
  "params": {
    "connDp": "_dnp3_connection",
    "localFile": "config.cfg",
    "remoteFile": "config.cfg",
    "userName": "",
    "password": "",
    "permissions": 0,
    "activateConfig": true
  }
}            

Optional parameter:

• activateConfig = true applies the new configuration (Function Code 31).

Key parameters:

• id: Unique request identifier.
• connDp: Connection data point name.
• localFile: File name in the outgoing directory.
• remoteFile: Target file name on the RTU.
• userName: Optional user name.
• password: Optional password.
• permissions: File permissions.

2. Get File

Downloads a file from the remote RTU to the local directory.

Example:

{
  "jsonrpc": "2.0",
  "id": "124",
  "method": "dnp3_getFile",
  "params": {
    "connDp": "_dnp3_connection",
    "remoteFile": "disturbance.dat",
    "userName": "",
    "password": ""
  }
}            

3. Read Directory

Retrieves file information from the remote RTU.

Example:

{
  "jsonrpc": "2.0",
  "id": "125",
  "method": "dnp3_readDirectory",
  "params": {
    "connDp": "_dnp3_connection",
    "remoteDir": "",
    "userName": "",
    "password": ""
  }
}            

4. Delete File

Deletes a file from the remote RTU.

Example:

{
  "jsonrpc": "2.0",
  "id": "126",
  "method": "dnp3_deleteFile",
  "params": {
    "connDp": "_dnp3_connection",
    "authenticationKey": 0,
    "fileName": "FRA00001.cfg",
    "userName": "",
    "password": ""
  }
}            

Error handling

Responses are returned in JRPC 2.0 format on the response data point element.

• Success: status equals ok.
• Failure: the response contains error details.

Possible error codes:

• ParseError (-32700)
• InvalidRequest (-32600)
• MethodNotFound (-32601)
• InvalidParams (-32602)
• QueueOverflow (-32000)
• InvalidResponse (-32001)
• Timeout (-32002)