14.5 IEC 60870-5-104 Master
IEC 60870-5-104 protocol (in short IEC 104) is a part of IEC Telecontrol Equipment and Systems Standard IEC 60870-5 that provides a communication profile for sending basic telecontrol messages between two systems in electrical engineering and power system automation. Telecontrol means transmitting supervisory data and data acquisition requests for controlling power transmission grids.
IEC 104 provides network access to IEC 60870-5-101 (in short IEC 101) using standard transport profiles. In simple terms, it delivers IEC 101 messages as application data (L7) over TCP, usually port 2404. IEC 104 enables communication between the control station and a substation via a standard TCP/IP network. The communication is based on the client-server model.
To set up TLS connection for both IEC104 Master and Slave, refer to sections Excel configuration and Certificates. All keys and certificates should be provided in the PEM format.
If no configuration is set up, IEC104 Master and Slave services are not started.
Configuring IEC 104 Master data points
To use IEC 60870-5-104 Master in WCC Lite, it has to be configured via an Excel configuration. This configuration contains two Excel sheets where parameters have to be filled in Devices and Signals.
IEC 60870-5-104 Master parameters for Devices tab
| Parameter |
Type |
Description |
Required |
Default value (when not specified) |
Range |
|
|
Min |
Max |
|||||
|
name |
string |
User-friendly name for a device |
Yes | |||
|
description |
string |
Description of a device |
No | |||
|
device_alias |
string |
Alphanumeric string to identify a device |
Yes | |||
| enable | boolean |
Enabling/disabling of a device |
No | 1 | 0 | 1 |
| protocol | string |
Protocol to be used |
Yes | IEC 60870-5-104 master | ||
| asdu_address | integer | Application Service Data Unit address | Yes | 0 | 65535 | |
| asdu_size | integer | Common address size in bytes | No | 2 | 1 | 2 |
| time_sync_interval_sec | integer | The time frame between Time Synchronization requests in seconds |
No | 60 | ||
| gi_interval_sec** | integer |
The time frame between General Interrogation requests in seconds. If 0 requests are disabled |
No | 300 |
|
|
| port | integer | TCP port | Yes | 0 | 65535 | |
| ioa_size | integer | Information object address (IOA) size in bytes | No | 3 | 1 | 3 |
| swt | integer | Send window (k) | Yes |
|||
| rwt | integer | Receive window (w) | Yes |
|||
| cot_size | integer | Cause of transmission (COT) size in bytes | No | 2 | 1 | 3 |
| host | string | Host IP address (ipv4) | Yes | |||
|
t1* |
integer | Acknowledge timeout t1 (sec) | No | 15 | 1 | 255 |
| t2* | integer | Connection ACKRSN clock t2 (sec) | No | 10 | 1 | 254 |
| t3* | integer | Connection TESTFR clock t3 (sec) | No | 20 | 1 |
172800
|
| originator | integer | Provides a means for a controlling station to explicitly identify itself | No | 0 | 0 | 255 |
* - t1, t2 and t3 parameters must meet the inequality: t2<t1<t3.
** if gi interval is > 0, the number determines how often the gi request is being sent, if gi interval is 0, gi request will only be sent after the communication initialization and if gi interval is < 0 a request will not be sent at all.
IEC 60870-5-104 Master parameters for Signals
| Parameter |
Type |
Description |
Required |
Default value (when not specified) |
Range |
|
|
Min |
Max |
|||||
|
signal_name |
string |
User-friendly signal name |
Yes | |||
|
device_alias |
string |
Alphanumeric string to identify a device |
Yes | |||
|
signal_alias |
string |
Unique alphanumeric name of the signal to be Yes used |
Yes | |||
|
source_device_alias |
string |
device_alias of a source device |
For commands | |||
|
source_signal_alias |
string |
signal_alias of a source signal |
For commands |
|||
| enable | boolean |
Enabling/disabling of an individual signal |
No | 1 | 0 | 1 |
|
log |
integer |
Allow signal to be logged. If the log is 0, the signal will not be logged. If the log is more than 0, the signal will be logged |
No | 0 | ||
| gi | boolean | Including/excluding (1 or 0) signals from General Interrogation | No | 0 | 0 | 1 |
| common_address | integer | Address of a destination device | Yes | |||
| function | integer | Function number | No | 0 | ||
| info_address | integer | Information object address | Yes | |||
| data_type | integer | ASDU type identifier | Yes |
1, 3, 5, 9, 11, 13, 21, 30, 31, 32, 34, 35, 36, 45, 46, 47, 48, 49, 50, 58, 59, 60, 61, 62, 63
|
||
| select_ms | integer | Time limit in milliseconds for command execution. Command selection has to be performed before execution if this parameter is specified. Direct command execution can be performed only if this field is left empty or set to zero. |
No | 0 | ||
| periodic_update_ms | integer | Signal value is published periodically according to the value set. | No | - | - | - |
| tag_job_todo | string | The device status signal can be configured by providing given value |
No |
No |
communication_status |
|
Device status signals
IEC 60870-5-104 has an additional signal which can be configured to show communication status. It indicates if the slave device has disconnected from the master (WCC Lite). To configure such signal for IEC 60870-5-104 protocol, tag_job_todo field with string value is required. For IEC 60870-5-104 master required parameters for the status signal will be: signal_name, device_alias, signal_alias, and tag_job_todo. Tag_job_todo must be: communication_status. If the signal returns the value of 1 – the device or protocol connection is on and working properly, if 2 – the device is off or the protocol is disconnected.
Debugging an IEC 60870-5-104 Master application
If the configuration for IEC 60870-5-104 devices is set up, the handler for the protocol will start automatically. If a configuration is missing parameters or contains errors, the protocol will not start. It is done intentionally to decrease unnecessary memory usage.
If IEC 60870-5-104 does not work properly (e.g. no communication between devices, data is corrupted, etc.), a user can launch a debug session from the command-line interface and find out why the link is not functioning properly or use WCC Utility to do that.
To launch a debugging session, a user should stop the iec104-master process and run the iec104-master command with respective flags.
- Step 1: Service must be stopped by entering the following command into the WCC Lite:
/etc/init.d/iec104-master stop - Step 2: After the service is stopped it must be started with the preferred configuration file (JSON
files found in /etc/ folder) and a debug level 7:iec104-master -c /etc/iec104-master/ttyPORT1.json -d7 - Step 3: Once the problem is diagnosed normal operations can be resumed with the following command:
/etc/init.d/iec104-master start
IEC 60870-5-104 command-line debugging options
-h [ –help ] Display help information
-V [ –version ] Show version
-d<debug level> Set debugging level
-c [ –config ] Config path
-e [ –redis ] Show redis message