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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 the 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 datapoints

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 3
time_sync_interval_sec integer Time frame between Time Synchronization
requests in seconds
No 60

gi_interval_sec integer

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 (SWT) Yes


rwt integer Receive window (RWT) Yes


cot_size integer Cause of transmission (COT) size in bytes No 2 1 2
ip string Host IP address (ipv4) Yes


t1

integer Acknowledge timeout t1 (sec) No 15

t2 integer Connection ACKRSN clock t2 (sec) No 10

t3 integer Connection TESTFR clock t3 (sec) No 20

originator integer Provides a means for a controlling station to explicitly identify itself No 0 0 255
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 log is 0 signal will not be logged. If log is more than 0 signal will be logged

No 0

gi boolean Including/excluding (1 or 0) signal 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 identificator No


select_ms integer Time limit in milliseconds for command
execution. Command select 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

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 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 wcclite:
    /etc/init.d/iec104-­master stop
  • Step 2: After 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/iec104-­master.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
-r [ –raw ] Show raw telegram data
-f [ –frame ] Show frame data
­-e [ –redis ] Show redis message -R [ –readyfile ] Ready notification file