Skip to main content

29.1 IEC 60870-5-101

The IEC 60870-­5-­101 protocol is a companion standard for power system monitoring, control associated communications for telecontrol, teleprotection, and associated telecommunications for electric power systems. Standard IEC 60870­5­101 was prepared by IEC technical committee 57 (Power system control and associated communications).

Standard IEC 60870-­5-­101 defines an Application Service Data Unit (ASDU Figure below). In ASDU there is ASDU identifier(with type of ASDU in it) and information objects.image-1638258623652.png

IEC 60870­-5-­101 ASDU structure

Common Address of ASDU Defines the stations address and can be configured in Devices asdu_address field for source and Signals common_address field for destination.

Information Object Address Used as destination object address in the control direction and as source object address in monitor direction can be configured in Signals info_address field.

Standard IEC 60870­-5­-101 transmission frames are separated into 3 different types: frame with variable length, frame with fixed length and single control characters

image-1638259001158.png

IEC 60870­-5-­101 ASDU structure

Control field provides information about the message direction, type of service and checksum.

Address field specifies the link address which points to the messages destination. WCC Lite supports IEC 60870-­5-­101 Master protocol over serial link (according EIA RS­485). Its full functionality list can be found in a IEC 60870­-5-­101 PID Interoperability List which can be downloaded separately from this user manual.

Configuring datapoints (master)

To use IEC 60870-­5-­101 Master in WCC Lite, it has to configured via an Excel configuration. This configuration contains two Excel sheets where parameters have to be filled in ­Devices and Signals.

IEC 60870-­5-­101 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 60870­-5-101 master
device

string

Communication port

Yes

 

PORT1

PORT2

baudrate integer

Communication speed, baud/s

No

9600

300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200

databits integer

Data bit count for communication

No

8

6

9

stopbits integer

Stop bit count for communication

No

1

1

2

parity

string

Communication parity option

No

none

none, even, odd

 

flowcontrol

string

Number of requests, before link is considered lost (device status signals are changed) and reconnect attempt will be issued

No

none

none

 

link_address integer Destination address when in transmit and source address when broadcasting Yes   0 65535
link_size integer Link address size in bytes No 1 1 2
asdu_address integer Application Service Data Unit address Yes   0 65535
asdu_size integer Common address size in bytes No 1 1 3
ioa_size integer Information object address (IOA) size in bytes No 2 1 3
cot_size integer Cause of transmission (COT) size in bytes No 1 1 2
time_sync_interval_sec integer Defines how often (in seconds) slave will
request time synchronization. If greater than 0 ­slave will request synchronizations, will reset timer if master did it earlier. If 0 slave won’t request timesyncs, but will allow them. If ­1 ­ timesyncs are not supported ­ requests will be dropped.
No 60    
gi_interval_sec integer Time frame between General Interrogation requests in seconds, if 0 requests are disabled No 300

 

 

scan_rate_ms integer

Polling interval in milliseconds. Time frame between two telegrams from master

No 100    
timeout_ms integer

Response timeout in milliseconds

No

1000

 

 

retry_count integer

Number of retries of failed requests before announcing that device is in Error state

No 1    
IEC 60870­-5-­101 master parameters for Signals tab
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      
info_address integer Information object address Yes      
data_type integer ASDU type identificator Yes      

IEC 60870-­5-­101 has an additional signal which can be configured to show communication status. It is used to indicate if the slave device has disconnected from master (WCC Lite). To configure such signal, two columns should be filled with particular values. To a newly created additional signal one should make job_todo equal to device_status and tag_job_todo equal to communication_status.

Debugging a IEC 60870-­5­-101 Master application

If configuration for IEC 60870-­5-­101 devices is set up, handler for protocol will start automatically. If the configuration is missing or contains errors, protocol will not start. It is done intentionally decrease unnecessary memory usage.

If IEC 60870-­5-­101 does not work properly (e.g. no communication between devices, data is corrupted, etc.), a user can launch a debug session from command line interface and find out why link is not functioning properly. To launch a debugging session, a user should stop iec101­-master process and run iec101-­master command with respective flags as shown in the table below.

Procedure for IEC 60870-­5-­101 master service debugging:

  • Step 1: Service must be stopped by entering the following command into the wcclite:
    /etc/init.d/iec101-­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: iec101-­master -­c /etc/iec101-master/iec101­master.json ­-d7
    Additional output forming options described here: Command line arguments.
  • Step 3: Once the problem is diagnosed normal operations can be resumed with the following
    command: /etc/init.d/iec101-­master start
IEC 60870-­5­-101 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
-R [ –readyfile ] Ready notification file

Configuring datapoints (slave)

To use IEC 60870­-5­-101 Slave in WCC Lite, it has to configured via an Excel configuration. This configuration contains two Excel sheets where parameters have to be filled in ­Devices and Signals.

IEC 60870-­5-­101 slave 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 60870­-5-101 slave
device

string

Communication port

Yes

 

PORT1

PORT2

baudrate integer

Communication speed, baud/s

No

9600

300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200

databits integer

Data bit count for communication

No

8

6

9

stopbits integer

Stop bit count for communication

No

1

1

2

parity

string

Communication parity option

No

none

none, even, odd

flowcontrol

string

Number of requests, before link is considered lost (device status signals are changed) and reconnect attempt will be issued

No

none

none

 

link_address integer Destination address when in transmit and source address when broadcasting Yes   0 65535
link_size integer Link address size in bytes No 1 1 2
asdu_size integer Common address size in bytes No 1 1 3
ioa_size integer Information object address (IOA) size in bytes No 2 1 3
cot_size integer Cause of transmission (COT) size in bytes No 1 1 2
time_sync boolean Allow time synchronization, 1 to enable and 0 to disable No 0 0 1
sp_time boolean Add CP56Time2a information to single point signals, 1 to enable and 0 to disable No 0 0 1
dp_time boolean Add CP56Time2a information to double point signals, 1 to enable and 0 to disable No 0 0 1
me_time boolean Add CP56Time2a information to measurements, 1 to enable and 0 to disable No 0 0 1
message_size integer Maximum length of a message Yes   0 255
cache_size integer Maximum number of events to store in a buffer No 100 0 1000
respond_delay integer Time in microseconds to wait before sending responses Yes   0 1000000
single_byte_ack boolean Use single character acknowledge, 1 to enable and 0 to disable

No

0 0 1
keep_alive_timeout integer Time interval in seconds before serial
connection is considered offline

No

60    

keep_alive_timeout timer is used for connection tracker to display protocol status. This parameter has no effect on protocol functionality and is only used to track it’s status in connection tracker.

IEC 60870­-5-­101 slave parameters for Signals tab
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      
info_address integer Information object address Yes      
data_type integer ASDU type identificator Yes      

IEC 60870­5­101 has an additional signal which can be configured to show communication status. It is used to indicate if the slave device has disconnected from master (WCC Lite). To configure such signal, two columns should be filled with particular values. To a newly created additional signal one should make job_todo equal to device_status and tag_job_todo equal to communication_status.

Debugging a IEC 60870­5­101 Master application

If configuration for IEC 60870-­5-­101 devices is set up, handler for protocol will start automatically. If the configuration is missing or contains errors, protocol will not start. It is done intentionally decrease unnecessary memory usage.

If IEC 60870-­5-­101 does not work properly (e.g. no communication between devices, data is corrupted, etc.), a user can launch a debug session from command line interface and find out why link is not functioning properly. To launch a debugging session, a user should stop iec101­-slave process and run iec101-­slave command with respective flags as shown in the table below.

Procedure for IEC 60870-­5-­101 slave service debugging:

  • Step 1: Service must be stopped by entering the following command into the wcclite:
    /etc/init.d/iec101-­slave 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: iec101-­slave-­c /etc/iec101-slave/iec101slave.json ­-d7
    Additional output forming options described here: Command line arguments.
  • Step 3: Once the problem is diagnosed normal operations can be resumed with the following
    command: /etc/init.d/iec101-­slave start
IEC 60870-­5­-101 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
-R [ –readyfile ] Ready notification file