15.2 IEC 61850 Server
WCC Lite can act as a IEC 61850 server to serve data to remote SCADA systems. For example, WCC Lite can be used to acquire data from various protocols (Modbus, IEC 60870-5-103, etc.), this data can be redirected and propagated further to a single or multiple IEC 61850 clients. IEC 61850 Server supports TCP and TLS connection types. TCP connection can be secured with password authentication.
WCC Lite IEC 61850 Server implementation defines four command types which are described by their control model:
- Case 1: Direct control with normal security (direct-operate);
- Case 2: SBO control with normal security (operate-once or operate-many);
- Case 3: Direct control with enhanced security (direct-operate);
- Case 4: SBO control with enhanced security (operate-once or operate-many).
Normal security commands are considered for execution if the command signal is found in Excel configuration. There aren’t any additional checks in command execution in any master protocol.
Enhanced security commands need feedback from master protocol to either to succeed or fail. If feedback is not received within command_ack_timeout_ms timeframe, the command is considered as failed.
Command value attributes (e.g. stVal) must be updated separately (if they need to be updated).
When using SBO commands, select is not routed to master protocol and select logic is performed only in IEC 61850 Server protocol.
Configuring data points
To use IEC 61850 Server in WCC Lite, it has to be configured via an Excel configuration and data model must be uploaded. This configuration contains two Excel sheets where parameters have to be filled in - Devices and Signals.
IEC 61850 Server parameters for Devices tab
(when not specified)
|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 61850 Server|
|bind_address||string (IP address format)||IP address of and interface to use with server||No||0.0.0.0|
|host||string (IP address format)||
IP address list of allowed IPs (separated with spaces)
TCP communication port
|Yes||“NONE”, “PASSWORD”, “TLS”|
Authorization password for server device
|Yes ( for PASSWORD)|
Local certificate for TLS connection
|Yes (for TLS)|
|tls_peer_certificate||string||Certificate authority file for TLS connection||Yes (for TLS)|
|tls_private_key||string||File consisting of private key for TLS connection||Yes (for TLS)|
|ied_name||string||Name of an Intelligent Electronic Device||Yes|
|originator||string||Origin identification for device||No|
|model_filename||string||Filename of server model, without .server extension||Yes|
Timeframe (ms) in which enhanced-security commands must be acknowledged
Report control blocks buffer size in bytes
Unbuffered report control blocks buffer size in bytes (Default: 65513)
IEC 61850 Server parameters for Signals tab
(when not specified)
|signal_name||string||User-friendly signal name||Yes|
|device_alias||string||Device alias from a Devices tab||Yes|
|signal_alias||string||Unique alphanumeric name of the signal to be used||Yes|
|enable||boolean||Enabling/disabling of an individual signal||No||1||0||1|
|log||boolean||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|
|number_type||string||Number format type (BOOLEAN, FLOAT, INT16, etc.)||Yes||BOOLEAN, INT8, INT16, INT32, INT64, INT128, INT8U, INT24U, INT32U, FLOAT32, FLOAT64, ENUMERATED, OCTET STRING 64, OCTET STRING 6, OCTET STRING 8, VISIBLE STRING 32, VISIBLE STRING 64, VISIBLE STRING 65, VISIBLE STRING 129, VISIBLE STRING 255, UNICODE STRING 255, TIMESTAMP, QUALITY, CHECK, CODEDENUM, GENERIC BITSTRING, CONSTRUCTED, ENTRY TIME, PHYCOMADDR, CURRENCY, OPTFLDS, TRGOPS|
|ld_instance||string||Instance of a logical device||Yes|
|ln_class||string||Logical node class type||Yes|
|ln_instance||integer||Instance of a logical node||No|
|ln_prefix||string||Prefix of logical node string||No|
|cdc||string||Common Data Class (CDC) name||Yes||SPS, DPS, INS, ENS, ACT, ACD, MV, CMV, SAV, SPC, DPC, INC, ENC, BSC, ISC, APC, BAC|
|data_object||string||Name of data object in dataset||Yes|
|da_value||string||Name of a data attribute value node||Yes|
|da_fc||string||Functional constrain for data object||Yes||ST,MX, CO, SP|
Model of output control
Yes (for commands)
Device status signals
IEC 61850 has an additional signal which can be configured to show communication status. It is used to indicate if the client device has disconnected from server (WCC Lite). To configure such signal for IEC 61850 protocol, job_todo and tag_job_todo fields with string values are required. For IEC 61850 server required parameters for status signal will be: signal_name device_alias, signal_alias, number_type, job_todo and tag_job_todo. Job_todo value must be device_status and for tag_job_todo there are 4 variations: communication_status, device_running, device_error, uknown_error. Each signal has 4 possible values and are based on the same logic. If signal returns value of 0, it means unknown error has appeared, 1 – device or protocol connection is on and working properly, 2 – device is off or protocol is disconnected, 3 – error or service is down.
Converting and uploading data model
To use IEC61850 Server protocol in WCC Lite, user must upload a data model in specific format (file extension .server). These data models can be converted from SCL files (.icd, .cid or .scd files). To convert a data model, the user must use WCC Excel Utility. There’s a separate tab for this operation as shown in picture below.
Converted file can be uploaded in WCC Lite web interface, Protocol Hub section. Current model can be also downloaded in the same page as shown in picture below.
Debugging an IEC 61850 server application
If the configuration for IEC 61850 Server is set up, a handler for the protocol will start automatically. If the configuration is missing or contains errors, the protocol will not start. It is done intentionally to decrease unnecessary memory usage.
If IEC 61850 Server 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 the link is not functioning properly.
To launch a debugging session, a user should stop
iec61850-server process and run
iec61850-server command with respective flags as you can see below:
-h [--help] Show help message -c [--config] arg Configuration file location -V [--version] Show version -d [--debug] arg Set Debug level -r [--redis] Show Redis messages -C [--commands] Show command messages -R [--readyfile] arg Ready notification file