IEC 60870 Server¶

Overview¶

This feature is available starting with PROCON-Connect v1.4.0.

The IEC 60870 server in PROCON-Connect provides process data and status information for higher-level control systems. It enables plant components to be reliably integrated into energy distribution and automation structures. The server receives and processes IEC 60870 telegrams and makes the information they contain available in the form of tags within PROCON-Connect.

This tag mapping seamlessly integrates measured values, switching commands, events, and status information from IEC 60870 telegrams into the software. The data can then be used for process connections, logic and function modules, visualizations, and for forwarding to other protocols. The IEC 60870 server thus serves as a central interface for securely and flexibly integrating IEC-compliant field devices into the overall architecture of PROCON-Connect.

Server overview¶

An overview of how to manage existing servers and a starting point for adding new servers.

Name: The unique name of the server. This can be chosen freely when adding the server and is used solely for identification purposes in the overview.
Server type: The server can be type 104 (TCP) or 101 (serial). The server type affects the configuration options when adding a server, as well as its communication protocol.
Status: Possible statuses are Active, Stopped, Error or Unlicensed. Only an active server can send and receive messages.
Options menu: The starting point for manually adding information objects, importing information objects, or editing and deleting the server.

Configure the server¶

You can add a new server and configure it directly using the button (1).

You can adjust the configuration of an existing server via the Options menu (2).

The following parameters can be configured on a server:

Name: The server’s name is displayed on the overview page and is intended to make it easier to identify the server.
Enable: This setting allows you to enable or disable the server. Only an enabled server can send and receive messages.
Pulse Configuration: The parameters defined here determine how long the outputs are set when a pulse command is executed. Pulse handling is handled by the 60870 server.
- Default duration (ms): Specifies the default pulse duration used for control commands when no alternative pulse duration is specified. Typically in the range 50–500 ms.
- Short duration (ms): Defines a shortened pulse duration for specific control commands that require minimal time.
- Duration (ms): Sets the extended pulse duration.
Connection status tag mapping: Mapping of the connection status to a logical or numeric tag.
- Logical Day: 0 = No clients connected. 1 = At least one client connected.
- Numeric tag: 0 = no clients connected. n = n clients connected. Example: 2 = 2 clients connected at the same time.

Configuring the 104 server¶

These parameters are specific to 104:

Server address: The binding address and port through which the server should be accessible. The default port is 2404. In u-OS, the binding address and port cannot be configured; the address 0.0.0.0 and port 2404 are always used.
T1: Timeout for transmitted APDUs in I/U format (in seconds). If the timeout expires without an acknowledgement, the connection is closed. This is used by the sender to determine whether the receiver has failed to acknowledge a message.
T2: Time limit for message acknowledgement (in seconds). This time limit is used by the recipient to determine the point in time by which the message acknowledgement must be sent.
T3: Time limit for sending test telegrams when the connection is inactive.
K: Number of unacknowledged APDUs in I-format. The sender terminates the transmission after K unacknowledged I-messages.
W: Number of unacknowledged APDUs in I-format. The recipient will acknowledge them after no more than W messages.
Low-priority queue size: Used for cyclic and event/spontaneous data transmissions. The queue operates on a FIFO basis. If the queue is full when a new telegram is added, the oldest telegram is removed.
High-priority queue size: Used for responses to commands. The queue operates on a FIFO basis. If the queue is full when a new telegram is added, the oldest telegram is removed.

Client Whitelisting¶

Whitelisting allows you to specify any number of IP addresses. By default, the list is empty, and any client can connect to the server. The list serves as the basis for setting up redundancy groups, since the server must be aware of the clients for this purpose.

The following mechanics apply:

If no client has been created, connections from all clients are allowed; no IP-based verification takes place.
If at least one client has been created, only connections from listed clients whose ‘Enabled’ parameter is active will be permitted.
If only clients are listed and they are all disabled, clients will not be able to establish a connection at all.

Configuring the 101 server¶

These parameters are specific to 101:

Serial port: The name of the serial port to be used for communication, e.g. COM1.
Baud rate: The speed of physical data transmission in bauds. The default is 9600.
Data bits: Number of data bits. The default is 8.
Stop bits: Number of stop bits. The default is 1.
Parity: None, even or odd parity can be set. The default is None.
Mode: Connection mode. Possible options are unbalanced and balanced. The default is unbalanced.
Address length (bytes): Address length in bytes. The default is 1 byte.
Confirmation timeout (ms): Timeout for confirmation. The default is 500 ms.
Local link-layer address: The default is 1.
Remote link-layer address: The default is 1.
Common Address (CA) – Bytes: Length of the CA in bytes. Can be 1 or 2 bytes. The default is 2.
Information Object Address (IOA) – Bytes: Length of the IOA in bytes. Can be 1 to 3 bytes. The default is 3.
Transmission cause (COT) – Bytes: Length of the CA in bytes. Can be 1 or 2 bytes. The default is 2.

Overview of information objects¶

To access the information object overview, first navigate to the IEC 60870-5 server overview page. Clicking on a server entry opens its information object overview.

Name: Name of the information object. Displayed in the information object overview. Optional.
IEC data type: The data type of the information object.
CA: The information object’s shared address in dual notation: integer and byte-by-byte.
IOA: Information object address in dual notation: integer and byte-by-byte.
Tags: A list of all tags assigned to the information object.
Options menu: The starting point for editing or deleting an existing information object.

When configuring information objects, multiple tags are assigned. The link between an information object and tags is established via dependencies. The configuration is automatically checked for consistency when the overview is opened. Any inconsistencies are indicated by a warning triangle in the first column of the information object overview. Further information is displayed in a tooltip when the mouse pointer is positioned over the warning triangle. During the check, the value ranges of the assigned tags are examined in conjunction with the IEC data type.

Configure information objects¶

You can add a new information object via the Options menu for the relevant server. There you will find the option Add information object (1).

You can edit an existing information object via its Options menu (2).

General parameters¶

The following parameters can always be configured in an information object. These parameters are not dependent on the IEC data type.

Name: Name of the information object. Displayed in the information object overview. Optional.
Common Address (CA): The CA can be entered in the left-hand field as a single number or in the right-hand field byte by byte. [1; 65534] are station addresses; 65535 is the global address.
Information Object Address (IOA): The IOA can be entered as a single number in the left-hand field or byte by byte in the right-hand field.
IEC data type: The IEC data type can be selected from a drop-down menu. The selection affects the configuration options below, such as the available tag mappings.

Parameters in the monitoring direction¶

The following parameters are available for all IEC data types in the monitoring direction:

General query: The information object is included in the response to the general query.
Group interrogation: Information objects in the monitoring direction can be assigned to groups. Any number of groups can be assigned in parallel. It is also possible to combine this with the general query.
Cyclic transmission (COT1): Information objects in the monitoring direction can be transmitted cyclically.
Event/Spontaneous Transmission (COT3): Information objects in the monitoring direction can be transmitted when their values change. Absolute and percentage thresholds can be defined, by which the value must have changed compared to the last transmission.

Depending on the IEC data type, the following tag mappings in the monitoring direction are possible:

Value: The tag whose value is to be transferred.
Quality: A field containing quality information. The quality information is represented as an integer. The quality information can be extracted bit by bit, for example at the Codesys level.
Transient: A Boolean tag indicating whether the information object is currently in a transitional state. true = transitional, false = steady-state.
Timestamp: The tag containing the timestamp. If no tag is selected, the most recent timestamp from the other tag assignments (Value, Quality, Transient) is used. The source of the timestamp depends on the driver. For driver-specific details, see Driver settings.

IEC data type	Value	Quality	Transient	Timestamp
[001] M_SP_NA_1 - Single Point Value	x	x
[003] M_DP_NA_1 - Double Point Value	x	x
[005] M_ST_NA_1 - Step Position Information	x	x	x
[009] M_ME_NA_1 - Measured Value, Normalized	x	x
[011] M_ME_NB_1 - Measured Value, Scaled	x	x
[013] M_ME_NC_1 - Measured Value, Short	x	x
[015] M_IT_NA_1 - Integrated Totals	x	x
[021] M_ME_ND_1 - Measured Value Without Quality	x
[030] M_SP_TB_1 - Single Point Value with CP56Time2a	x	x		x
[031] M_DP_TB_1 - Double Point Value with CP56Time2a	x	x		x
[032] M_ST_TB_1 - Step Position Information with CP56Time2a	x	x	x	x
[034] M_ME_TD_1 - Measured Value, Normalized with CP56Time2a	x	x		x
[035] M_ME_TE_1 - Measured Value, Scaled with CP56Time2a	x	x		x
[036] M_ME_TF_1 - Measured Value, Short with CP56Time2a	x	x		x
[037] M_IT_TB_1 - Integrated Totals with CP56Time2a	x	x		x

Parameters in the command direction¶

Depending on the IEC data type, the following tag mappings in the command direction are possible:

Value: The tag whose value is to be transferred.
Qualifier: A tag containing quality information. The quality information is represented by an integer.
Select/Execute: A Boolean tag that can be used to prepare messages. true = Execute, false = Select.
Transmission cause: A tag containing information on whether the command is an ACTIVATION or a DEACTIVATION. This can be evaluated in the PLC to cancel the execution of a command currently in progress.
Timestamp: The tag containing the timestamp. If no tag is selected, the most recent timestamp from the other tag assignments (Value, Quality, Transient) is used. The source of the timestamp depends on the driver. For driver-specific details, see Driver settings.

IEC data type	Value	Qualifier	Select/Execute	Cause of transmission	Timestamp
[045] C_SC_NA_1 - Single Command	x	x	x	x
[046] C_DC_NA_1 - Double Command	x	x	x	x
[047] C_RC_NA_1 - Step Command	x	x	x	x
[048] C_SE_NA_1 - Setpoint Command, Normalized	x	x	x	x
[049] C_SE_NB_1 - Setpoint Command, Scaled	x	x	x	x
[050] C_SE_NC_1 - Setpoint Command, Short	x	x	x	x
[058] C_SC_TA_1 - Single Command with CP56Time2a	x	x	x	x	x
[059] C_DC_TA_1 - Double Command with CP56Time2a	x	x	x	x	x
[060] C_RC_TA_1 - Step Command with CP56Time2a	x	x	x	x	x
[061] C_SE_TA_1 - Setpoint Command, Normalized with CP56Time2a	x	x	x	x	x
[062] C_SE_TB_1 - Setpoint Command, Scaled with CP56Time2a	x	x	x	x	x
[063] C_SE_TC_1 - Setpoint Command, Short with CP56Time2a	x	x	x	x	x

Writing feedback tag assignment¶

In the command direction, additional tag mappings are required in order to be able to associate a controller’s responses with a specific command.

Request counter: The value of this numeric tag is automatically incremented as soon as the associated command is received. Connected controllers can monitor changes to this value to determine whether the command has been triggered.
Response counter: Connected controllers should increment the response counter to the value of the request counter once the command has been processed. This informs the IEC 60870 server that processing has been completed. The server then acknowledges the completion of processing to the client with COT_ACTIVATION_TERMINATION (COT10).
Response status: Connected controllers should set this Boolean tag to true if the command was executed successfully. Otherwise, the value should be set to false. The response status must be set before the response counter is set. If the status is false, COT_ACTIVATION_TERMINATION (COT10) is sent with the negative flag set.

The Write Feedback Tag Assignment block is used to link a command and its response on the 60870 server:

The command is sent to the PLC and the request counter for the PLC is incremented.
The PLC executes the command in accordance with its internal logic.
The result can be written to the response status.
The PLC can then set the response counter equal to the request counter.
The 60870 can now evaluate the response Status and forward it to the client.

Transmission of the corresponding measured value (COT 11)¶

Linking a measured value to a command. Once the command has been executed, this measured value is transmitted via COT 11.

Associated measurement value: The tag containing the measurement value to be transmitted.

Import information objects¶

The configuration of 60870 servers is often based on Excel-based lists of data points provided by energy suppliers on a plant-specific basis. The CSV-based import of information objects is designed to enable this information to be efficiently transferred into the system.

The edited CSV file can then be imported into two systems: Codesys and PROCON-Connect.

An import script is available for Codesys which generates a suitable variable in the global variable list (GVL) based on the specified variable name and IEC data type. The script is provided as a Codesys package and can be installed accordingly.

For the 60870 server, the Import information objects option can be used to create the information objects.

During the import process, you can select a previously created Codesys connection. If the CSV file contains tag names, these variable names are automatically imported into the variable list of the selected Codesys connection and mapped to the information object.

For all other drivers, the relevant tags must first be imported manually. During import, PROCON-Connect then searches for tags with the same name and automatically assigns them to the information object.

Although this mechanism is based on the tag name, tags are referenced in information objects by their technical ID; in other words, renaming a tag at a later date does not remove the association.

Import entry point¶

The starting point is the Server overview. The Import Information Objects option can be accessed via the Options menu of an existing 60870 server. A dialogue box will open. From this dialogue box, you can download the required CSV template or upload a file that has already been prepared for import.

Configuring the CSV file¶

The field separator is the character ;
The file and import functions support the UTF-8 character set.
The CSV file contains the following columns (* = required field):

CSV column	Parameter	Description
name	Name	Purpose of the signal. Displayed in the UI to aid identification. Data type: String.
datatype *	IEC data type	IEC data type number, e.g. 20 for general query. Data type: Numeric, [0; 126].
caLow *	CA Low	Low byte of the Common Address of the ASDU (Application Service Data Unit). If, in serial configurations, a CA is selected using only one byte, only the CA L field should be used for import. The CA H field remains empty and is not a mandatory field. Data type: Numeric, [0, 127].
caHigh *	CA High	Highest byte of the ASDU (Application Service Data Unit) shared address. Data type: Numeric, [0, 127].
ioaLow *	IOA Low	Low byte of the Information Object Address (IOA). Data type: Numeric, [0; 127].
ioaMid *	IOA Mid	Middle byte of the Information Object Address (IOA). If, in serial configurations, the IOA is selected using only two bytes, IOA L and IOA H must be used for the import. In this case, IAM M remains empty and is not a mandatory field. Data type: Numeric, [0; 127].
ioaHigh *	IOA High	High byte of the Information Object Address (IOA). Data type: Numeric, [0; 127].
valueTagName	Value	A tag representing the value. Data type: String.
valueTagComment	Value comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
timestampTagName	Timestamp	Name of the tag representing the CP56Time2a timestamp. Data type: String (CP56Time2a timestamp).
timestampTagComment	Timestamp comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
qualityTagName	Quality	Name of the tag that represents the quality information in the monitoring direction. Data type: Numeric.
qualityTagComment	Quality comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
qualifierTagName	Qualifier	Name of the tag that represents the quality information in the command direction. Data type: Numeric.
qualifierTagComment	Qualifier comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
selectExecuteTagName	Select/Execute	Name of the tag used to prepare messages. Data type: String.
selectExecuteTagComment	Select/execute comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
transientTagName	Transient	Name of the tag representing the transition state. Data type: String.
transientTagComment	Transient comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
causeOfTransmissionTagName	Cause of transmission	Name of the tag that determines whether the command is an ACTIVATION or a DEACTIVATION. Data type: String.
causeOfTransmissionTagComment	Cause of transmission comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
requestCounterTagName	Request counter	Name of the tag representing the request counter. Data type: String.
requestCounterTagComment	Request counter comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
responseCounterTagName	Response counter	Name of the tag representing the response counter. Data type: String.
responseCounterTagComment	Response counter comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
responseStatusTagName	Response status	Name of the tag representing the response status. Data type: String.
responseStatusTagComment	Response status comment	Comment on the tag. When imported into Codesys, this is written as a source code comment after the variable. Data type: String.
spontaneousEnabled	Event/Spontaneous transmission (COT3)	`TRUE` = Spontaneous transmission enabled. `FALSE` or `[empty]` = Spontaneous transmission disabled. Data type: Boolean.
spontaneousThresholdType	Threshold type	The threshold check can be performed as ‘not at all’, ‘absolutely’ or ‘relatively’. Data type: Enum. The following keywords are available during import: `Procentual` - Enables percentage-based threshold checking based on the most recently transmitted value. A threshold value must be entered. `Absolute` – Enables percentage-based threshold checking based on the most recently transmitted value. A threshold value must be entered. `[empty]` - No threshold check is performed.
spontaneousThresholdValue	Threshold	This value must be specified if the threshold type has been set to percentage or absolute. A full stop must be used as the decimal separator, for example: `3.75`. Data type: Numeric, positive numbers.
stationInterrogationEnabled	Group interrogation	`TRUE` = General interrogation (COT 20) or general counter interrogation (COT 37) enabled. `False` or `[empty]` = General query/general counter intorrogation disabled. Data type: Boolean.
interrogationGroups	Groups	Configuration for group queries. `1–16` for measured values. `1–4` for counters. Multiple groups can be specified separated by commas, e.g. `1, 16`. Data type: String.
cyclicPublishIntervalSec	Cyclic transmission (COT1)	A positive integer can be entered. The unit is seconds. The import automatically enables cyclic transmission if a value is specified. If the field is left blank, cyclic transmission is not enabled. Data type: Numeric, positive numbers.

Import trends¶

Global address¶

CA 65535 is interpreted as a global address. A query to station 65535 therefore returns all values from stations 1 to 65534.

Writing behaviour of tag mappings¶

When using the CODESYS, OPCUA or TIA v2 drivers: All assigned tags of an information object (e.g. value and qualifier) are written to the PLC simultaneously.

For all other drivers, multiple write requests are used. The transfer to the process is therefore not atomic in this case.

Information objects in the event log¶

The event log allows you to track the communication of the 60870 server.

Filter: The event log can be filtered to 60870, as shown in the screenshot, so that only relevant events are displayed.
Level: To display communication messages, the log level of the 60870-5 service must be set to debug in the event log configuration.
Content: Details regarding the transmission of the information object and the values transferred are displayed. The information shown depends on the IEC data type. In addition to the parameters already defined, the following parameters may also appear in the log:
- OA (Origin Address): When updating measured values, the origin address is set to 0. When responding to commands, the origin address of the command is used.
- Negative: Error bit for responses to commands. 0 = no error, 1 = error. Errors may occur, for example, if the PLC is unreachable or returns an error.