FreyrSCADA IEC 60870-5-101 Client Stack Interoperability
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8 Interoperability
This companion standard presents sets of parameters and alternatives from which subsets have to be
selected to implement particular telecontrol systems. Certain parameter values, such as the number of octets in
the COMMON ADDRESS of ASDUs represent mutually exclusive alternatives. This means that only one value of the
defined parameters is admitted per system. Other parameters, such as the listed set of different process
information in command and in monitor direction allow the specification of the complete set or subsets, as
appropriate for given applications. This Clause summarizes the parameters of the previous Clauses to facilitate a
suitable selection for a specific application. If a system is composed of equipment stemming from different
manufacturers, it is necessary that all partners agree on the selected parameters.
The selected parameters should be marked in the white boxes as follows:
Function or ASDU is used as standardized (default)
The possible selection (blank, X, R, or B) is specified for each specific Clause or parameter.
NOTE In addition, the full specification of a system may require individual selection of certain param eters for certain parts of the system,
such as the individual selection of scaling factors for individually addressable measured values.
8.1 System or device
(System-specific parameter, indicate the station’s function by marking one of the following with “X”)
System definition
Controlling station definition (master)
Controlled station definition (slave)
8.2 Network Configuration
(Network-specific parameter, all configurations that are used are to be marked with an “X”)
Point-to-point Multipoint-party line
Multiple point-to-point Multipoint-star
Function or ASDU is used in reverse mode
Function or ASDU is used in standard and reverse mode
R
B
Function or ASDU is not used
FreyrSCADA IEC 60870-5-101 Client Stack Interoperability
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8.3 Physical Layer
(Network-specific parameter, all interfaces and data rates that are used are to be marked with an “X”)
Transmission speed (control direction)
Unbalanced interchange Unbalanced interchange Balanced interchange
Circuit V.24/V.28 Circuit V.24/V.28 Circuit X.24/X.27
Standard Recommended if >1 200 bit/s
100 bit/s 2400 bit/s 2400 bit/s 56000 bit/s
200 bit/s 4800 bit/s 4800 bit/s 64000 bit/s
300 bit/s 9600 bit/s 9600 bit/s
600 bit/s 19200 bit/s
1200 bit/s 38400 bit/s
Transmission speed (monitor direction)
Unbalanced interchange Unbalanced interchange Balanced interchange
circuit V.24/V.28 circuit V.24/V.28 circuit X.24/X.27
Standard Recommended if >1 200 bit/s
100 bit/s 2400 bit/s 2400 bit/s 56000 bit/s
200 bit/s 4800 bit/s 4800 bit/s 64000 bit/s
300 bit/s 9600 bit/s 9600 bit/s
600 bit/s 19200 bit/s
1200 bit/s 38400 bit/s
8.4 Link Layer
(Network-specific parameter, all options that are used are to be marked with an “X”. Specify the
maximum frame length. If a non-standard assignment of class 2 messages is implemented for
unbalanced transmission, indicate the type ID and COT of all messages assigned to class 2.)
Frame format FT 1.2, single character 1 and the fixed time out interval are used exclusively in this companion
standard.
Link transmission procedure Address field of link
Balanced transmission Not present (balanced transmission only)
Unbalanced transmission One octet
Two octets
Structured
Frame length Unstructured
255 Maximum length L (control direction)
255 Maximum length L (monitor direction)
Configurable Time during which repetitions are permitted (Trp) or number of repetitions
FreyrSCADA IEC 60870-5-101 Client Stack Interoperability
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When using an unbalanced link layer, the following ASDU types are returned in class 2 messages (low priority) with
the indicated causes of transmission:
The standard assignment of ASDUs to class 2 messages is used as follows:
Type identification
Cause of transmission
9, 11, 13, 21
<1>
Type identification
Cause of transmission
Configurable
Configurable
NOTE In response to a class 2 poll, a controlled station may respond with class 1 data when there is no class 2 data available.
8.5 Application Layer
Transmission mode for application data
Mode 1 (least significant octet first), as defined in 4.10 of IEC 60870-5-4, is used exclusively in this
companion standard.
Common address of ASDU
(System-specific parameter, all configurations that are used are to be marked “X”)
One octet Two octets
Information object address
(System-specific parameter, all configurations that are used are to be marked “X”)
One octet structured
Two octets unstructured
Three octets
Cause of transmission
(System-specific parameter, all configurations that are used are to be marked “X”)
One octet Two octets (with originator address)
Set to zero in case of no originator address
A special assignment of ASDUs to class 2 messages is used as follows:
