IEC 60870-5-103 is an international standard, released by IEC (International Electrotechnical Comission) at the beginning of the 90ies. It allows the coupling of a central unit to several protection devices and is primarily used in the energy sector. The standardized function range is especially designed for the communication with protection devices and therefore it's difficulty to adapt it to other applications.

The protocol is based on the EPA architecture (Enhanced Performance Architecture), defining only the physical link and application layer of the OSI layer model.

IEC 60870-5-103 is mainly used for relatively slow transmission media on asynchronous V.24 (RS232) and RS485 interfaces. Connection via fibre optics is also covered by the standard. The transmission speed in general is specified with a maximum of 19200 Baud.

IEC 60870-5-103 is a 'Companion Standard' and is extended by the following standards:

IEC 60870-5-1
defines different frame formats, IEC 60870-5-103 applies only the FT1.2 format
IEC 60870-5-2
defines the transmission mode on the link layer
IEC 60870-5-3
defines the basic application data structure
IEC 60870-5-4
defines how information elements are encoded
IEC 60870-5-5
defines basic application layer functions

Interoperability between devices by different vendors is ensured by the interoperability list, which is defined by the standard. In the list, the function range is defined for each device by marking the applicable functions. The common denominator between different vendor lists defines the possible function range.

In addition to standard protocol functions, IEC 60870-5-103 also accommodates extensions for proprietary vendor-specific functions. These are used extensively by manufacturers of protection devices. As a result compatibility between devices by different vendors cannot always be ensured. The function range can further be extended by using generic data objects, which allow the transmission of any kind of information in both directions.

ISO/OSI Model

7	Application Layer	IEC 60870-5-103 IEC 60870-5-5, IEC 60870-5-4
6	Presentation Layer	n/a
5	Session Layer	n/a
4	Transport Layer	n/a
3	Network Layer	n/a
2	Link Layer	unbalanced IEC 60870-5-2 IEC 60870-5-1 (FT 1.2)
1	Physical Layer	EIA RS485, RS232 (V.24), Fibre Optics

Supported Standardized Information Types

Control Direction	Double Command
Monitoring Direction	Double indication [2 bit] with quality and time tag
	Double indication [2 bit] with quality, time tag and relative time
	Measured normalized value with quality
	Measured floating point value with quality, time tag and relative time

Selection of Supported Generic Information Types

Control Direction	Single indication [1 Bit]
	Double indication [2 bit]
	ASCII 8-bit code
	Measured scaled value
	Measured floating point value
Monitoring Direction	Single indication [1 Bit]
	Double indication [2 bit]
	ASCII 8-bit code
	Measured scaled value
	Measured floating point value

Protocol Features

Physical Layer	PCM, half-duplex
Link Layer	Party line or point to point
Application Layer	On-demand transmission (e. g. double indications, analogs, ...) Spontaneous transmission (e. g. double indications with time tag, ...) Command execution Clock synchronization
Address Space	Link address: 0..255 Common Address of ASDU: 1..255 Function Type: 0..253 Information number: 0..255

Implemented Protocol Stacks

IEC 60870-5-103, Master

IEC 60870-5-103, Slave

Applicable Products

	ipConv	Universal protocol converter for highest degree of flexibility Details...
	ipConvOPC	Softwarepackage for conversion between OPC DA 2.05 Server and standard protocols Details...
	Fink WinPP Protocol Simulator	Simulationsoftware for IEC 60870-5-101, IEC 60870-5-103, IEC 60870-5-104, SINAUT 8-FW 16-1024 PCM/DPDM Details...

References

COMETA, Spain
Details...

Spain

ipConv

IEC 60870-5-103, Master / IEC 60870-5-101, Slave / IEC 60870-5-101, Master / Simatic TDC, Master /