IEC 60870-5-103 is defined as a companion standard for the informative element of protection equipment. While the official IEC 60870-5-103 standard dates back to 1997, the protocol has its roots in the VDEW6 communication protocol from the late 1980’s. A VDEW6 device can be seen as a subset of an IEC 60870-5-103 device but not the opposite.
IEC 60870-5-103 defines communication for a serial, unbalanced link only. Communication speeds are defined as either 9600 or 19200 baud.
Standard documentation
| IEC 60870 document part | Description |
|---|---|
| 5-1 | Transmission frame formats |
| 5-2 | Link transmission procedures |
| 5-3 | General structure of application data |
| 5-4 | Definition and coding of application information elements |
| 5-5 | Basic application functions |
| 5-6 | Conformance testing guidelines |
| 5-103 | Companion standard for the informative interface of protection equipment. |
Interoperability and interchangeability
An IEC 60870-5-103 device can be interoperable and interchangeable or only interoperable. Interoperability means that any required application data in the device, which can be coded into an IEC 60870-5-103 data type, can be mapped into the IEC 60870-5-103 address space. This data is recognized by any IEC 60870-5-103 master.
Interchangeability means supporting the application data (informative elements) whose semantics are pre-defined by the IEC 60870-5-103 standard. However, only a very limited set of application data informative elements has been defined by the standard. It should also be noticed that these sets of data are mainly defined for a single-function protection IED. The 620 series IEDs in turn are multifunctional protection and control IEDs whose internal data model is based on the IEC 61850 standard.
Interoperability list
The standard requires the IEC 60870-5-103 device to provide an interoperability list, which actually is more an interchangeability list. See the point list manual for a complete list of all IEC 60870-5-103 data available in a specific IED.
Default data mapping principle
Whenever possible, process data is mapped into standard IEC 60870-5-103 function types and information numbers. When this is not possible, the process data is mapped into private function types and information numbers. General principle of the mapping is to keep all process data belonging to the same function design inside the same IEC 60870-5-103 function type definition. However, if this default mapping principle causes interoperability problems with older installations, every available IEC 60870-5-103 process data point can be freely remapped with PCM600. All the mapped data is not in use by default.