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1MRS755385
Communication Gateway
User’s Guide
COM 610 *2.1
IECmodeling
Fig. 2.5.-2 Overview of IEC 61850 model usage
Protection and control products are connected to the gateway via OPC interfaces.
Although OPC provides means to access data on devices, it does not specify the
semantics of the data. This means that the same information is available in different
formats depending on which device and communication protocol is used. In
addition, services, such as breaker operation, vary among devices and protocols.
These differences complicate the reuse of gateway applications. To overcome this
problem, all the applicable data and services are remodeled in OPC servers
according to the data and service model specified in the IEC 61850 standard. This
provides a protocol and device independent interface between the applications and
the process. Fig. 2.5.-2 presents an overview of the IEC 61850 model usage.
The smallest unit in the IEC 61850 modelling is a data attribute which is linked to
an OPC item in the OPC server. A data attribute can be, for instance, the state value
of a double point object (stVal), quality information (q), or timestamp (t). In the OPC
server some of the services are also mapped to the same level as the attributes. This
means that, for example, control services (such as ctlOperOn, ctlOperOff) for
operating a double point object are available as OPC items.
IEC-5-101/104
Slave
IEC61850 Data
Modeling
OPC Client
COM (DCOM)
CET
OPC Client
IEC61850 Data
Modeling
IEC61850
OPC Server
IEC61850
Protocol Stack
IEC61850 Data
Modeling
LON OPC Server
LON
Protocol Stack
IEC61850 Data
Modeling
SPA OPC Server
SPA
Protocol Stack
IEC61850 Data
Modeling
IEC103
OPC Server
IEC103
Protocol Stack
