Reference string

Nearly every service defined in the IEC 61850 is utelizing a so-called object reference. This could be for example the reference to the object one want to read using the GetDataValue service. This object reference is a pointer into the data model. A typical example could look like so:

The reference string can be split up into 3 parts:

Before “/“

This is the pointer to the logical device containing the IEDs name and the logical device instance. This big of the reference can also be expressed using the logical device name attributes instead, a concept defined as functional naming. (see Logical Device (LD) ). So the above example could translate from IEDLD1 to LDName1.

Before the FIRST “.“

This part is the pointer to the logical node containing the logical node prefix 3ph, the logical node class MMXU and the logical node instance 1.

Data reference “the rest“

Is the pointer to the object in question. In the above case to the sub data attribute f that is part of a AnalogueValue magwhich is defined in a vector cVal that is definde in the CDC MV phsA which is defined as a child in the CDC WYE A. The endpoint must not neccassary be the leaf data attribute. There are cases where you wan to know all the data within the data object A and as such the object reference ends there.