Measurands; Class 2 Measurands; Extended Class 2 Measurand Frames - ABB Relion 615 series Manual

Section 3
Vendor-specific implementation
3.3.4
3.3.4.1
3.3.4.2
18

Measurands

Measurand object transmission is defined by the IEC 60870-5-103 standard. The
standard does not define any method for transporting integer values like counters or
enumeral objects.
Measurands are transmitted as a set of Class 2 data, referred to as a Class 2
measurands frame. According to the standard the coding of IEC 60870-5-103
measurand objects must be 13 bit signed values in the range of -1...+1.
When an IEC 60870-5-103 measurand, for example phase current, is scaled as 2.4,
it means that the measurand value 1 corresponds to 2.4*In, measurand value 0.5
corresponds to 1.2*In, and so on. If the measurand value in this case exceeds
2.4*In, the IEC 60870-5-103 object value saturates at its maximum value and an
overflow flag is set in the IEC 60870-5-103 object.

Class 2 measurands

The interchangeable part of the IEC 60870-5-103 standard defines that only five
Class 2 measurands frames exist. Measurands transmitted in these five Class 2
frames relates to current and voltage values only. Allowed scale factors, actually
meaning |max values| of per unit coded measurands, are 1.2 or 2.4. RE_615
supports all five interchangeable Class 2 measurand frames defined by the standard.
Table 6: Interchangeable Class 2 measurand frames
FrameNo ASDU
FUN
1 3
2 3
3 3
4 3
5 9
1) FUN = 0 means that the Function type is coded as the Device function type which in turn is defined
by the setting parameter Configuration/Communication/IEC 60870-5-103/DevFunType n.

Extended Class 2 measurand frames

IED-dependent frames 6 and 7
The IED also provides two private Class 2 frames that are IED type- and variant-
dependent. These Class 2 frames are in the IED referred to by frame numbers 6 and
7. These Class 2 frames contain most of the transferable measurands produced by
the IED in question. Frame 6 contains frequently changing updated values and
frame 7 adds more, less frequently updated values, to the contents of frame 6.
INF Num of data
1)
0 144
0 145
0 146
0 147
0 148
1MRS756710 C
Data in the Class 2 frame
1 IL2
2 IL2, U12
4 IL2, U12, P3, Q3
2 Io, Uo
9 IL1, IL2, IL3, UL1, UL2, UL3, P3,
Q3, pf
Communication Protocol Manual
615 series