Class 2 Data; Class 2 Measurand Sets (Asdu Frames); Class 2 Value Scaling; Default Mappings - ABB RET 54 Series Technical Reference Manual, General

RET 54_
10.5.
10.5.1.
10.5.2.
10.6.
110
Transformer Terminal
Technical Reference Manual, General

Class 2 data

The measurement (analog) values are transported to the control system as a response
to a class 2 request command. The class 2 data is always cyclically updated
(COT=2). Refer to Table 9.7.-1 on page 116 for measurement data.

Class 2 measurand sets (ASDU frames)

The IEC 60870-5-103 standard defines the measurands to be transmitted as either
Meas I (typeId 3) or Meas II (typeId 9) ASDU frames. According to the standard,
the Meas I ASDU can have four different profiles and Meas II has one profile. These
five profiles are supported in the RET 54_. In addition, there are twelve more private
class 2 ASDU frames defined. The user can choose which one of these twelve
measurand sets to use. The measurand set number (1...17) can be adjusted via the
"Frame type" parameter.
RTD card's measurand can be transmitted on its own frame. If RTD data frame
parameter is set to one, every other class 2 data is a RTD data frame. The alternate
frame is RTD data frame and the another one is normal user selectable data frame.

Class 2 value scaling

The IEC 60870-5-103 standard defines the scale (max range) of the measurements
to be either 1.2 or 2.4 times the rated value for the measurement. The selection
between the 1.2 scaling or the 2.4 scaling can be done via the "Scale factor"
parameter. In the RET menu values are 0 = 1.2 and 1 = 2.4.

Default mappings

Explanations to Table 9.6.-1:
Status
St
A According to the IEC 60870-5-103 standard
B According to "Digitale Stationsleittechnik - Ergänzende Empfehlungen zur
Anwendung in Verteilnetzstationen"
P Private definition
Function type
Ftyp Note: If stated as *), the signal type Ftyp corresponds with the unit function type.
Unit function type may be adjusted via the "Function type" parameter.
InfNum Information element number
General interrogation
GI 0 = Not in interrogation
1 = Interrogable
TypeId
Typ
Cause of transmission values
COT
1 Spontaneous
9 Interrogated
1MRS755225