Differential Protection Values; Measured Values Of The Differential Protection; Information List; Constellation Measured Values - Siemens SIPROTEC 7SD80 Manual

Functions
2.17 Additional Functions
2.17.4

Differential Protection Values

2.17.4.1 Measured Values of the Differential Protection

The differential and restraint current values of the differential protection can be displayed at the front of the
device, read out via the operating interface using a PC with DIGSI, or transferred to a control center via the
system interface.
Table 2-11 Measured values of the differential protection
„Diff3I0="
„Rest3I0="

2.17.4.2 Information List

No. Information
7748 Diff3I0=
32226 Rest3I0=
2.17.5

Constellation Measured Values

2.17.5.1 Description

The measured values of the constellation of both possible devices are shown here by evaluating the device
(see table 2-12). Information on the second device is given in the Appendix.
The computation of this measured values constellation is also executed during an existent system fault in an
interval of approx. 0.5 s.
The current/voltage measured locally is assumed as reference value for the angle. The angle values of the
remote ends are referred to the locally measured value.
Examples for the current in a constellation with 2 ends:
Current IA at the local end 98 % angle 0°
Current IA at the local end 98 % angle 180°
The device addresses allow differentiating the devices. This procedure allows current transformer polarity re-
versal to be detected immediately and the line angle (if voltages are available) to be read.
206
Measured Values
Calculated restraint currents of the zero sequence system
Calculated differential current of the zero sequence system
Type of In-
formation
MV
MV
Comments
Diff3I0 (Differential current 3I0)
Rest3I0(% Operational nominal current)
E50417-G1140-C474-A1, Release date 09.2011
referred to
% rated operational current
I/InO
SIPROTEC, 7SD80, Manual