ABB RED650, Technical Manual, Page: 293 / 926

11.2.2 Functionality
SEMOD113820-4 v12
The aim of the fuse failure supervision function (FUFSPVC) is to block voltage
measuring functions at failures in the secondary circuits between the voltage
transformer and the IED in order to avoid inadvertent operations that otherwise
might occur.
The fuse failure supervision function basically has three different detection
methods, negative sequence and zero sequence based detection and an additional
delta voltage and delta current detection.
The negative sequence detection algorithm is recommended for IEDs used in
isolated or high-impedance earthed networks. It is based on the negative-sequence
quantities.
The zero sequence detection is recommended for IEDs used in directly or low
impedance earthed networks. It is based on the zero sequence measuring quantities.
The selection of different operation modes is possible by a setting parameter in
order to take into account the particular earthing of the network.
A criterion based on delta current and delta voltage measurements can be added to
the fuse failure supervision function in order to detect a three phase fuse failure,
which in practice is more associated with voltage transformer switching during
station operations.
11.2.3 Function block
M13678-3 v9
FUFSPVC
I3P*
U3P*
BLOCK
CBCLOSED
MCBOP
DISCPOS
BLKTRIP BLKZ
BLKU
3PH
DLD1PH
DLD3PH
STDI
STDIL1
STDIL2
STDIL3
STDU
STDUL1
STDUL2
STDUL3
IEC14000065-1-en.vsd
IEC14000065 V1 EN-US
Figure 136: FUFSPVC function block
1MRK 505 394-UEN A
Section 11
Secondary system supervision
Line differential protection RED650 2.2 IEC 287
Technical manual