11.2.6 Monitored data
PID-3492-MONITOREDDATA v8
Table 161: FUFSPVC Monitored data
Name
Type Values (Range) Unit Description
3I0 REAL - A Magnitude of zero
sequence current
3I2 REAL - A Magnitude of negative
sequence current
3U0 REAL - kV Magnitude of zero
sequence voltage
3U2 REAL - kV Magnitude of negative
sequence voltage
11.2.7 Operation principle
11.2.7.1 Zero and negative sequence detection
M13677-3 v5
The zero and negative sequence function continuously measures the currents and
voltages in all three phases and calculates, see figure 137:
• the zero-sequence voltage 3U0
• the zero-sequence current 3I0
• the negative sequence current 3I2
• the negative sequence voltage 3U2
The measured signals are compared with their respective set values 3U0> and
3I0<, 3U2> and 3I2<.
The function enable the internal signal FuseFailDetZeroSeq if the measured zero-
sequence voltage is higher than the set value 3U0> and the measured zero-
sequence current is below the set value 3I0<.
The function enable the internal signal FuseFailDetNegSeq if the measured
negative sequence voltage is higher than the set value 3U2> and the measured
negative sequence current is below the set value 3I2<.
A drop out delay of 100 ms for the measured zero-sequence and negative sequence
current will prevent a false fuse failure detection at un-equal breaker opening at the
two line ends.
Section 11 1MRK 505 394-UEN A
Secondary system supervision
290 Line differential protection RED650 2.2 IEC
Technical manual