The function enable the internal signal FuseFailDetZeroSeq if the measured zero-
sequence voltage is higher than the set value
3V0PU
and the measured zero-sequence
current is below the set value
3I0PU
.
The function enable the internal signal FuseFailDetNegSeq if the measured negative
sequence voltage is higher than the set value
3V2PU
and the measured negative
sequence current is below the set value
3I2PU
.
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.
IA
IB
IC
Zero
sequence
filter
Negative
sequence
filter
VA
VB
VC
Zero
sequence
filter
Negative
sequence
filter
CurrZeroSeq
CurrNegSeq
a
b
a>b
a
b
a>b
a
b
a>b
a
b
a>b
3I0PU
3I2PU
VoltZeroSeq
VoltNegSeq
AND
AND
FuseFailDetZeroSeq
FuseFailDetNegSeq
Sequence Detection
3V0PU
3V2PU
3I0
3I2
3V0
3V2
ANSI10000036-2-en.vsd
0
100 ms
0
100 ms
ANSI10000036 V2 EN
Figure 303:
Simplified logic diagram for sequence detection part
The calculated values 3V0, 3I0, 3I2 and 3V2 are available as service values on local
HMI and monitoring tool in PCM600.
Input and output signals
The output signals 3PH, BLKV and BLKZ can be blocked in the following conditions:
Section 11
1MRK505222-UUS C
Secondary system supervision
602
Technical reference manual
Summary of Contents for Relion 670 series
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