ABB Relion 670 Series Technical Reference Manual page 588

Section 10
Multipurpose protection
Bin input: BLKUC1TR
Selected current
PickupCurr_UC1
Operation_UC1=On
Bin input: BLKUC1
ANSI05000750 V1 EN
Figure 296: Simplified internal logic diagram for built-in first undercurrent step that is, UC1 (step UC2 has the
same internal logic)
Selected voltage
PickupVolt_OV1
Operation_OV1=On
BLKOV1
ANSI05000751 V1 EN
Figure 297: Simplified internal logic diagram for built-in first overvoltage step OV1 (step OV2 has the same
internal logic)
582
a
b>a
b
AND
DEF time
selected
a
a>b
b
AND
Inverse time
selected
AND
0-DEF
0
0-DEF
0
OR
Inverse
1MRK505222-UUS C
TRUC1
en05000750_ansi.vsd
BLKTROV1
TROV1
AND
PU_OV1
en05000751_ansi.vsd
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