ABB Relion 670 Series Applications Manual page 268

Section 10
Unbalance protection
140
120
100
80
60
40
20
0
IEC19000728 V1 EN-US
Figure 126: Differential voltage variation with number of units failure for considered
Table 45: Parameter and setting values for the ungrounded capacitor bank
Name
SCBGndType
NeutVoltMeas
UMin>
VoltRatioL1
VoltRatioL2
VoltRatioL3
URatioVar>
UdifWrn>
tDefWrn
UdifAlm>
tDefAlm
Udif>
BlockTrip
CurveType
tDefTrip
tMin
tReset
k
tPCrv
tACrv
tBCrv
tCCrv
tDCrv
CrvSat
262
Trip
Alarm
Warning
27.1429
16.8478
12.2159
7.8824
3.8187
0
1 2
3 4 6
ungrounded capacitor bank
© Copyright 2017 Hitachi Power Grids. All rights reserved
70
53.1674
39.0977
8 10
12
Number of units failure
Default value
Ungrounded
Available
50.0% of UBase
0.50
0.50
0.50
10.00
3% of UBase
5.00
7% of UBase
5.00
10% UBase
Trip enabled
Programmable
5.00
0.10
0.02
0.05
1.000
1.000
1.00
0.0
0.000
0
1MRK 511 401-UEN Rev. K
131.9737
116.3636
90.5594
14 16
18
IEC19000728-1-en.vsdx
Bay control REC670
Application manual