ABB Relion 670 Series Applications Manual page 257

1MRK 511 401-UEN Rev. K
U
L1
IEC19000653 V1 EN-US
Figure 120: Ungrounded double WYE connected SCB
Where,
U is the neutral voltage of the SCB.
N
10.3.3 Setting guidelines
Setting procedure on the IED
The parameters for the phase voltage differential based capacitor bank protection function
SCPDPTOV are set through the local HMI or Protection and Control Manager (PCM600).
Common base IED values for the primary voltage (UBase) set in the global base values for the
settings function GBASVAL.
GlobalBaseSel : This is used to select the base value (UBase) for the voltages from the GBSVAL
function.
Operation : Set the phase voltage differential based capacitor bank protection function to On /
Off .
SCBGndType : This parameter setting can be set to either Grounded or Ungrounded .
• If the parameter setting is set to
• If the parameter setting is set to
either from measurement or zero sequence component of bus voltage.
NeutVoltMeas : This parameter setting can be set to either Available or Not available .
• If the parameter setting is set to
capacitor bank is used for calculation of differential voltage.
• If the parameter setting is set to
bus voltage is used as the neutral voltage for calculation of differential voltage.
Bay control REC670
Application manual
L1
L2
L3
C C
C
Tap
C C
C
C
C C
C C
C
U
TapL1_L
N
© Copyright 2017 Hitachi Power Grids. All rights reserved
C
C C
C
C C
C
C
C
C C
C
N
U
N
Grounded , then the neutral voltage is considered as zero.
Ungrounded , then the neutral voltage is considered
Available , then the measured neutral voltage from the
Not available , then the zero sequence component of the
Section 10
Unbalance protection
Tap
U
TapL1_R
IEC19000653-1-en.vsdx
GUID-9F66B90F-2C99-4951-8FDB-94FCF2E81A90 v1
GUID-1DB019F3-78CD-488B-9B4B-01A741E01BD3 v1
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