11.5.18.2 Verifying the settings
GUID-3A2B7FF5-330E-4A0D-AB74-EBAE6258C176 v1
Verifying settings by secondary injection
GUID-39632D30-A8D8-417D-985C-8F886106783E v4
1. Connect the test set for three-phase current injection and three-phase voltage injection to the
appropriate IED terminals.
2. Go to Main menu /Settings /IED Settings /Current protection /VoltageRestOverCurr ( 51V,2(I>/
V<))/VRPVOC (51V,2(I>/V<)):1 /General and make sure that the function is enabled, that is,
Operation is set to Enabled.
3. The test of the function may be performed by injecting restrain voltage and increasing the injected
current(s). Note the value at which the PICKUP and STOC signals are set.
In the following equations, restrain voltage is the magnitude of the minimum phase-
to-phase voltage in secondary volts.
The set trip value in secondary amperes is calculated according to the following equations:
First part of the characteristic (Restrain voltage ≤ 25% of VBase):
Picup Curr
IBase
CT
CTprim
VDepFact_ sec
100 100
× × ×
ANSI13000291 V1 EN-US (Equation 95)
Second part of the characteristic (25% of VBase ≤ Restrain voltage ≤ VHighLimit/100*VBase), valid
when setting parameter VDepMode = Slope:
Pickup Curr
IBase
CT
CTprim
VDepFact_ sec
100
1
100
× ×
× −
VVHighLimit
VBase
VT
VTprim
strainVoltage
−
( )
× ×
× −
25
100
25
10sec
Re
00 100
× ×
+ ×VBase
VT
VTprim
Pickup Curr
IB
sec _
aase
CT
CTprim
VDepFact
× ×
sec
100
ANSIEQUATION2433 V2 EN-US (Equation 96)
Third part of the characteristic (VHighLimit/100*VBase ≤ Restrain voltage):
Picup Curr
IBase
CT
CTprim
_ sec
100
× ×
ANSIEQUATION2434 V1 EN-US (Equation 97)
Example (rated secondary current = 5A):
CT ratio
10 000/5A
VT ratio 10 kV/100 V
Pickup_Curr 100%
VDepFact 25%
VHighLimit 100%
IBase 10 000 A
VBase 10 kV
A test for each section of the characteristic of the function VRPVOC may be performed; that may
be achieved by applying the following voltages:
First section of the characteristic:
Section 11 1MRK 504 165-UUS Rev. J
Testing functionality by secondary injection
198 Transformer protection RET670
Commissioning manual
© 2017 - 2021 Hitachi Power Grids. All rights reserved
To Next Page
Loading...
