Hitachi RET670 Commissioning Manual page 222

Section 11
Testing functionality by secondary injection
•
•
•
2. Activate the RESETCOMP input to ensure that the stored values of the compensation factors
are reset to zero.
3. The logical signals and service values for SCUVPTOV function are available on the local HMI
under: Main menu/Tests/Function status/Unbalance protection/
CapBankVoltageUnbalance(60V, Uub>)/SCUVPTOV(60V, Uub>):x, where x = instance
number.
4. To store the new values of compensation factors, perform the following steps:
Step No.
4-a
4-b
4-c
* - VT ratios of phase voltages and neutral voltages are considered as 400 kV/110 V. The value of
UBase is considered as 110 V.
The voltage inputs U
input.
5. Check the respective operation of warning, alarm, and trip.
216
UNUnbalAlm> = 2.5% UBase
UNUnbalWrn> = 1.0% UBase
UMin> = 75% UBase
Changes after step 2
Inject constant voltages* of U
63.5∠0° V, U = 63.5∠240° V,
L2
U = 63.5∠120° V,
L3
and U = 0∠0° V in secondary at
N
rated frequency.
Change U = 2∠0° V in
N
secondary at rated frequency
Activate binary input TRIGCOMP
for 1 s
, U , and U
L1 L2
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Expected Output
= UL1, UL2, and UL3 = 230.909 kV
L1
UNSCB = 0.000 kV
UNUNBAL = 0.000 kV
PUNUNBAL= 0.000 %
The following outputs should show the mentioned
values:
• K1USED = 0.000
• K2USED = 0.000
• K1MON = 0.000
• K2MON = 0.000
UL1, UL2, and UL3 = 230.909 kV
UNSCB = 7.273 kV
UNUNBAL = 7.273 kV
PUNUNBAL = 3.151 %
The following outputs should show the mentioned
values:
• K1USED = 0.000
• K2USED = 0.000
• K1MON = 0.030
• K2MON = 0.030
UL1, UL2, and UL3 = 230.909 kV
UNSCB = 7.273 kV
UNUNBAL = 0.000 kV
PUNUNBAL= 0.000 %
• The output COMPEXED should become
HIGH for 100 ms
• The output LASTCOMP should display the
date and time of compensation.
The following outputs should show the mentioned
values:
• K1USED = 0.030
• K2USED = 0.030
• K1MON = 0.030
• K2MON = 0.030
refer to the bus voltages and U
L3
1MRK 504 165-UEN Rev. K
refers to the neutral voltage
N
Transformer protection RET670
Commissioning manual