Check Of Voltage Differential Trip And Alarm Levels - Hitachi RET670 Commissioning Manual

Section 11
Testing functionality by secondary injection
IEC07000107 V2 EN-US
Figure 52:
where:
1
2
2. Apply voltage higher than the highest set value of UDTrip, U1Low and U2Low to the U1 three-
phase inputs and to one phase of the U2 inputs according to figure 52.
The voltage differential START signal is set.
3. Decrease slowly the voltage in phase UL3 of the test set until the START signal resets.
4. Check U2 blocking level by comparing the voltage level at reset with the set undervoltage
blocking U2Low.
11.6.5.3

Check of voltage differential trip and alarm levels

Procedure
1. Connect voltages to the IED according to valid connection diagram and figure 53.
200
UL1
UL2
UL3
UN
Connection of the test set to the IED for test of U2 block level
is three-phase voltage group1 (U1)
is three-phase voltage group2 (U2)
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UL1
UL2
1
UL3
UN
UL1
2
UL2
UL3
IEC07000107-1-en.vsd
Transformer protection RET670
1MRK 504 165-UEN Rev. K
SEMOD175258-104 v3
Commissioning manual