ABB RET670 Installation And Commissioning Manual page 166

Section 13
Verifying settings by secondary injection
160
UL1
UL2
UL3
UN
IEC07000106 V2 EN
Figure 63: Connection of the test set to the IED for test of U1 block level
where:
1 is three-phase voltage group1 (U1)
2 is three-phase voltage group2 (U2)
3. Decrease slowly the voltage in phase UL1 of the test set until the START
signal resets.
4. Check U1 blocking level by comparing the voltage level at reset with the set
undervoltage blocking U1Low.
5. Repeat steps 2 to 4
The connections to U1 must be shifted to test another phase.
(UL1 to UL2, UL2 to UL3, UL3 to UL1)
U2Low
Check of
Procedure
1. Connect voltages to the IED according to valid connection diagram and
figure 64.
to check U1Low for the other phases.
1MRK 504 088-UEN C
UL1
UL2
1
UL3
UN
UL1
2
UL2
UL3
IEC07000106-1-en.vsd
Installation and commissioning manual