ABB HU Instruction Leaflet page 9

Figure 10. Differential Voltage Characteristic of the DU
Unit of the HU and HU-1 Relays with a pickup
of 0.30 times tap.
Figure 12. Typical Tripping Time Characteristic.
Sub 3
471132
Figure 11. Differential voltage Characteristic of the DU
Unit of the HU and HU-1 Relays with a pickup
of 0.35 times tap.
Sub 1
538029
Figure 13. Typical Frequency Response of the HU and
HU-1 60 hertz relays.
41-347.12C
Sub 1
471135
Sub 2
471052
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