Voltage Protection: Nps Overvoltage (47) - 7Sr1705/6; Figure 3-21 Logic Diagram: Nps Overvoltage Protection (47) - Siemens 7SR17 Rho Manual

Chapter 1) 7SR17 Rho Description Of Operation
3.8 V P : NPS O (47) - 7SR1705/6
OLTAGE ROTECTION VERVOLTAGE
Negative phase sequence (NPS) voltage (V2) is a measure of the quantity of unbalanced voltage in the system.
The relay derives the NPS voltage from the three input voltages (VL1, VL2 and VL3).
Two elements are provided.
47-n Setting sets the pick-up voltage level for the element.
The 47-n Hysteresis setting allows the user to vary the pick-up/drop-off ratio for the element.
An output is given after elapse of the 47-n Delay setting.
Operation of the negative phase sequence voltage elements can be inhibited from:
Inhibit 47-n A binary or virtual input.
Figure 3-21 Logic Diagram: NPS Overvoltage Protection (47)
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