Negative Phase Sequence Overcurrent (46Nps); Figure 2-11 Negative Phase Sequence Overcurrent - Siemens 7SR21 Manual

2.10

Negative Phase Sequence Overcurrent (46NPS)

Voltage Inputs:
Current Inputs:
Disable:
Map Pickup LED:
Where two NPS elements are being used with different settings, it is convenient to test the elements with the
highest settings first. The elements with lower settings can then be tested without disabling the lower settings.
The Thermal withstand limitations of the current inputs, stated in the Performance Specification should always be
observed throughout testing.
NPS Overcurrent can be tested using a normal 3P balanced source. Two phase current connections should be
reversed so that the applied balanced 3P current is Negative Phase Sequence.
©2010 Siemens Protection Devices Limited

Figure 2-11 Negative Phase Sequence Overcurrent

n/a
I (I ), I (I ), I (I ),
L1 A L2 B L3 C
51, 51V, 51C, 37, 49, 50CBF, 60CTS, 46BC
46IT/46DT - Self Reset
7SR21 & 7SR22 Argus Commissioning and Maintenance
Chapter 6 Page 39 of 69