ABB REG670 - Identification; Functionality; Four Step Directional Negative Phase Sequence Overcurrent Protection NS4 PTOC

Function Range or value Accuracy
Real part of source Z used for
current polarization
(0.50-1000.00) W/phase
-
Imaginary part of source Z used
for current polarization
(0.50–3000.00) W/phase
-
Operate time, start function at 0 to
2 x I
set
Min 18 ms
Max 28 ms
-
Reset time, start function at 2 to 0
x I
set
Min 18 ms
Max 28 ms
-
Critical impulse time 10 ms typically at 0 to 2 x I
set
-
Impulse margin time 15 ms typically -
8.5 Four step directional negative phase sequence
overcurrent protection NS4PTOC
8.5.1 Identification
Function description
IEC 61850
identification
IEC 60617 identification ANSI/IEEE C37.2
device number
Four step negative sequence
overcurrent protection
NS4PTOC
I2
4
4
alt
IEC10000053 V1 EN
46I2
8.5.2 Functionality
Four step negative sequence overcurrent protection (NS4PTOC) has an inverse or
definite time delay independent for each step separately.
All IEC and ANSI time delayed characteristics are available together with an optional
user defined characteristic.
The directional function is voltage polarized.
NS4PTOC can be set directional or non-directional independently for each of the
steps.
NS4PTOC can be used as main protection for unsymmetrical fault; phase-phase short
circuits, phase-phase-earth short circuits and single phase earth faults.
NS4PTOC can also be used to provide a system backup for example, in the case of the
primary protection being out of service due to communication or voltage transformer
circuit failure.
Section 8 1MRK502052-UEN B
Current protection
374
Technical manual