Operation Principle - ABB REL650 series Technical Manual

1MRK 506 335-UUS A
Table 63: ZMRPSB (68) Group settings (advanced)
Name Values (Range)
tP1 0.000 - 60.000
tP2 0.000 - 60.000
tW 0.000 - 60.000
tH 0.000 - 60.000
tR1 0.000 - 60.000
tR2 0.000 - 60.000
Table 64: ZMRPSB (68) Non group settings (basic)
Name Values (Range)
GlobalBaseSel 1 - 6
6.7.6
Technical manual
Unit Step
s 0.001
s 0.001
s 0.001
s 0.001
s 0.001
s 0.001
Unit Step
- 1

Operation principle

Power swing detection (ZMRPSB ,68) function comprises an inner and an outer
quadrilateral measurement characteristic with load encroachment, as shown in figure 83.
Its principle of operation is based on the measurement of the time it takes for a power
swing transient impedance to pass through the impedance area between the outer and the
inner characteristics. Power swings are identified by transition times longer than a
transition time set on corresponding timers. The impedance measuring principle is the
same as that used for the distance protection zones. The impedance and the characteristic
passing times are measured in all three phases separately.
Default Description
0.045 Timer for detection of initial power swing
0.015 Timer for detection of subsequent power
swings
0.250 Waiting timer for activation of tP2 timer
0.500 Timer for holding power swing PICKUP output
0.300 Timer giving delay to inhibit by the residual
current
2.000 Timer giving delay to inhibit at very slow swing
Default Description
1 Selection of one of the Global Base Value
groups
Section 6
Impedance protection
177