ABB REL650 series Technical Manual page 187

1MRK 506 335-UUS A
Technical manual
The tP1 timer in figure 84
as fast as the later swings are. The tP2 timer become activated for the detection of the
consecutive swings, if the measured impedance exit the operate area and returns within the
time delay, set on the tW waiting timer. The upper part of figure
ZOUT_A, ZIN_A, AND-gates and tP-timers) are duplicated for phase B and C. All tP1
and tP2 timers in the figure have the same settings.
ZOUTA
AND
ZINA
OR
ZOUTB
ZOUTC
detected
0
0-tW
ANSI05000113 V2 EN
Figure 84: Detection of power swing in phase A
serve as detection of initial power swings, which are usually not
0-tP1
OR
0
-loop
0-tP2
AND
0
AND
Section 6
Impedance protection
84 (internal input signal
-loop
OR DET-A
AND
ANSI05000113-2-en.vsd
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