GE PACSystems RX3i User Manual page 21

GFK-2749
Fast Rotating Phase Angles
For faster rotating phase angles where Angle Delay > (Phase_Shift_Thr - 2º)/2, these
equations apply:
PhaseShiftOK = On @ Angle Delay
PhaseShiftOK = Off @ Angle Delay – Phase_Shift_Thr
Fast Rotation: Angle Delay > (Phase_Shift_Thr - 2º)/2
If a request to sync is on, or received by the PSM module at any time in the green region
(while PhaseShiftOK = on), the CloseRelayOK status bit will be set and the IC694ACC200
output contacts will close.
Once CloseRelayOK is on and the IC694ACC200 output contacts are closed, they remain
on and closed through the green, orange and yellow regions, regardless of grid alarms,
until after the breaker delay plus 24 power line cycles pass, to allow the newly
synchronized grids to settle. After the settling time, all ANSI protections are reinstated and
the PSM monitors the Delta Frequency, Delta Voltage and Phase Shift status bits again.
In the absence of other alarms, the phase angle is allowed to drift within the phase shift
threshold (the yellow region) indefinitely as the PSM waits for the physical contacts to
synchronize the grids.
Chapter 1 PSM Module Description and Specifications
-Phase_Shift_Thr
+Phase_Shift_Thr
0º
15.9º
25.9º
SYNCHROSCOPE
1
1-15