Figure 27: Directional trip angles
For close up thr
ee-phase faults, all three voltages will collapse to zero and no healthy phase voltages will be
present. For this reason, the device includes a synchronous polarisation feature that stores the pre-fault voltage
information and continues to apply this to the directional overcurrent elements for a time period of 3.2 seconds.
This ensures that either instantaneous or time-delayed directional overcurrent elements will be allowed to operate,
even with a three-phase voltage collapse.
P24xM Chapter 6 - Current Protection Functions
P24xM-TM-EN-2.1 97
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