Seg WIC1 - I2> - Negative-Sequence Current Protection [51 Q]

4.7 I2> – Negative-Sequence Current Protection [51Q]
The protection function »I2>« is similar to the Phase Overcurrent protection. The main
di󰊞erence is that the Phase Overcurrent protection monitors the three phase currents,
whereas the »I2>« module monitors the negative-sequence current I2.
• IEEE C37.2 / ANSI 51Q — Negative-Sequence Current Protection,•
available characteristics see ╚═▷ “11.2.3 Characteristics »I2>«”.
For general information about the concept of WIC1 protection functions, see ╚═▷
“4.1 »Prot« – General Protection Module”.
NOTICE!
High inrush currents can lead to a transient saturation of the phase CTs. When this
happens during a transformer inrush the determination of (positive and negative)
sequence currents yields incorrect results.
156 WIC1 WIC1-1.0-EN-MAN
4 Protective Elements
4.7 I2> – Negative-Sequence Current Protection [51Q]