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CEX Angle Impedance Relay

CEX Angle Impedance Relay

The Type CEX57 is a family of high-speed induction cup relays with angle impedance characteristics that can be set parallel to the impedance characteristic of a protected line. Generally, these relays are meant to be used with other pro-tective relays in blinder applications restrict the tripping zone of a scheme they may be used in applications that require tripping for out-of-step conditions. These are a single-phase relays that includes two ohm units with opposite polarity and may also include an auxiliary telephone type unit.

The Type GSY51 relay includes a mho distance unit with reverse offset, six auxiliary telephone units and a target-seal in unit all mounted in one drawout case. This relay is intended for use with the CEX57E angle impedance relay to provide out-of-step protection for a generator.

End of life notice: The CEX has been discontinued as of October 1, 2013.
Read full notice.

  • Line blinder applications (CEX57D or CEX57F)
  • Line out-of-step tripping (CEX57E/NAA19B)
  • Protection and Control
  • Angle impedance in out-of-step tripping schemes