Description

KCC112x

AC GENERATOR CURRENT DIFFERENTIAL PROTECTION

• • • Generator stator earth fault protection

    • Winding Insulation Protection

    • Up to two individual very fast analogue output signals
      (<50mS), (optional)

    • The Pathfinder eases fault finding

    • For use with 1A or 5A current transformers

    • DIN96 Slave Indicator (Scaled 0-40%In) with status LED’s (Optional)

    • Up to two individual very fast analog output signals (<50mS)< (Optional)

Description
KCC112E, KCC112G, KCC112Fx or KCC112GFx protects against phase-, earth- and winding faults within the protected area (the stator) of large AC generators. It detects even minute insulation punctures, flash-over carbon deposits and contamination. The unit measures highest up differential current from anti-paralleled CTs in a Merz-Price configuration, by comparing current levels at the end of each phase winding.

R1 is used for early warning. R2 or R3 (fail safe) is to be used for generator breaker trip, the “other” alarm relay can be used for local indication input to PMS, alarm system etc.

Alarm trip must be set sufficiently high to ensure that generator magnetization current does not cause tripping. The alarm delay is to be set so that the initial inrush current have returned to normal level before the delay period elapses. The warning trip level and delay can be set as required to give early warning.

User settable trip levels and delays. Color of LEDs indicates alarm status. LEDs flash during count-down. The meter and the triple-zone status LEDs at a glance gives the clear safety message:

• ALARM
• WARNING
• NORMAL

The F-versions have an fast response mA output signal proportional to highest up current.  Up to two individual very fast analog output signals (optional) proportional to the highest up current.  The analog output is isolated from the CT’s and the auxiliary power.

The “Pathfinder” function identifies the phase(s) causing the trip by the flashing pattern of the relevant LED(s).