NARI NSR621RF-D Capacitor Protection and Control Device

The NSR621RF-D is an integrated capacitor protection and control device that provides protection, monitoring, control, and operation functions for capacitors.
For capacitors with different wiring configurations, the corresponding protection and control devices are divided into three models:
NSR621RF-DA is suitable for small current grounding systems (neutral point ungrounded or grounded via arc suppression coil) and neutral point grounded via resistor systems at voltage levels below 110kV, used for the protection and control of Y or Δ connected shunt capacitor banks (only Type A includes unbalanced voltage or zero-sequence differential voltage protection, and unbalanced current or zero-sequence differential current protection).
NSR621RF-DC is suitable for non-directly grounded systems or small resistance grounded systems at voltage levels below 110kV, used for the protection and control of bridge-connected shunt capacitor banks (only Type C includes capacitor bridge differential protection).
NSR621RF-DD is suitable for non-directly grounded systems or small resistance grounded systems at voltage levels below 110kV, used for the protection and control of bridge-connected shunt capacitor banks (only Type D includes capacitor phase-separated differential voltage protection).

1 Function Configuration

Main protection functions include:

1) Two-stage overcurrent protection (**instantaneous overcurrent, definite-time overcurrent);

2) Definite-time overvoltage protection;

3) Current-blocked undervoltage protection;

4) Two-stage zero-sequence overcurrent protection;

5) External non-electrical quantity input protection;

6) Unbalanced voltage or zero-sequence differential voltage protection (only NSR621RF-DA has);

7) Unbalanced current or zero-sequence differential current protection (only NSR621RF-DA has);

8) Capacitor bridge differential protection (only NSR621RF-DC has);

9) Capacitor phase-separated differential voltage protection (only NSR621RF-DD has).

Main monitoring and control functions include:

1) Collection of 23 remote signaling inputs, device remote signaling status change, SOE recording;

2) Remote control of circuit breaker opening and closing under normal conditions;

3) 19 telemetry quantities including Ia, Ib, Ic, Ua, Ub, Uc, 3Io, Uab, Ubc, Uca, 3Uo, Pa, Pb, Q, S, φ, Fr;

4) Event SOE; 5) Operation waveform recording.