Gentec
 

Products and services

Capacitor Banks

Unbalance Protection Current Relays

NPR Series

Asymmetrical Relay Protection for Shunt Capacitor Bank Applications

The protection relay for the capacitor bank (NPR series) monitors the three-phase capacitor banks in medium-voltage reactive power compensation systems.

It can recognize various hazardous situations in capacitor units:

  •  overload through overcurrent
  •  overvoltage
  •  asymmetrical load in a double star coupling
  •  overload through harmonics

The NPR reading system captures the ranges and waveforms of currents and voltages linked to inputs.

  • Supply voltage:
    • 99 to 121 VAC, 198 to 253 VAC,
  • Voltage reading: over/under-voltage: 55 to 95 V, 318 to 550 V, 45 to 65 Hz, 
    PT ratio: 1:4000

Asymmetrical (NPR-V): 0 to 20 V, 45 to 65 Hz

  • Current reading (4): 0 to 5 A, minimum sensitivity: 25 mA, load: 15 mΩ
    CT ratio: 1:10,000
  • Relay outputs: 4 N.O., no voltage
  • Opening: 250 VAC at 5 A, 30 VDC at 5 A (ohmic) 110 VDC at 0.4 A (ohmic), 110 VDC at 0.03 A (inductive); output relays can be set individually
  • Interface: Interface and service + RS485 with Modbus protocol (optional)
  • Overvoltage category: II, Level of pollution: 3 (CEI 60664-1)
  • Standards: CEI 60664-1, CEI 61010-1, CEI 61326
  • Compliance: CE, UL, ULC