NA11 FEEDER PROTECTION RELAY THE BASIC SOLUTION FOR FEEDERS AND TRANSFORMERS PROTECTION WITH AUTOMATIC RECLOSURE
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Protection Relays FEEDER PROTECTION RELAY THE BASIC SOLUTION FOR FEEDERS AND TRANSFORMERS PROTECTION WITH AUTOMATIC RECLOSURE — Application The relay type NA11 can be used in radial networks as feeder or power transformer protection. In solidly grounded systems the residual overcurrent protection can be used on feeders of any length, while in ungrounded or Petersen coil and/or resistance grounded systems, the residual overcurrent protection can be used on feeders of small length in order to avoid unwanted trippings due to the capacitive current contribution of the feeder on external ground fault. Beside to the phase and residual overcurrent protections, the automatic reclosing function is provided. The NA11 protection relay may be shipped with traditional CTs or low power (LPCT) current inputs. - Protective & control functions Alternative Control functions METERING - I L1..I L3,I E - Oscillography - Events & Faults log COMMUNICATION - USB - Modbus RS485 - Modbus TCP/IP - IEC 870-5-103/DNP3 Phase overcurrent Residual overcurrent Breaker failure CT supervision Trip circuit supervision Automatic reclosure

— Measuring inputs • Three phase current inputs and one residual current input, with nominal currents independently selectable at 1 A or 5 A through DIP-switches for CTs interface • Three phase current inputs for low power current sensors (LPCT); the residual current is calculated from the vectorial sum of the three phase currents. This new sensors have reduced cost, reduced weight, reduced wiring cost and best transient performances compared with traditional CTs. Moreover, external shorting devices are not required and safety is highly-improved. The user interface comprises a membrane...

Several predefined functions are implemented: • Activation of two set point profiles • Phase CTs monitoring (74CT) • Logic selectivity • Cold load pickup (CLP) with block or setting change • Trip circuit supervision (74TCS) • Second harmonic restraint (inrush) • Remote tripping • Synchronization • Circuit Breaker commands and diagnostic • Automatic reclosing Moreover user defined logic must be customized in accordance with IEC 61131-3 protocol by means programmable logic controller (PLC). Circuit Breaker Several diagnostic, monitoring and control functions are provided: • Health thresholds...

SPECIF ICAT IONS INPUT CIRCUITS GENERAL — Mechanical data Mounting: flush, projecting, rack or separated operator panel Mass (flush mounting case) 2.0 kg — Insulation tests Reference standards High voltage test 50Hz Impulse voltage withstand (1.2/50 ms) Insulation resistance — Voltage dip and interruption Reference standards — EMC tests for interference immunity 1 MHz damped oscillatory wave Electrostatic discharge Fast transient burst (5/50 ns) Conducted radio-frequency fields Radiated radio-frequency fields High energy pulse Magnetic field 50 Hz Damped oscillatory wave Ring wave Conducted...

GENERAL SETTINGS — Rated values Relay nominal frequency f n Traditional CTs: • Relay phase nominal current In • Phase CTs nominal primary current Inp • Relay residual nominal current IEn • Residual CT nominal primary current IEnp Low power CTs: • Nominal primary current I np — Binary input timers ON delay time (IN1 tON, IN2 tON, ...IN5 tON) 0.00...100.0 s OFF delay time (IN1 tOFF, IN2 tOF,...IN5 tOFF) 0.00...100.0 s Logic Active-ON/Active-OFF — Relay output timers Minimum pulse width PROTECTIVE FUNCTIONS — Thermal protection with RTD thermometric probes - 26 Alarm • Alarm threshold qALx...

IE>> Element • IECLP >> Activation time (t ECLP>>) 0.00...100.0 s • IE>> Reset time delay (t E>> RES) 0.00...100.0 s Definite time • 50N/51N Second threshold definite time (IE>>def) 0.100...35.0 In • IE>>def within CLP (IECLP>>def ) 0.100...35.0 In • IE>>def Operating time (t E>> def ) 0.03...10.00 s IE>>> Element • IECLP >>> Activation time (t ECLP>>>) 0.00...100.0 s • IECLP >>> Reset time delay (t E>>> RES) 0.00...100.0 s Definite time • 50N/51N Third threshold definite time (I E>>>def) 0.100...35.0 In • IECLP >>> def within CLP (IECLP>>>def ) 0.100...35.0 In IECLP >>> def Operating time...

— Digital Fault Recorder (DFR) File format COMTRADE Records depending on setting [1] Recording mode circular Sampling rate 24 samples per cycle Trigger setup: • Pre-trigger time 0.05...1.00 s • Post-trigger time 0.05...60.00 s • Trigger from inputs IN1, IN2...INx • Trigger from outputs K1...K6...K10 • Manual trigger ThyVisor Set sample channels: • Instantaneous phase currents i L1, i L2, i L3 • Instantaneous residual current (CTs) iE — Connection diagram example Set analog channels (Analog 1...12): • Frequency f • Fundamental RMS phase currents I L1, I L 2 , I L 3 • Fundamental RMS of...

DIMENSIONS FRONT VIEW PROJECTING MOUNTING FLUSH MOUNTING FLUSH MOUNTING (standard CT inputs) FLUSH MOUNTING (LPCT inputs) FLUSH MOUNTING SEPARATE OPERATOR PANEL PROJECTING MOUNTING (Separate operator panel) RACK MOUNTING PROJECTING MOUNTING (Stand alone) FLUSH MOUNTING CUTOUT START TRIP