Schneider NT06H2 Air Circuit Breaker

NT: MasterPact NT series interruttore automatico dell'aria (ACB, legacy model, interrotto; replacement model MTZ1 06H2)

06: Dimensioni del telaio 06, frame rated current 630A

H2: Breaking capacity class H2; Icu=50kA@440VAC, short-time withstand current Icw=50kA (1S), Class B selective protection

Parametri elettrici principali

Note chiave

1. Stato di interruzione: NT series scheduled for end-of-sale by the end of 2025. Replacement model MTZ1 06H2, part number LV947203 (draw-out version)
2. Parameter Clarification

Ue=690V: Maximum normal operating voltage

Ui=1000 V: Tensione di tenuta a frequenza industriale

Uimp=12kV: Lightning impulse withstand voltage. NOT applicable for 12kV high-voltage switchgear, this is an insulation index for low-voltage ACB

3. Applicazione: Incoming feeder, bus tie and heavy-load outgoing feeder in low-voltage distribution systems, for industrial plants, data centers and marine power distribution; supports selective protection and coordination with upstream/downstream devices
4. Reference Frame Part Numbers

NT06H2 3P Fixed: 47113

NT06H2 3P Draw-out: 47203

NT06H2 4P Fixed: 47119

Accessori & Pezzi di ricambio

Trip Units: Micrologica 2.0 / 5.0 / 6.0 / 7.0 (sovraccarico, ritardo di breve durata, instantaneous and earth-fault protection)

Accessori: Motor operating mechanism, contatti ausiliari, fault alarm contacts, closing coil, shunt trip coil, interblocco della porta, phase barriers

Draw-out base: Mandatory independent cradle for draw-out version

Linee guida per la risoluzione dei problemi

1. Mancata chiusura: Undervoltage coil de-energized, incomplete spring charging, cradle not in connected position, interlock blocking
2. Unintended tripping: Check trip unit protection curve, guasto a terra, harmonic distortion and temperature rise
3. Prova di isolamento: Power frequency withstand test at Ui=1000V level; 12kV impulse withstand is type-test only, no on-site 12kV impulse test

Domestic Alternative Reference

Domestic MT06H2 (Schneider domestic MT series). Compatible breaking capacity and mounting dimensions for direct replacement.

Schneider MasterPact NT06H2 Air Circuit Breaker Technical Manual (Full Engineering Version, per original datasheet 0613CT0001)

Osservazioni: NT series is legacy discontinued ACB, frame size NT06, In=630A; breaking class H2; frame supplied without trip unit, MicroLogic trip unit to be ordered separately; standard IEC 60947-2, isolating function, Class B selective protection

Sommario

1. Panoramica del prodotto & Spiegazione del codice modello
2. Rated Electrical Parameters
3. Parametri meccanici, Dimensioni complessive & Peso
4. MicroLogic Trip Unit Selection
5. Elenco degli accessori & Secondary Terminal Definition
6. Installazione & Requisiti di cablaggio
7. Operazione, Handling & Interlock Description
8. Manutenzione, Ispezione & Risoluzione dei problemi
9. Condizioni ambientali
10. Replacement Model Information
11. Original Document Index
12. Panoramica del prodotto & Spiegazione del codice modello

1.1 Panoramica

MasterPact NT series low-voltage air circuit breakers for incoming feeders, bus ties and high-current outgoing feeders in 400/690V low-voltage distribution systems. NT06H2 maximum frame rating 630A, available in draw-out or fixed construction, spring charged operation, configurable with intelligent MicroLogic protection unit, supports remote signalling, metering and communication.

Promemoria importante: Ui=1000 V (tensione nominale di isolamento), Uimp=12kV (lightning impulse withstand voltage). NOT 12kV high voltage circuit breaker, only for AC ≤690V low-voltage distribution.

1.2 Ripartizione del modello

NT: MasterPact NT series air circuit breaker

06: Dimensioni del telaio 06, frame rated current 630A

H2: Breaking class H2; Icu=50kA@440VAC, Icw=50kA 1s, Class B selective

Numeri di parte:

NT06H2 3P Fixed: 47113

NT06H2 3P Draw-out: 47203

NT06H2 4P Fixed: 47119

1.3 Stato del prodotto

NT series scheduled end-of-sale by end of 2025; replacement model MTZ1 06H2, part number LV947203 (estrazione). Mounting dimensions and secondary interfaces fully compatible for direct replacement.

2. Rated Electrical Parameters

3. Parametri meccanici, Dimensioni complessive & Peso

3.1 Resistenza meccanica

Vita meccanica: 20,000 operazioni (no-load make/break)

Vita elettrica (400V, In): 10,000 operazioni

Spring charging: Manual charging / motor charging MCH optional

3.2 Dimensioni complessive (3P, unità: mm)

Tipo fisso: W300 × H415 × D266

Tipo estraibile (with cradle): W300 × H415 × D376

4P version width 360mm, height and depth unchanged

3.3 Peso

Fixed frame only: ≈32kg

Draw-out frame + cradle: ≈52kg

3.4 Three positions for draw-out version

1. Connected Position: Main circuit and secondary circuit fully connected, normal operation
2. Test Position: Main circuit disconnected, secondary circuit remains connected for protection test
3. Disconnected Position: Main and secondary circuits fully disconnected, breaker can be withdrawn for maintenance
4. MicroLogic Trip Unit Selection (Deve essere ordinato separatamente, not included with frame)

Protection setting range: E (a lungo) 0.4~1×In; Isd short-time delay 0.5~10×In, delay 0.1/0.2/0.4s; Ii instantaneous 1~15×In.

5. Elenco degli accessori & Secondary Terminal Definition

5.1 Accessori opzionali

1. MCH: Charging motor AC220V / DC24V
2. XF: Closing solenoid AC220V / DC24V
3. MX: Bobina a lancio di corrente (apertura remota)
4. MN: Sganciatore di minima tensione (MNu time-delayed undervoltage for auto-transfer application)
5. DI: Contatti ausiliari (CB on/off status feedback)
6. SDE: Fault trip contacts (signal for overload/short-circuit/earth fault trip)
7. PF: Cradle position contacts (connected / test / disconnected position)
8. Phase barriers, interblocco della porta dell'armadio, mechanical interlock cables, padlock device
9. ULP communication module: Modbus-RTU, remote signalling & misurazione

5.2 Secondary Terminal Definition

6. Installazione & Requisiti di cablaggio
7. Montaggio: Vertical upright installation, ±5° tilt allowed; inverted mounting prohibited
8. Collegamento al circuito principale: Collegamento frontale / rear horizontal / rear vertical connection; apply specified tightening torque for copper busbars to avoid overheating
9. Secondary control wiring: 0.75~1.5mm² multi-core shielded cable; independent AC220V/DC24V control power supply for secondary circuit
10. Prova di isolamento: Power frequency withstand test at Ui=1000V level; 12kV impulse withstand is type test only, no on-site 12kV impulse test
11. Draw-out operation: Use dedicated crank for rack-in / rack-out; prohibit racking out breaker from connected position under live condition
12. Operazione, Handling & Interlock Description

7.1 Operation Procedure

1. Charging: Manual charging handle or MCH motor auto charging; charging complete, charged indicator lights on
2. Chiusura: Local front panel close pushbutton / XF remote close; verify interlock conditions before closing
3. Apertura: Local open pushbutton / MX remote opening / automatic protection tripping; after fault trip, fault reset button must be manually reset before re-closing

7.2 Interlock (Two-incoming one bus tie scheme)

Interblocco meccanico: Steel cable mechanical interlock, physically prevents simultaneous closing of three ACBs

Interblocco elettrico: Close circuit wired in series with normally closed contacts of other breakers for double protection

Cradle position interlock: Closing circuit blocked when not in connected position, closing prohibited

Fault trip interlock: Auto-transfer closing logic blocked upon SDE contact activation

8. Manutenzione, Ispezione & Risoluzione dei problemi

8.1 Manutenzione periodica

Semi-annual: Check charging status, on/off indication, contact temperature rise, tightness of secondary wiring

Annuale: Dust cleaning, insulation inspection, trip unit test (using MicroLogic test cable)

Overhaul (ogni 5 anni): Disassemble to inspect main contacts and arc chamber, mechanical lubrication, mechanical life verification

8.2 Risoluzione dei problemi tipici

1. Mancata chiusura

Incomplete charging; undervoltage MN coil de-energized; cradle not in connected position; interlock blocked; fault trip not reset

2. Unintended tripping

Verify protection curve; guasto a terra; harmonic overload; loose wiring with overheating; voltage dip triggering MN undervoltage trip

3. Charging failure

No power supply to MCH motor; jammed charging mechanism; damaged charged-ready contact

4. No fault signal output

Wrong SDE auxiliary contact wiring, burnt contacts

9. Condizioni ambientali

Temperatura ambiente operativa: -5℃ ~ +70 ℃; declassamento richiesto sopra i 40 ℃

Temperatura di conservazione: -40℃ ~ +85 ℃

Umidità relativa: ≤95% (senza condensa)

Altitudine: ≤2000m; derating and insulation correction required above 2000m

Grado di protezione: Device IP30; IP40 with cabinet door closed

Grado di inquinamento: 3

10. Replacement Model Information

NT06H2 → MTZ1 06H2

Telaio 630A, Icu=50kA, compatible MicroLogic trip unit

Dimensioni di montaggio, primary busbar and secondary terminals fully compatible, no cabinet modification required for in-panel retrofit

Supports ECOSTRUXURE Power software commissioning, upgraded communication interface

Schneider MasterPact NT Full Series Model List (IEC Version, Discontinued ACB, Frame 630~1600A)

Regola di denominazione: NT + Frame Code + Classe di rottura

Frame Code: 06=630A; 08=800A; 10=1000A; 12=1250A; 16=1600A

Classe di rottura: N1 / H1 / H2 / L1; Costruzione: Fisso / Estrazione; Poles 3P/4P; Frame without trip unit, MicroLogic to be ordered separately

Common Base Parameters: Ui=1000 V, Uimp=12kV, Ue max AC690V, Class B selective protection

Breaking Class Definition (440V, Icu ultimate breaking capacity)

N1: 35IL

H1: 42IL

H2: 50IL (same class as NT06H2)

L1: 130IL (tipo a limitazione di corrente, application for high short-circuit capacity)

NT Full Model List

Draw-out part number: add 10 to the last digit. Example NT06H2 3P Draw-out:47203; 4P fixed part number +6 (NT06H2 4P Fixed 47119)

Derivative Isolator Models (HA version)

NTxxHA: Isolator (without trip unit, IEC60947-3)

NT06HA / NT08HA / NT10HA / NT12HA / NT16HA

Compatible Trip Unit List (Universal for full NT series)

Micrologica 2.0: Long-time overload only

MicroLogic 5.0A: A lungo + ritardo di breve durata + istantaneo (preferred for incoming / cravatta dell'autobus)

MicroLogic 6.0A: 5.0UN + protezione dai guasti a terra

MicroLogic 7.0A: 6.0UN + protezione corrente residua + harmonic measurement

Replacement Cross Reference Table (NT → MTZ1)

Selection Remarks

1. NT series fully discontinued, non consigliato per nuovi progetti; MTZ1 can be used for spare parts replacement for existing projects with compatible primary and secondary interfaces.
2. L1 current-limiting type for systems with extremely high short-circuit current, costo più elevato; H2 is preferred for normal incoming feeder and bus tie.
3. Rated current can be derated within the same frame by changing current sensor inserts, per esempio. NT06 frame available with 400A/500A/630A sensors.