Schneider Acti9 C120N 125A Miniature Circuit Breaker

The C120N belongs to the Acti9 series high-current disjuntor miniatura (MCB). It is an upgraded high-current variant of the standard C65N, with a maximum rated current of 125A and isolation function. Widely used for power distribution in industrial and building terminals, as well as outgoing circuits in power cabinets.

1. Definição de modelo

C120: Série de produtos, high-current MCB (63~125A)

N: Classe de capacidade de ruptura, Icn=10kA @ 400V AC

125UM: Rated working current In=125A (reference temperature: 30℃)

Full model requires additional [número do pólo + curva de disparo]

Curva C: Instantaneous tripping at 5~10In, para distribuição geral de energia, lighting and resistive loads (Número da peça. A9N18359 / A9N18363 / A9N18369)

Curva D: Instantaneous tripping at 10~14In, for loads with inrush current such as motors and transformers (Número da peça. A9N18389)

2. Especificações elétricas principais

3. Especificações de fiação

Solid copper cable: Máx.. 50mm²

Flexible copper cable: Máx.. 35mm²

Optional aluminum terminal: For 16~50mm² aluminum cables

4. Cenários de aplicação
5. High-current outgoing circuits in factory buildings, computer rooms and building distribution cabinets
6. Main power incoming, fan and water pump circuits (D-curve recommended)
7. Alternative to small-frame moulded case circuit breakers to save cabinet space

Acessórios opcionais: Vigi C120 residual current module, contato auxiliar, fault alarm contact, liberação de derivação

5. Diretrizes de seleção & Produtos Alternativos

Notas de seleção

1. Derating is required when ambient temperature exceeds 30℃;
2. D-curve is preferred for motor loads; C-curve for general distribution;
3. C120N with 10kA breaking capacity; select C120H (15o) / C120L (25o) for circuits with higher short-circuit current.

Alternativas Domésticas

Chint: NM1-125 compact MCCB / NB1-125 MCB

Delicioso: CDB2 125 series miniature circuit breaker

6. Solução de problemas comuns
7. Viagens imediatamente após o fechamento: Short circuit on downstream side, check cable insulation and load earth fault;
8. Trips after period of loaded operation: Sobrecarga, actual load exceeds 125A, or high ambient temperature causes derating;
9. Não é possível fechar, handle stuck: Damaged internal mechanism, or Vigi residual current module triggered;
10. Green indicator does not appear: Main contacts are not fully disconnected. Maintenance on downstream circuits is prohibited.
11. Referência do Código HS

85362000 Low-voltage circuit breaker (for customs declaration reference only, subject to customs verification)

Schneider Acti9 C120N 125A Product Manual (Compiled from Original Datasheet)

Série: Acti9 C120N High-current Miniature Circuit Breaker (MCB)

Corrente nominal: 125UM (reference at 30℃)

Capacidade de ruptura: Icn=10kA @400V AC

Reference part numbers:

2P C-curve: A9N18363

3P C-curve: A9N18369

4P C-curve: A9N18376

3P D-curve: A9N18389

The C120N is part of Schneider Acti9 high-current MCB family covering 63~125A. It features isolation function. The green contact indicator provides direct visual confirmation that main contacts are open, meeting maintenance safety requirements. It provides thermal-magnetic protection against overload and short-circuit for high-current power distribution in industrial and building distribution cabinets. Compatible with add-on accessories including Vigi C120 residual current module, contatos auxiliares, alarm contacts and shunt releases.

Padrões: GB10963.1, IEC/EN60898-1, IEC/EN60947-2; CCC, Certificado CE

2. Especificações Elétricas

3. Mecânico & Especificações de fiação
4. Montagem: 35trilho DIN padrão mm, tipo snap-in, mountable in any orientation
5. Classe de proteção: IP20 (front terminals)
6. Capacidade de fiação

Solid copper cable: Max.50mm²

Flexible copper cable (with cable lug): Max.35mm²

Optional aluminum terminals: For 16~50mm² aluminum cables

4. Torque de aperto: 3.5 N·m
5. Dimensões gerais (18mm por pólo)

2P: 36mm largura; 3P: 54mm largura; 4P:72mm largura

6. Ambiente operacional

Temperatura ambiente: -25℃ ~ +70 ℃; derating required above 30℃

Temperatura de armazenamento: -40℃ ~ +85 ℃

Altitude: No derating ≤2000m; desclassificação necessária acima de 2.000 m

Umidade relativa: 5~95%, sem condensação

4. Características de disparo
5. Thermal overload trip (tempo inverso)

1.13Em: No tripping within 1h (estado frio)

1.45Em: Tripping within 1h

2. Magnetic instantaneous trip

Curva C:5~ 10 pol., distribuição de energia, iluminação, cargas resistivas

Curva D:10~14In, motores, transformadores, capacitor loads with inrush current

5. Acessórios opcionais
6. Vigi C120: Add-on residual current protection module, forms RCD+MCB combination
7. OF Auxiliary contact: Circuit ON/OFF status signal
8. SD Fault alarm contact: Tripping signal for short-circuit / sobrecarga
9. MX Shunt release: Remote electrical trip
10. MN Undervoltage release: Proteção contra perda de tensão
11. Barramento: Comb-type busbar for multi-pole parallel incoming connection
12. Instalação & Notas de Operação
13. Desclassificação: Derate rated current when ambient temperature >30℃. Derating also required for multiple devices installed side by side inside enclosed cabinets.
14. Isolation verification: When handle is set to OFF position, the green indicator visible confirms main contacts are fully open before downstream maintenance. Handle position alone cannot be used as isolation confirmation.
15. Fiação: Top-in or bottom-in wiring is acceptable. Cable lugs are recommended. Tightening torque 3.5N·m to prevent overheating.
16. Model differentiation

C120N:10o; C120H:15o; C120L:25o. Select H/L version for circuits with high short-circuit current.

7. Solução de problemas
8. Viagens imediatamente após o fechamento: Short circuit or earth fault on downstream side. Test breaker separately after disconnecting load to verify breaker integrity.
9. Trips after loaded operation: Actual load exceeds rated current, or high ambient temperature causes derating.
10. Não é possível fechar, handle stuck: Damaged mechanism or locked residual current module.
11. Overheating when closed: Insufficient terminal torque, undersized cable, oxidized terminals.
12. Model Selection Table (C120N 125A)

Schneider Acti9 C120N 125A Overall & Dimensões de montagem (Folha de dados original)

Referência: Height H=81mm, Depth D=73mm, height and depth are consistent for all pole types; width varies with pole count

Trilho de montagem: 35mm standard symmetrical DIN rail, snap-in installation

Common model: 3P C120N 125A (A9N18369): 81(C) × 81(H) ×73(D) milímetros

Related Mounting Dimensions

1. Comprimento de decapagem do cabo: 15 milímetros
2. Torque de aperto dos terminais: 3.5 N·m
3. Max terminal wiring: Solid wire 50mm² / Flexible wire 35mm²
4. Cabinet clearance: ≥20mm wiring space reserved at top and bottom terminals; keep heat dissipation gap for side-by-side installation at high temperature (desclassificação)

Notas Suplementares

Depth 73mm: Total depth from DIN rail backplate to front handle of breaker body; cabinet door cutout needs clearance allowance

Height 81mm: Overall vertical height of device body, excluding cable bending allowance

If Vigi C120 residual current module is fitted, overall depth increases, refer to separate accessory datasheet for dimension