Schneider 18637 Miniature circuit breaker (MCB)

Schneider Electric 18637 is a 3-pole miniature circuit breaker (MCB) from the Acti 9 NG125N range, rated at 40 A with a C tripping curve and a breaking capacity of 25 kA at 380-415 V AC per IEC 60947-2. Designed for electrical power distribution, it supports both AC and DC networks with thermomagnetic protection technology.

Technical specifications:

• Commercial reference: 18637
• Manufacturer: Schneider Electric
• EAN:
• Series / range: Acti 9 NG125
• Product type: Miniature circuit breaker (MCB)
• Short device name: NG125N
• Number of poles: 3P
• Number of protected poles: 3
• Rated current [In]: 40 A at 40°C
• Tripping curve: C
• Network type: AC / DC
• Protection technology: Thermomagnetic
• Breaking capacity [Icu]: 50 kA at 220-240 V AC; 25 kA at 380-415 V AC; 20 kA at 440 V AC; 10 kA at 500 V AC; 20 kA at up to 375 V DC (EN/IEC 60947-2)
• Service breaking capacity [Ics]: 37.5 kA (220-240 V AC); 18.75 kA (380-415 V AC); 15 kA (440 V AC); 7.5 kA (500 V AC)
• Rated voltage [Ue]: 220-240 V / 380-415 V / 440 V / 500 V AC 50/60 Hz; up to 375 V DC
• Rated insulation voltage [Ui]: 690 V AC
• Rated impulse withstand voltage [Uimp]: 8 kV
• Overcurrent protection limit: 8 x In
• Use category: Category A per IEC 60947-2
• Standard: EN/IEC 60947-2
• IP protection: IP20 (IEC 60529)
• IK protection: IK05 (EN/IEC 62262)
• Operating temperature: -30 to 70°C
• Storage temperature: -40 to 70°C
• Relative humidity: 95% at 55°C
• Mounting: 35 mm symmetrical DIN rail, click-on
• Handle position: Vertical
• Connection terminals: Tunnel terminals 1.5-50 mm² (rigid); 1-35 mm² (flexible)
• Tightening torque: 3.5 N.m
• Strip length: 20 mm
• Dimensions (WxHxD): 81 x 103 x 81 mm
• Weight: 0.72 kg
• Mechanical endurance: 20,000 cycles
• Electrical endurance: 10,000 cycles
• Busbar comb rail compatible: Yes (9 mm pitch)

Features and benefits:

• High breaking capacity of 25 kA at 380-415 V AC suitable for demanding industrial and commercial installations
• Dual AC/DC network compatibility provides flexibility across a wide range of electrical systems
• Integrated locking preparation allows the handle to be padlocked in the OFF position for safe isolation
• Contact position indicator and trip indicator enable quick visual status checks
• Click-on DIN rail mounting and comb busbar compatibility simplify panel assembly
• Wide operating temperature range (-30 to 70°C) suits both indoor and harsh-environment enclosures

Applications:

• Final and sub-distribution boards in commercial and industrial buildings
• Protection of outgoing circuits in main distribution panels
• DC circuit protection in photovoltaic and battery storage installations
• Motor and equipment protection in industrial automation panels
• High-fault-level environments requiring elevated breaking capacity

Compliant with EN/IEC 60947-2. Part of the Schneider Electric Acti 9 NG125 range.

Also known as: Schneider 18637, Schneider Electric 18637, Schneider NG125N 40A 3P MCB, Acti9 NG125N 40A circuit breaker.