• The CHINT NXB-63G series 3-Pole Miniature Circuit Breaker (MCB) is engineered to deliver superior protection for three-phase electrical circuits in demanding industrial and commercial environments.
• This MCB ensures simultaneous disconnection of all three poles, offering robust safeguarding against overload and short-circuit conditions in 415V AC systems.
• Compliant with key international and regional standards including IEC/EN 60947-2, VC8036, SANS 556-1, and SANS 60947-2, the NXB-63G 3P provides a versatile current rating from 1A to 63A, making it a reliable choice for a wide array of three-phase applications.

Features

• Three-pole (3P) configuration for comprehensive three-phase circuit protection.
• Extensive rated current range: 1A, 2A, 3A, 4A, 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A, 63A.
• Rated operational voltage: 415V AC (also suitable for 240V applications where 3-pole switching is needed).
• High short-circuit breaking capacity: 6kA (Icu) / 6kA (Ics).
• Effective overload and short-circuit protection mechanisms.
• Available with Type C and Type D trip characteristics to suit various load types.
• Compliance with standards: IEC/EN 60947-2, VC8036, SANS 556-1, SANS 60947-2.
• Rated frequency: 50/60Hz.
• Outstanding operational endurance: 20,000 mechanical cycles, 10,000 electrical cycles.
• Easy DIN rail mounting: TH35-7.5 standard.
• Clear visual On/Off status indication.
• Enclosure protection: IP20 (IP40 when mounted in a distribution box).
• Robust terminals: Designed to accommodate copper wires up to 25 mm².
• Optimized for industrial applications: Reference temperature for thermal element setting at 40°C.

Benefits

• Comprehensive Three-Phase Protection: Reliably safeguards three-phase motors, equipment, and installations from damage due to overcurrents and short circuits.
• Adaptable to Diverse Loads: The wide range of amperage ratings and trip characteristics (C, D) makes it suitable for various three-phase industrial and commercial loads.
• Guaranteed Quality & Compliance: Adherence to multiple international and regional standards ensures a high-quality, dependable, and safe product.
• Extended Service Life & Reliability: Robust construction delivers excellent mechanical and electrical durability, minimizing downtime and replacement costs.
• Simplified Installation: Standard TH35-7.5 DIN rail compatibility allows for quick and straightforward integration into distribution boards.
• Immediate Status Awareness: The clear On/Off indicator allows for rapid visual assessment of the breaker's state across all three poles.
• Secure and Durable Connections: Features robust terminals designed for lasting and safe electrical connections in three-phase systems.

In-Depth Technical Specifications

Ideal Use

• Protection of three-phase motors, machinery, and industrial equipment.
• Three-phase electrical distribution boards in commercial buildings, workshops, and industrial facilities.
• Applications requiring balanced three-phase circuit protection under IEC/EN 60947-2 standards.
• HVAC systems, pumps, and other three-phase loads.
• Control panels and automation systems utilizing three-phase power.

Tips

• Professional Installation: Ensure installation, wiring, and maintenance are performed by a qualified and licensed electrician.
• Power Isolation: Always de-energize the circuit by switching off the main power supply before installing or servicing the MCB.
• Secure Wiring: Tighten all terminal screws to the recommended torque (2.0 N·m) using an appropriate screwdriver to ensure secure, low-resistance connections and prevent overheating.
• Correct Wire Sizing: Use copper conductors with a cross-sectional area appropriate for the MCB's rated current and the connected load. Refer to the specifications for guidance.
• Load Compatibility: For direct-on-line starting of large three-phase motors with high inrush currents, consider using dedicated motor protection circuit breakers (MPCBs) or motor starters in conjunction with or instead of this MCB, depending on the application requirements.
• Balanced Loads: Strive for balanced loads across the three phases to ensure optimal performance and prevent nuisance tripping or undue stress on the system.
• Environmental Conditions: Install the MCB in an environment that complies with its operational specifications. For harsh environments, use a suitable protective enclosure.
• Derating: When multiple MCBs are installed side-by-side, consider derating factors based on ambient temperature and enclosure ventilation to ensure reliable operation.