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50A 1 Pole B Curve 6KA MCB (NB1‑63B1P50)

Chint 50A 1 Pole B Curve MCB (NB1‑63B1P50) offers dependable overload and short‑circuit protection with a 6 kA breaking capacity. DIN-rail mountable, compact and ideal for residential and commercial electrical circuits.

Trusted circuit protection with reliable overload and short‑circuit trip performance. 50 A rated current and 6 kA breaking capacity suitable for most UK electrical installations. B-curve tripping characteristic optimised for everyday loads like lighting and power circuits. DIN-rail mountable and compact design fits standard consumer units with ease. Durable, high-quality construction with IP20 protection for long service life.
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SKU: NB1-63B1P50
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Product Details

The 50A 1 Pole B Curve 6KA MCB (NB1‑63B1P50) from Chint is a reliable miniature circuit breaker designed to protect electrical circuits from overload and short‑circuit faults in domestic, commercial and light industrial installations. Compact and robust, this single‑pole breaker fits neatly into distribution boards and control panels, giving you trusted protection where it matters most.

Made with high-quality materials and a durable thermoplastic body, this MCB offers dependable performance at a maximum rated current of 50 amps and a breaking capacity of 6 kiloamps, meeting standard safety requirements. The B-curve characteristic means the breaker trips quickly on lower levels of overcurrent, making it ideal for typical residential circuits such as lighting, sockets and general power feeds where sensitive protection is needed.

Installation is simple with a DIN-rail mountable design and standard 18 mm modular width that fits most UK consumer units. The sturdy construction includes an IP20 protection rating, helping guard internal components while allowing smooth operation in everyday environments. This MCB also supports a wide temperature range and is compliant with international safety standards, ensuring long-lasting service and peace of mind for installers and end users alike.

Whether you are wiring a new property, upgrading an existing panel or replacing a worn-out breaker, the Chint NB1‑63B1P50 delivers dependable circuit protection with consistent performance and proven quality.

Product Specifications

Electrical Specifications

  • Model: NB1-63B1P50
  • Rated Current (In): 50A
  • Number of Poles: 1P
  • Tripping Curve: B Curve (3-5 In)
  • Rated Voltage (Ue): 230/400V AC
  • Rated Frequency: 50/60Hz
  • Rated Short-circuit Capacity (Icn): 6,000A (6kA)
  • Rated Insulation Voltage (Ui): 500V
  • Rated Impulse Withstand Voltage (Uimp): 4,000V (4kV)
  • Energy Limiting Class: 3
  • Power Loss per Pole: 5W
  • Release Type: Thermo-magnetic

Mechanical & Installation Data

  • Mounting: 35mm DIN Rail (EN 60715) via fast clip device
  • Terminal Connection Type: Cable / U-type busbar / Pin-type busbar
  • Terminal Size (Cable): Up to 25mm² (18-4 AWG)
  • Terminal Size (Busbar): Up to 10mm² (18-8 AWG)
  • Tightening Torque: 2.5 N·m (22 In-lbs)
  • Connection Direction: From top and bottom
  • Electrical Life: 4,000 operations
  • Mechanical Life: 20,000 operations
  • Protection Degree: IP20
  • Contact Position Indicator: Yes (Color-coded visual indication)

Environmental Specifications

  • Ambient Operating Temperature: -5°C to +40°C (Daily average ≤ 35°C)
  • Storage Temperature: -25°C to +70°C
  • Reference Temperature for Tripping: 30°C
  • Pollution Degree: 2

Dimensions

  • Width: 18mm (1 module)
  • Height: 86mm
  • Overall Depth: 78mm

Key Features

  • Reliable Protection: Engineered to protect circuits against short-circuit and overload currents, specifically for TN and IT earthing systems.
  • Integrated Safety: Features a trip-free mechanism, ensuring the circuit breaker operation cannot be defeated by holding the handle in the "ON" position.
  • Efficient Cooling: Includes a built-in heat dissipation gap to provide better cooling during sustained operation.
  • Visual Status Monitoring: Equipped with a color-coded contact position indicator that provides clear visual confirmation of the device status and insulation function.
  • Flexible Installation: Features an extendable DIN-rail holder for easy installation and terminals that accept both wire and various busbar types for reduced installation costs.

Standards & Compliance

  • Primary Standard: IEC/EN 60898-1
  • Certification: CE Marked, ASTA Licensed, VDE, KEMA, SEMKO, RCC, UL Verified

Shipping & Collection

Tracked Delivery (Currently 1-3 business days):

  • Free over £250.
  • £5.99 for orders under £250.
  • £5.99 for orders under £50.

Next Business Day Delivery:

  • £15 Flat Rate.

Collection:

  • Free to collect from our warehouse.

Pre-Order:

  • 5-10 Business Days delivery unless otherwise stated.

Shipping Policy

Datasheets
50A 1 Pole B Curve 6KA MCB (NB1‑63B1P50) - Data Sheet
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