Chint NBH8-40-B40 MCB - 1P+N - B Curve - 40A - 4.5kA

Chint NBH8-40-B40 MCB – 1P+N – B Curve – 40A – 4.5kA

Chint NBH8-40-B40 40A B curve 1P+N miniature circuit breaker designed for overload and short-circuit protection in low voltage electrical distribution systems.

SKU: NBH8-40-B40Alt SKU: NBH840B40MPN: NBH8-40-B40
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List Price £16.66 ex VAT
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Why Choose the Chint NBH8-40-B40 Miniature Circuit Breaker?

The Chint NBH8-40-B40 is a compact and dependable 40 A miniature circuit breaker (MCB) designed to provide overload and short-circuit protection for low voltage electrical circuits. As part of the Chint NBH8-40 series, it delivers reliable protection and safe circuit isolation for residential, commercial and light industrial electrical installations.

Featuring a B curve tripping characteristic, this MCB is ideal for circuits with low inrush current, including lighting circuits, general socket outlets and resistive loads. Its compact 1P+N configuration combines live conductor protection with neutral switching, helping reduce installation space within modern distribution boards.

With a rated current of 40 A and a 230/240 V AC operating voltage, the NBH8-40-B40 offers dependable protection while supporting straightforward DIN rail installation in consumer units, switchboards and control panels.

Key Advantages

  • Compact 40 A miniature circuit breaker for final circuit protection.
  • B curve tripping characteristic for low inrush current applications.
  • 1P+N configuration combines live protection with neutral switching.
  • Protects against overload and short-circuit faults.
  • Suitable for 230/240 V AC low voltage distribution systems.
  • DIN rail mounting for quick installation in electrical distribution boards.

Key Features

  • Chint NBH8-40 miniature circuit breaker series.
  • 40 A rated current.
  • B curve trip characteristic.
  • 1P+N pole configuration.
  • 230/240 V AC rated operational voltage.
  • Provides overload and short-circuit protection.
  • Suitable for circuit isolation and switching.
  • Compact modular DIN rail design.

Reliable Protection for Low Voltage Circuits

Miniature circuit breakers such as the Chint NBH8-40-B40 automatically disconnect the electrical supply when overload or short-circuit conditions occur. This helps protect wiring, connected equipment and electrical installations while improving overall safety and system reliability.

The B curve trip characteristic is intended for circuits with relatively low inrush current, making the NBH8-40-B40 suitable for lighting, socket outlets, distribution circuits and other general electrical applications where dependable protection is essential.

Typical Applications

  • Residential consumer units and distribution boards.
  • Commercial electrical installations.
  • Lighting and socket outlet circuits.
  • General low voltage power distribution.
  • Electrical control panels.
  • Circuit isolation and protection applications.

Technical Specifications

Phase Single Phase
Current 40 A
Manufacturer Chint
Series NBH8-40
Model NBH8-40-B40
Product type Miniature circuit breaker
Rated current 40 A
Trip curve B curve
Number of poles 1P+N
Rated operational voltage 230/240 V AC
Rated frequency 50 / 60 Hz
Rated insulation voltage 500 V
Rated impulse withstand voltage 4 kV
Breaking capacity 4.5 kA or 6 kA depending on version
Standard IEC/EN 60898-1
Energy limiting class Class 3
Protection degree IP20
Mechanical life 20,000 operations
Electrical life 10,000 operations
Mounting type 35 mm DIN rail
Terminal connection Cable or pin-type busbar
Operating temperature -5°C to +40°C
Dimensions (W × H × D) approx. 44 × 86 × 60.7 mm
Weight approx. 120 g
Poles 1-pole + N
Device Type MCB
Trip Curve B curve
Breaking Capacity 4.5 kA

Frequently Asked Questions

What is the Chint NBH8-40-B40 used for?

The Chint NBH8-40-B40 protects electrical circuits against overloads and short circuits in residential, commercial and light industrial installations.

What current rating does this circuit breaker have?

This miniature circuit breaker has a rated current of 40 A.

What does the B curve trip characteristic mean?

A B curve breaker is designed for circuits with relatively low inrush current, making it suitable for lighting, resistive loads and general distribution circuits.

What pole configuration does this MCB use?

The NBH8-40-B40 features a 1P+N configuration, providing live conductor protection together with neutral switching.

Where is this miniature circuit breaker typically installed?

It is designed for installation on a 35 mm DIN rail inside consumer units, distribution boards and electrical control panels.

Trusted by Electrical Professionals Worldwide

Chint NBH8 miniature circuit breakers are trusted by electrical contractors, panel builders and maintenance engineers for reliable protection, long service life and dependable performance across a wide range of low voltage electrical installations.

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