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Chint NB1-63D4P40 MCB – 4P – D Curve – 40A – 6kA
Chint NB1-63D4P40 40A four pole D curve miniature circuit breaker with 6kA breaking capacity for overload, short circuit and isolation protection in commercial and industrial electrical installations.
£24.79
Why Choose the Chint NB1-63D4P40 Miniature Circuit Breaker?
The Chint NB1-63D4P40 is a robust four-pole miniature circuit breaker (MCB) designed to provide reliable overload, short circuit and isolation protection for low-voltage electrical installations. As part of the dependable Chint NB1-63 series, it is suitable for commercial, industrial and OEM applications requiring consistent electrical protection.
Featuring a D curve tripping characteristic, this MCB is specifically designed for circuits supplying equipment with high inrush currents, including motors, transformers, compressors and other inductive loads. Its compact DIN rail mounted design enables fast installation within electrical distribution boards and industrial control panels.
With a 40 A rated current, 6 kA breaking capacity and a four-pole configuration, the NB1-63D4P40 provides dependable protection while allowing simultaneous isolation of all live conductors in three-phase electrical systems.
Key Advantages
- Reliable overload and short circuit protection.
- 40 A rated current for higher capacity electrical circuits.
- D curve tripping characteristic for high inrush current applications.
- 6 kA breaking capacity for dependable fault interruption.
- Four-pole design for complete circuit isolation.
- Compact DIN rail mounting simplifies installation.
- Suitable for commercial, industrial and OEM control systems.
Key Features
- Chint NB1-63 miniature circuit breaker series.
- 40 A rated current.
- D curve tripping characteristic.
- 4 pole (4P) configuration.
- 6 kA rated breaking capacity.
- Provides overload, short circuit and isolation protection.
- Suitable for AC 50/60 Hz electrical systems.
- Compact modular DIN rail mounted construction.
Reliable Protection for High Inrush Current Circuits
Miniature circuit breakers automatically disconnect electrical circuits when overload or short circuit faults occur, helping to protect wiring, connected equipment and personnel. The NB1-63D4P40 combines thermal and magnetic tripping mechanisms to provide fast and reliable fault protection.
Its D curve characteristic is intended for circuits with significant starting currents, making it ideal for motors, transformers and other inductive equipment while reducing nuisance tripping during normal operation.
Typical Applications
- Industrial distribution boards.
- Motor and transformer circuits.
- Commercial electrical installations.
- Machine building and OEM equipment.
- Three-phase switchboards.
- Industrial control panels.
Technical Specifications
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| Current | 40 A | |
|---|---|---|
| Phase | Three Phase | |
| Poles | 4-pole | |
| Device Type | MCB | |
| Trip Curve | D curve | |
| Breaking Capacity | 6 kA | |
| Manufacturer | Chint | |
| Series | NB1-63 | |
| Model | NB1-63D4P40 | |
| Product type | Miniature Circuit Breaker (MCB) | |
| Rated current | 40 A | |
| Number of poles | 4 Pole | |
| Tripping characteristic | D Curve | |
| Rated breaking capacity | 6 kA | |
| Rated short-circuit service capacity | 6 kA | |
| Rated voltage | 400 V AC | |
| Rated frequency | 50 / 60 Hz | |
| Rated insulation voltage | 500 V | |
| Rated impulse withstand voltage | 4 kV | |
| Standard | IEC/EN 60898-1 | |
| Mounting type | 35 mm DIN rail | |
| Protection rating | IP20 | |
| Mechanical life | Up to 20,000 operations | |
| Electrical life | Up to 4,000 operations | |
| Width | 18 mm per pole (72 mm total) |
Frequently Asked Questions
What is the Chint NB1-63D4P40 used for?
It protects four-pole electrical circuits against overloads and short circuits while providing safe circuit isolation during maintenance.
What current rating does this miniature circuit breaker have?
The NB1-63D4P40 has a rated current of 40 A.
What does the D curve tripping characteristic mean?
D curve MCBs are designed for circuits supplying equipment with high inrush currents, including motors, transformers and compressors.
What is the breaking capacity of this circuit breaker?
The NB1-63D4P40 provides a rated short circuit breaking capacity of 6 kA.
Where is this MCB typically installed?
It is designed for installation on a standard 35 mm DIN rail inside distribution boards, switchboards and industrial control panels.
Trusted by Electrical Professionals Worldwide
Chint NB1 miniature circuit breakers are trusted by electricians, panel builders and industrial engineers for delivering dependable circuit protection, reliable fault interruption and long-term performance across demanding low-voltage electrical installations.
