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Chint NB1L-B40 RCBO – 1P+N – B Curve – Type AC – 40A – 30mA – 6kA
Chint NB1L-B40 RCBO featuring a 40 A current rating, B curve characteristic, 30 mA residual current sensitivity, 1P+N configuration and 6 kA breaking capacity.
£29.34
Why Choose the Chint NB1L-B40 RCBO?
The Chint NB1L-B40 is a compact and reliable residual current operated circuit breaker with over-current protection (RCBO) designed for residential, commercial and light industrial electrical installations. As part of the Chint NB1L series, it combines earth leakage protection, overload protection and short-circuit protection within a single modular device.
Featuring a 1P+N configuration, this RCBO is suitable for single-phase circuits requiring comprehensive electrical protection. Its B curve tripping characteristic is designed for circuits with low inrush currents, while the 30 mA residual current sensitivity provides additional protection against electric shock and earth leakage faults.
With a rated current of 40 A, a rated voltage of 230 / 240 V AC and a short-circuit breaking capacity of 6 kA, the NB1L-B40 is ideal for higher load radial circuits, distribution circuits and selected final circuit applications. Its compact DIN rail mounting design enables straightforward installation in consumer units and distribution boards.
Key Advantages
- Compact RCBO combining RCD and MCB protection.
- 40 A rated current for higher load circuits.
- 30 mA residual current sensitivity for additional personal protection.
- B curve characteristic for circuits with low inrush currents.
- 6 kA short-circuit breaking capacity for dependable fault protection.
- Quick DIN rail installation in consumer units and distribution boards.
Key Features
- Chint NB1L series RCBO.
- 40 A rated current.
- 30 mA residual operating current.
- 1P+N configuration.
- B curve thermo-magnetic trip characteristic.
- Type AC residual current protection.
- 6 kA rated short-circuit capacity.
- DIN rail mounting for modular electrical installations.
Combined Circuit and Earth Leakage Protection
The Chint NB1L-B40 combines the functions of a miniature circuit breaker and residual current device within one compact unit. It automatically disconnects the circuit during overloads, short circuits or earth leakage faults, helping protect both people and electrical installations.
Using an RCBO on individual circuits helps reduce unnecessary disruption, as faults are isolated to the affected circuit rather than disconnecting multiple circuits protected by a shared RCD.
Typical Applications
- Consumer units and distribution boards.
- Higher load radial circuits.
- Residential electrical installations.
- Commercial buildings.
- Selected distribution circuits.
- Electrical panels requiring combined over-current and residual current protection.
Technical Specifications
Tick the specs you need, then view products that match.
| Poles | 1-pole + N | |
|---|---|---|
| Current | 40 A | |
| Phase | Single Phase | |
| Device Type | RCBO | |
| Trip Curve | B curve | |
| Breaking Capacity | 6 kA | |
| Residual Current | 30 mA | |
| RCD Type | Type AC | |
| Manufacturer | Chint | |
| Series | NB1L | |
| Model | NB1L-B40 | |
| Product type | Residual current operated circuit breaker with over-current protection (RCBO) | |
| Configuration | 1P+N | |
| Rated current | 40 A | |
| Residual operating current | 30 mA | |
| Residual current type | Type AC | |
| Tripping curve | B curve | |
| Rated voltage | 230 / 240 V AC | |
| Rated frequency | 50 / 60 Hz | |
| Rated short-circuit capacity | 6 kA | |
| Rated insulation voltage | 500 V | |
| Rated impulse withstand voltage | 4 kV | |
| Mounting type | 35 mm DIN rail | |
| Protection rating | IP20 | |
| Operating temperature | approx. -25 to +40°C | |
| Standards | IEC / EN 61009-1 |
Frequently Asked Questions
What is the Chint NB1L-B40 used for?
The Chint NB1L-B40 protects single-phase circuits against overloads, short circuits and earth leakage faults.
What current rating does this RCBO have?
The NB1L-B40 has a rated current of 40 A.
What does the B curve characteristic mean?
A B curve RCBO trips between 3 and 5 times its rated current, making it suitable for circuits with low inrush currents.
What residual current sensitivity does it provide?
This RCBO provides a 30 mA residual operating current sensitivity for additional personal protection.
Is the NB1L-B40 suitable for DIN rail mounting?
Yes. The device is designed for quick installation onto standard 35 mm DIN rails within consumer units and distribution boards.
Trusted by Electrical Installers Worldwide
Chint NB1L RCBOs are widely used by electricians, panel builders and maintenance engineers to provide dependable combined over-current and residual current protection across residential and commercial installations.
