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Chint NB310L-3N-B20 RCBO – 3P+N – B Curve – Type A – 20A – 30mA – 6kA
Chint NB310L-3N-B20 RCBO, a 20 A B curve 3P+N Type A residual current operated circuit breaker with overcurrent protection for three-phase electrical installations.
£60.04
Why Choose the Chint NB310L-3N-B20 RCBO?
The Chint NB310L-3N-B20 is a dependable Residual Current Circuit Breaker with Overcurrent Protection (RCBO) designed to protect three-phase electrical circuits against earth leakage, overloads and short circuits. It combines residual current protection and overcurrent protection in one compact DIN rail mounted device for reliable low-voltage electrical safety.
As part of the Chint NB310L RCBO series, this model is suitable for residential, commercial and light industrial distribution systems requiring multi-pole protection. Its 3P+N configuration provides protection and switching for three-phase circuits with neutral, supporting safe operation in distribution boards and control panels.
With a rated current of 20 A, B curve tripping characteristic, Type A residual current protection and a 30 mA residual operating current, the NB310L-3N-B20 is ideal for three-phase circuits and equipment with low inrush current. Its 6 kA breaking capacity provides dependable short circuit protection for modern electrical installations.
Key Advantages
- Compact RCBO combining residual current and overcurrent protection.
- 20 A rated current suitable for three-phase final circuits.
- B curve tripping characteristic for circuits with low inrush current.
- 3P+N configuration for three-phase electrical systems with neutral.
- Type A residual current protection detects AC and pulsating DC residual currents.
- 6 kA breaking capacity for reliable short circuit protection.
Key Features
- Chint NB310L residual current operated circuit breaker series.
- 20 A rated current.
- B curve instantaneous tripping.
- 3 pole + neutral configuration.
- Rated voltage: 230/400 V AC.
- Rated residual operating current: 30 mA.
- Type A residual current protection.
- DIN rail mounting for distribution boards and control panels.
Reliable Protection for Three-Phase Installations
RCBOs such as the Chint NB310L-3N-B20 provide combined protection against residual current faults and overcurrent conditions. This helps reduce the risk of electric shock, cable overheating and equipment damage caused by earth leakage, overloads or short circuits.
The B curve characteristic makes this model suitable for circuits with relatively low starting currents, such as lighting circuits, control circuits and resistive three-phase loads. Its Type A residual current protection detects both sinusoidal AC and pulsating DC residual currents, supporting reliable protection for modern electrical installations.
Typical Applications
- Three-phase distribution boards.
- Commercial electrical installations.
- Light industrial control panels.
- Lighting and control circuits.
- Three-phase final circuits with low inrush current.
- Equipment requiring 3P+N residual current and overcurrent protection.
Technical Specifications
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| Current | 20 A | |
|---|---|---|
| Phase | Three Phase | |
| Poles | 3-pole + N | |
| Device Type | RCBO | |
| Trip Curve | B curve | |
| Breaking Capacity | 6 kA | |
| Residual Current | 30 mA | |
| RCD Type | Type A | |
| Manufacturer | Chint | |
| Series | NB310L | |
| Model | NB310L-3N-B20 | |
| Product type | RCBO / residual current operated circuit breaker with overcurrent protection | |
| Rated current | 20 A | |
| Tripping curve | Type B | |
| Rated voltage | 230/400 V AC | |
| Frequency | 50 / 60 Hz | |
| Poles | 3P+N | |
| Residual current type | Type A | |
| Rated residual operating current | 30 mA | |
| Rated short-circuit breaking capacity | 6 kA | |
| Protection rating | IP20 | |
| Standard | IEC/EN 61009-1 | |
| Mounting type | 35 mm DIN rail | |
| Dimensions (H × W × D) | approx. 86 × 72 × 77.5 mm |
Frequently Asked Questions
What is the Chint NB310L-3N-B20 used for?
The Chint NB310L-3N-B20 is used to protect three-phase circuits with neutral against earth leakage, overloads and short circuits.
What current rating does the NB310L-3N-B20 have?
This RCBO has a rated current of 20 A, making it suitable for three-phase final circuits and control applications.
What does B curve mean on this RCBO?
A B curve RCBO is designed for circuits with low inrush current, such as lighting, control circuits and resistive electrical loads.
What residual current protection type is this model?
The NB310L-3N-B20 is a Type A RCBO, designed to detect AC and pulsating DC residual currents.
How is the Chint NB310L-3N-B20 installed?
The device is designed for installation on a standard 35 mm DIN rail inside a distribution board, consumer unit or control panel.
Trusted Circuit Protection for Modern Electrical Installations
Chint NB310L RCBOs are widely used by electricians, contractors and panel builders for dependable residual current and overcurrent protection across residential, commercial and light industrial electrical installations.
