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ABB S203-B20NA MCB – S200 – 3P+N – B – 20A
ABB S203-B20NA three-pole plus switched neutral miniature circuit breaker with 20 A rated current, B curve tripping characteristic and 6 kA breaking capacity for industrial and commercial electrical installations.
£106.96
Why Choose the ABB S203-B20NA Miniature Circuit Breaker?
The ABB S203-B20NA is a premium three-pole plus switched neutral (3P+N) miniature circuit breaker (MCB) from the trusted ABB System pro M Compact S200 series. Designed to provide dependable overload and short circuit protection, it is ideal for commercial, industrial and OEM electrical installations requiring reliable protection of three-phase circuits with a switched neutral.
Featuring a B curve tripping characteristic and a 20 A rated current, the S203-B20NA is particularly suited to protecting lighting circuits, resistive loads, control circuits and general power distribution where low inrush currents are expected. Its advanced current limiting technology helps minimise fault energy whilst protecting connected equipment and improving overall system reliability.
Manufactured to ABB's exacting quality standards, the S203-B20NA offers outstanding mechanical durability, dependable switching performance and compatibility with ABB's comprehensive range of System pro M Compact accessories, making it an ideal choice for professional electrical installations.
Key Advantages
- Reliable 3P+N miniature circuit breaker for industrial and commercial applications.
- 20 A rated current with B curve tripping characteristic.
- 6 kA breaking capacity for dependable circuit protection.
- Protects against overloads and short circuits.
- Switched neutral provides additional installation flexibility.
- Compatible with ABB auxiliary contacts and signalling accessories.
Key Features
- ABB System pro M Compact S200 series.
- 20 A rated current.
- B characteristic trip curve.
- Three protected poles plus switched neutral (3P+N).
- 6 kA rated short circuit breaking capacity.
- DIN rail mounting.
- Thermal overload and magnetic short circuit protection.
- Failsafe bi-directional cylinder-lift terminals.
Reliable Protection for Three-Phase Electrical Systems
The ABB S203-B20NA combines thermal overload protection with rapid magnetic short circuit protection to safeguard electrical installations. Its B curve characteristic provides fast operation on low inrush current circuits, making it ideal for lighting, heating, socket outlets and general electrical distribution.
The integrated switched neutral enables simultaneous switching of the neutral conductor alongside the three live phases, making this breaker suitable for modern electrical distribution systems, industrial control panels and OEM equipment.
Typical Applications
- Industrial control panels.
- Lighting circuits.
- Commercial electrical installations.
- General power distribution.
- OEM machinery.
- Three-phase distribution systems with switched neutral.
Technical Specifications
Tick the specs you need, then view products that match.
| Phase | Three Phase | |
|---|---|---|
| Current | 20 A | |
| Poles | 3-pole + N | |
| Device Type | MCB | |
| Trip Curve | B curve | |
| Breaking Capacity | 6 kA | |
| Manufacturer | ABB | |
| Series | System pro M Compact S200 | |
| Model | S203-B20NA | |
| Product ID | 2CDS253103R0205 | |
| Product type | Miniature Circuit Breaker (MCB) | |
| Rated current | 20 A | |
| Tripping characteristic | B Curve | |
| Number of poles | 3P+N | |
| Protected poles | 3 | |
| Rated operational voltage | 400 V AC | |
| Maximum operating voltage | 440 V AC | |
| Rated frequency | 50 / 60 Hz | |
| Rated short circuit breaking capacity | 6 kA | |
| Protection rating | IP20 | |
| Mounting type | DIN rail | |
| Dimensions (H × W × D) | 88 × 70 × 69 mm | |
| Weight | Approx. 0.45 kg | |
| Standards | IEC/EN 60898-1, IEC/EN 60947-2, UL 1077 | |
| HS Code | 85362010 | |
| Country of Manufacture | Germany |
Frequently Asked Questions
What is the ABB S203-B20NA used for?
The ABB S203-B20NA protects three-phase electrical circuits with a switched neutral against overloads and short circuits in industrial and commercial applications.
What does the B curve characteristic mean?
A B curve miniature circuit breaker is designed for circuits with relatively low inrush currents, making it suitable for lighting, heating and general power distribution.
What is the rated current of this circuit breaker?
The ABB S203-B20NA has a 20 A rated current.
What does 3P+N mean?
3P+N indicates three protected phase poles with an additional switched neutral pole, allowing the neutral conductor to be switched together with the phase conductors.
How is the ABB S203-B20NA installed?
The breaker is designed for standard DIN rail mounting inside electrical distribution boards and industrial control panels.
Trusted by Electrical Professionals Worldwide
ABB System pro M Compact miniature circuit breakers are trusted worldwide by electrical contractors, panel builders and industrial engineers for dependable circuit protection, long service life and reliable performance.
