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ABB S203M-B20NA MCB – S200M – 3P+N – B – 20A
ABB S203M-B20NA miniature circuit breaker from the System pro M compact S200M range featuring a 20 A rating, B curve tripping characteristic, 3+NP configuration and 10 kA breaking capacity for reliable circuit protection.
£91.47
Why Choose the ABB S203M-B20NA Miniature Circuit Breaker?
The ABB S203M-B20NA is a high quality miniature circuit breaker (MCB) designed to provide reliable overload and short-circuit protection in residential, commercial and industrial electrical installations. As part of the professional ABB System pro M compact S200M series, it delivers dependable circuit protection for distribution boards, switchboards and control panels.
This miniature circuit breaker features a B curve tripping characteristic, making it suitable for standard electrical circuits with low inrush currents. It is commonly used for lighting circuits, socket outlet circuits and general power distribution where fast fault disconnection and reliable circuit protection are required.
With a rated current of 20 A, a 3+NP pole configuration and a breaking capacity of up to 10 kA, the S203M-B20NA is ideal for three-phase electrical systems requiring a switched neutral. Its compact DIN rail mounting design enables quick installation in modern modular electrical enclosures.
Key Advantages
- Reliable ABB miniature circuit breaker for electrical circuit protection.
- 20 A rated current for general-purpose three-phase circuits.
- B curve tripping characteristic for low inrush current applications.
- 3+NP configuration for three-phase systems with neutral switching.
- Current-limiting design helps protect cables and connected equipment.
- DIN rail mounting for fast installation in distribution boards and panels.
Key Features
- ABB System pro M compact S200M series.
- 20 A rated current.
- B curve tripping characteristic.
- 3+NP pole configuration.
- 10 kA rated breaking capacity at 230 / 400 V AC.
- Thermal tripping mechanism for overload protection.
- Electromechanical tripping mechanism for short-circuit protection.
- Compact modular design for DIN rail mounting.
Reliable Protection for Three-Phase Electrical Circuits
Miniature circuit breakers such as the ABB S203M-B20NA automatically disconnect electrical circuits during overload or short-circuit conditions. This helps protect cables, equipment and connected loads while supporting safe and compliant electrical installation design.
The ABB S200M range is engineered for professional installations requiring compact dimensions, dependable performance and high breaking capacity. Its modular format makes it suitable for use in electrical distribution boards, industrial panels and building services applications.
Typical Applications
- Commercial distribution boards.
- Residential and building services installations.
- Lighting and socket outlet circuits.
- Three-phase power distribution systems.
- Industrial control panels.
- OEM electrical panels and switchboards.
Technical Specifications
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| Phase | Three Phase | |
|---|---|---|
| Current | 20 A | |
| Poles | 3-pole + N | |
| Device Type | MCB | |
| Trip Curve | B curve | |
| Breaking Capacity | 10 kA | |
| Manufacturer | ABB | |
| Series | System pro M compact S200M | |
| Model | S203M-B20NA | |
| Product type | Miniature circuit breaker | |
| Product ID | 2CDS273103R0205 | |
| EAN | 4016779549783 | |
| Rated current | 20 A | |
| Tripping characteristic | B curve | |
| Pole configuration | 3+NP | |
| Rated operational voltage | 230 / 400 V AC | |
| Frequency | 50 / 60 Hz | |
| Rated breaking capacity | 10 kA | |
| Protection rating | IP20 | |
| Mounting type | DIN rail mounting | |
| Dimensions (H × W × D) | 88 × 70 × 69 mm | |
| Weight | approx. 0.50 kg | |
| Standards | IEC/EN 60898-1, IEC/EN 60947-2 | |
| HS Code | 85362010 | |
| Country of Manufacture | Germany |
Frequently Asked Questions
What is the ABB S203M-B20NA used for?
The ABB S203M-B20NA is used to protect three-phase electrical circuits against overloads and short circuits in distribution boards, control panels and building installations.
What current rating does this MCB have?
This miniature circuit breaker has a rated current of 20 A.
What does the B curve characteristic mean?
A B curve MCB is designed for circuits with low inrush currents, such as lighting, socket outlet and general distribution circuits.
What does the 3+NP configuration mean?
The S203M-B20NA provides three protected phase poles together with a neutral pole, making it suitable for three-phase systems requiring neutral switching.
Where is this miniature circuit breaker installed?
It is designed for DIN rail installation inside distribution boards, switchboards and electrical control panels.
Trusted by Electrical Professionals Worldwide
ABB System pro M compact miniature circuit breakers are trusted by electricians, panel builders and industrial engineers for reliable protection, compact installation and long-term performance in modern electrical systems.
