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ABB S203M-B50NA MCB – S200M – 3P+N – B – 50A
ABB S203M-B50NA miniature circuit breaker from the System pro M compact S200M series, rated at 50 A with B curve tripping characteristic and 3P+N configuration for low-voltage circuit protection.
£96.87
Why Choose the ABB S203M-B50NA Miniature Circuit Breaker?
The ABB S203M-B50NA is a high-performance miniature circuit breaker (MCB) designed to protect electrical circuits against overloads and short circuits. As part of the trusted ABB System pro M compact S200M series, this device provides dependable circuit protection for residential, commercial and industrial low-voltage installations.
This 50 amp B-curve circuit breaker combines delayed thermal overload protection with electromechanical short-circuit tripping, helping to safeguard cables, equipment and distribution circuits. Its compact DIN rail design and current-limiting performance support safe, efficient installation inside modern distribution boards and control panels.
With a rated current of 50 A and a 3P+N configuration, the S203M-B50NA is suitable for three-phase circuits requiring neutral switching. The B tripping characteristic is ideal for circuits with low inrush currents, including lighting, control circuits and general electrical distribution.
Key Advantages
- Reliable miniature circuit breaker for overload and short-circuit protection.
- 50 A rated current for commercial and industrial circuits.
- B curve tripping characteristic for circuits with low inrush current.
- 3P+N pole configuration for three-phase systems with neutral.
- Compact DIN rail mounting design for panels and distribution boards.
- Complies with key international standards including IEC/EN 60898-1 and IEC/EN 60947-2.
Key Features
- ABB System pro M compact S200M series.
- 50 A rated current.
- B tripping characteristic.
- 3P+N configuration.
- Thermal tripping mechanism for overload protection.
- Electromechanical tripping mechanism for short-circuit protection.
- 10 kA breaking capacity at 230/400 V AC.
- DIN rail mounting for straightforward installation.
Reliable Circuit Protection for Low-Voltage Installations
Miniature circuit breakers such as the ABB S203M-B50NA automatically disconnect a circuit when overload or short-circuit conditions occur. This helps protect wiring, connected equipment and electrical installations from damage caused by excessive current.
The B curve characteristic provides fast protection for circuits with low starting currents. The S200M series is widely used by panel builders, contractors and industrial engineers who need reliable circuit protection in compact DIN rail assemblies.
Typical Applications
- Three-phase electrical distribution boards.
- Commercial and industrial control panels.
- Lighting and general power distribution circuits.
- Control circuits and low inrush current loads.
- Building services and facility electrical systems.
- OEM equipment and panel building applications.
Technical Specifications
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| Phase | Three Phase | |
|---|---|---|
| Current | 50 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-B50NA | |
| Product type | Miniature circuit breaker | |
| Manufacturer part number | 2CDS273103R0505 | |
| EAN | 4016779543958 | |
| Rated current | 50 A | |
| Tripping characteristic | B curve | |
| Number of poles | 3P+N | |
| Rated operational voltage | 400 V AC | |
| Rated insulation voltage | 440 V | |
| Rated breaking capacity | 10 kA at 230/400 V AC | |
| Standards | IEC/EN 60898-1, IEC/EN 60947-2 | |
| Degree of protection | IP20 | |
| Mounting type | DIN rail | |
| Dimensions (H × W × D) | approx. 88 × 70 × 69 mm | |
| Weight | approx. 0.5 kg | |
| HS Code | 85362010 | |
| Country of Manufacture | Germany |
Frequently Asked Questions
What is the ABB S203M-B50NA used for?
The ABB S203M-B50NA is used to protect low-voltage electrical circuits against overloads and short circuits in distribution boards, control panels and industrial installations.
What current rating does this MCB have?
This miniature circuit breaker has a rated current of 50 A.
What does the B curve mean?
The B curve tripping characteristic is suitable for circuits with low inrush currents, such as lighting, control circuits and general distribution circuits.
How many poles does the S203M-B50NA have?
The S203M-B50NA has a 3P+N configuration, making it suitable for three-phase circuits with neutral switching.
Where is this circuit breaker typically installed?
It is typically installed on DIN rail inside electrical distribution boards, control panels and industrial enclosures.
Trusted by Electrical Professionals Worldwide
ABB System pro M compact miniature circuit breakers are widely used by panel builders, electrical contractors and industrial engineers for reliable circuit protection in modern low-voltage installations.
