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ABB S203-K4NA MCB – S200 – 3P+N – K – 4A
ABB S203-K4NA System pro M Compact miniature circuit breaker with 3P+N configuration, 4 A rated current, K tripping characteristic and 6 kA breaking capacity for industrial circuit protection.
£103.51
Why Choose the ABB S203-K4NA Miniature Circuit Breaker?
The ABB S203-K4NA is a premium 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 for industrial, commercial and OEM electrical installations. Featuring a K tripping characteristic, this breaker is specifically engineered for circuits with elevated inrush currents, making it ideal for motors, transformers, solenoids and other inductive equipment.
Built using ABB's advanced thermal and electromagnetic tripping technology, the S203-K4NA delivers reliable circuit protection with excellent current limiting performance. Its compact DIN rail mounted design enables straightforward installation in switchboards, distribution boards and industrial control panels while remaining fully compatible with ABB's extensive range of S200 accessories.
With a 4 A rated current, 3P+N configuration and a 6 kA breaking capacity, the ABB S203-K4NA provides dependable protection for three-phase electrical systems requiring a switched neutral, ensuring reliable operation in demanding industrial environments.
Key Advantages
- 3P+N miniature circuit breaker for three-phase systems with switched neutral.
- 4 A rated current for specialised industrial protection.
- K characteristic trip curve for higher inrush current applications.
- 6 kA breaking capacity for dependable short circuit protection.
- Compact DIN rail mounting for straightforward installation.
- Compatible with ABB S200 series accessories for enhanced flexibility.
Key Features
- ABB System pro M Compact S200 series.
- Model: S203-K4NA.
- Rated current: 4 A.
- 3P+N pole configuration.
- K tripping characteristic.
- 6 kA rated short circuit capacity.
- Thermal overload and electromagnetic short circuit protection.
- Current limiting design.
- DIN rail mounting.
Reliable Protection for Industrial Power Systems
The ABB S203-K4NA automatically disconnects electrical circuits during overload and short circuit conditions, helping protect wiring, machinery and connected equipment from damage while maintaining electrical safety and operational reliability.
Its K characteristic provides a higher magnetic trip threshold than standard B and C curve devices, making it particularly suitable for motors, transformers, magnetic coils and other inductive equipment with elevated starting currents.
Typical Applications
- Industrial motor circuits.
- Machine building and OEM equipment.
- Industrial control panels.
- Transformer protection.
- Automation systems.
- Commercial and industrial power distribution.
Technical Specifications
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| Phase | Three Phase | |
|---|---|---|
| Current | 4 A | |
| Poles | 3-pole + N | |
| Device Type | MCB | |
| Trip Curve | K curve | |
| Breaking Capacity | 6 kA | |
| Manufacturer | ABB | |
| Series | System pro M Compact S200 | |
| Model | S203-K4NA | |
| Product ID | 2CDS253103R0337 | |
| Product type | Miniature Circuit Breaker (MCB) | |
| Rated current | 4 A | |
| Tripping characteristic | K | |
| Number of poles | 3P+N | |
| Rated operational voltage | 400 V AC | |
| Maximum operational voltage | 440 V AC | |
| Rated frequency | 50 / 60 Hz | |
| Rated short circuit capacity | 6 kA | |
| Energy limiting class | 3 | |
| Mounting type | DIN rail | |
| Dimensions (H × W × D) | 88 × 70 × 69 mm | |
| Weight | Approx. 0.50 kg | |
| Protection rating | IP20 (IP40 when installed in a suitable enclosure) | |
| 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-K4NA used for?
The ABB S203-K4NA protects three-phase electrical circuits with a neutral against overloads and short circuits in industrial and commercial installations.
What does the K trip characteristic mean?
The K characteristic is designed for circuits with higher inrush currents, making it suitable for motors, transformers and other inductive loads.
What is the rated current of this breaker?
This miniature circuit breaker has a 4 A rated current.
How is the S203-K4NA installed?
The breaker mounts directly onto a standard 35 mm DIN rail inside switchboards, distribution boards and industrial control panels.
Can ABB accessories be fitted?
Yes. The ABB S200 range supports auxiliary contacts, shunt trips, undervoltage releases, motor operators and other compatible accessories.
Trusted by Electrical Professionals Worldwide
ABB System pro M Compact miniature circuit breakers are trusted by electrical contractors, panel builders and industrial engineers worldwide for dependable circuit protection, excellent build quality and long service life.
