ABB S203M-K4NA miniature circuit breaker from the System pro M compact S200M range featuring a 4 A rating, K curve characteristic, 3+NP configuration and 10 kA breaking capacity for industrial circuit protection.
£187.71
The ABB S203M-K4NA is a professional miniature circuit breaker (MCB) designed to provide reliable overload and short-circuit protection for commercial, industrial and control panel applications. As part of the trusted ABB System pro M compact S200M series, it delivers dependable current-limiting protection for modern electrical installations.
This miniature circuit breaker features a K curve tripping characteristic, making it suitable for circuits with higher inrush currents than standard B or C curve devices. It is ideal for protecting transformers, control circuits, inductive loads and machinery where nuisance tripping must be minimised while maintaining reliable fault protection.
With a rated current of 4 A, a 3+NP pole configuration and a breaking capacity of up to 10 kA at 230 / 400 V AC, the S203M-K4NA is ideal for specialised three-phase circuit protection applications requiring a switched neutral. Its compact DIN rail design enables straightforward installation within distribution boards and electrical control panels.
Miniature circuit breakers such as the ABB S203M-K4NA automatically disconnect electrical circuits during overload and short-circuit conditions, helping to protect cables, machinery and connected equipment while improving electrical safety.
The ABB S200M range combines compact dimensions with high breaking capacity and dependable performance. Its K curve characteristic makes this model particularly suitable for transformers, motors, control circuits and other equipment with elevated starting currents.
| Current | 4 A |
|---|---|
| Phase | Single Phase |
| Manufacturer | ABB |
| Series | System pro M compact S200M |
| Model | S203M-K4NA |
| Product type | Miniature circuit breaker |
| Product ID | 2CDS273103R0337 |
| EAN | 4016779659499 |
| Rated current | 4 A |
| Tripping characteristic | K curve |
| Pole configuration | 3+NP |
| Rated operational voltage | 230 / 400 V AC |
| Rated insulation voltage | 440 V |
| Frequency | 50 / 60 Hz |
| Rated breaking capacity | 10 kA |
| Current limiting class | 3 |
| Protection rating | IP20 |
| Mounting type | DIN rail mounting |
| Dimensions (H × W × D) | approx. 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 |
The ABB S203M-K4NA protects three-phase electrical circuits against overloads and short circuits, particularly where inductive loads or high inrush currents are present.
This miniature circuit breaker has a rated current of 4 A.
A K curve MCB is designed for circuits with higher inrush currents, making it suitable for motors, transformers and inductive loads.
The S203M-K4NA provides three protected phase poles together with a switched neutral pole for three-phase electrical systems.
It is designed for DIN rail installation inside electrical distribution boards, switchboards and industrial control panels.
ABB System pro M compact miniature circuit breakers are trusted by electricians, panel builders and industrial engineers for dependable circuit protection, robust construction and long-term reliability.
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LED Controls is a specialist distributor of factory automation and industrial controls, supplying OEMs, machine builders, panel builders and end users throughout the UK and worldwide. As a trusted UK distributor for many of the world’s leading automation manufacturers, we provide industrial control products, technical expertise and bespoke automation solutions backed by outstanding customer service.
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...
2025 has been a big year for LED Controls, and our blog has expanded accordingly. We've covered a wide range of topics across industrial control and factory automation this year. From core technology explainers and new product releases to panel building best practice...