Why Choose the ABB S203MT-K3NA Miniature Circuit Breaker?
The ABB S203MT-K3NA is a robust and compact miniature circuit breaker (MCB) designed for overload and short-circuit protection in low-voltage electrical systems. As part of the ABB S200MT miniature circuit breaker range, it is developed for demanding industrial, commercial, traction and railway applications where dependable circuit protection is essential.
This circuit breaker features a K curve tripping characteristic, making it suitable for circuits with higher inrush currents while still providing reliable protection against faults. Its current limiting design helps reduce fault energy, supporting safer operation and improved protection for cables, equipment and connected loads.
With a rated current of 3 A and a 3-pole plus neutral configuration, the ABB S203MT-K3NA is ideal for three-phase circuits requiring a switched neutral. Its modular DIN rail mounting format allows quick installation inside electrical panels, distribution boards, switchgear cabinets and machine control systems.
Key Advantages
- Compact miniature circuit breaker for circuit protection.
- 3 A rated current for low-current electrical circuits.
- 3-pole plus neutral configuration for three-phase systems with switched neutral.
- K curve tripping characteristic suitable for circuits with higher inrush currents.
- Current limiting performance helps reduce fault energy and equipment stress.
- DIN rail mounting for fast installation in electrical enclosures.
Key Features
- ABB S200MT miniature circuit breaker series.
- 3 A nominal current rating.
- 3 protected poles plus neutral.
- K type tripping curve for reliable protection of inductive loads.
- Thermal tripping mechanism for overload protection.
- Electromechanical tripping mechanism for short-circuit protection.
- Current limiting class 3 performance.
- Modular DIN rail design for control panels and distribution boards.
Miniature circuit breakers such as the ABB S203MT-K3NA protect electrical circuits by automatically disconnecting the supply when overloads or short-circuit faults occur. This helps prevent cable damage, equipment failure and unsafe fault conditions in control and distribution systems.
The K curve characteristic is designed for circuits that may experience higher starting or inrush currents, such as control transformers, motors and inductive loads. This makes the S203MT-K3NA suitable for applications where fast fault protection is required without unwanted nuisance tripping during normal operation.
Typical Applications
- Industrial control panels and automation systems.
- Railway and traction electrical installations.
- Three-phase circuits requiring switched neutral protection.
- Distribution boards and switchgear assemblies.
- Control transformers, inductive loads and auxiliary circuits.
- Machine building and OEM electrical systems.
