Why Choose the ABB S203MT-K8NA Miniature Circuit Breaker?
The ABB S203MT-K8NA is a compact and high-performance miniature circuit breaker (MCB) designed to provide reliable overload and short-circuit protection in low-voltage electrical installations. As part of the ABB S200MT miniature circuit breaker range, it is engineered for demanding industrial, traction and railway applications where dependable circuit protection and compact installation are essential.
This circuit breaker features a K curve tripping characteristic, making it suitable for circuits with higher inrush currents such as transformers, motors and inductive loads. Its current limiting performance helps reduce fault energy, supporting safer operation and improved protection for cables, control equipment and connected devices.
With a rated current of 8 A and a 3-pole plus neutral configuration, the ABB S203MT-K8NA is ideal for three-phase circuits where the neutral conductor needs to switch together with the protected phases. Its modular DIN rail mounting design allows straightforward installation inside control panels, distribution boards, switchgear cabinets and machinery enclosures.
Key Advantages
- Compact miniature circuit breaker for circuit protection.
- 8 A rated current for low-voltage electrical circuits.
- 3-pole plus neutral configuration for three-phase systems with switched neutral.
- K curve tripping characteristic for circuits with higher inrush currents.
- 10 kA breaking capacity for dependable fault protection.
- DIN rail mounting for quick installation in electrical enclosures.
Key Features
- ABB S200MT miniature circuit breaker series.
- 8 A nominal current rating.
- 3 protected poles plus neutral.
- K type tripping curve for inductive loads.
- Thermal tripping mechanism for overload protection.
- Electromechanical tripping mechanism for short-circuit protection.
- Current limiting class 3 performance.
- Compatible with ABB System pro M compact accessories.
Miniature circuit breakers such as the ABB S203MT-K8NA protect electrical circuits by automatically disconnecting the supply when overload 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 allows higher transient inrush currents while still providing reliable short-circuit protection. This makes the S203MT-K8NA suitable for circuits supplying motors, transformers, solenoids and other inductive equipment where nuisance tripping must be avoided during normal start-up conditions.
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.
- Motor, transformer and inductive load circuits.
- Machine building and OEM electrical systems.
