Why Choose the ABB S203MT-Z4NA Miniature Circuit Breaker?
The ABB S203MT-Z4NA is a compact and dependable miniature circuit breaker (MCB) designed for 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 applications where reliable circuit protection, compact installation and fast fault response are required.
This circuit breaker features a Z curve tripping characteristic, making it suitable for sensitive circuits where rapid disconnection is needed during short-circuit conditions. 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 4 A and a 3-pole plus neutral configuration, the ABB S203MT-Z4NA is suitable for three-phase circuits where the neutral conductor must switch together with the protected phases. Its DIN rail mounting format allows straightforward installation inside electrical control panels, distribution boards, switchgear assemblies and machinery enclosures.
Key Advantages
- Compact miniature circuit breaker for circuit protection.
- 4 A rated current for low-current electrical circuits.
- 3-pole plus neutral configuration for three-phase systems with switched neutral.
- Z curve tripping characteristic for rapid short-circuit response.
- 10 kA breaking capacity for dependable protection in demanding installations.
- DIN rail mounting for quick installation in electrical enclosures.
Key Features
- ABB S200MT miniature circuit breaker series.
- 4 A nominal current rating.
- 3 protected poles plus neutral.
- Z type tripping curve for sensitive circuit protection.
- 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-Z4NA 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 Z curve characteristic provides fast magnetic tripping at lower fault current levels than standard MCB curves, making this device suitable for sensitive equipment and circuits where rapid disconnection is required. Its 3-pole plus neutral layout also supports installations where the neutral conductor must be switched together with the protected phases.
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.
- Protection of sensitive electronic equipment.
- Machine building and OEM electrical systems.
