Why Choose the ABB S203-D20 Miniature Circuit Breaker?
The ABB S203-D20 is a reliable three-pole miniature circuit breaker (MCB) designed to protect electrical circuits and connected equipment against overloads and short circuits. As part of the proven ABB System pro M compact S200 series, it provides dependable protection for commercial, industrial and building-services electrical installations.
The circuit breaker combines a delayed thermal tripping mechanism for overload protection with an electromechanical tripping mechanism for rapid short-circuit protection. Its D-curve tripping characteristic is particularly suitable for circuits supplying equipment with high starting or inrush currents, including motors, transformers, solenoids and industrial machinery.
With a rated current of 20 A, a three-pole configuration and a rated short-circuit capacity of 6 kA at 400 V AC, the S203-D20 is ideal for protecting three-phase electrical loads. Its compact modular design enables straightforward installation on a standard 35 mm DIN rail inside distribution boards, switchboards and industrial control panels.
Key Advantages
- Reliable overload and short-circuit protection for three-phase circuits.
- 20 A rated current for industrial and commercial electrical loads.
- D-curve tripping characteristic suitable for equipment with high inrush currents.
- 6 kA short-circuit breaking capacity at 400 V AC.
- Clear red and green contact-position indication for easier inspection.
- Compact DIN rail format simplifies installation in electrical panels.
Key Features
- ABB System pro M compact S200 series.
- Three-pole miniature circuit breaker.
- 20 A rated current.
- D tripping characteristic.
- 400 V AC rated operational voltage according to IEC/EN 60898-1.
- 6 kA rated short-circuit capacity at 400 V AC.
- Thermal overload and electromechanical short-circuit tripping mechanisms.
- Current-limiting design helps reduce the effects of fault currents.
- Clear red ON and green OFF contact-position indication.
- Compact mounting on a standard TH35 DIN rail.
Reliable Protection for High-Inrush Electrical Loads
Miniature circuit breakers such as the ABB S203-D20 automatically disconnect the electrical supply when an overload or short circuit is detected. The thermal tripping mechanism responds to sustained excess current, while the electromechanical mechanism provides rapid disconnection during severe short-circuit conditions.
The D-curve characteristic allows the circuit breaker to tolerate higher momentary current peaks than standard B-curve or C-curve devices. This makes the S203-D20 suitable for motors, transformers and other inductive loads that can draw a substantial current during start-up without compromising reliable circuit protection.
Typical Applications
- Three-phase motors and industrial machinery.
- Transformers and inductive electrical loads.
- Automation equipment and production systems.
- Industrial control panels and switchgear assemblies.
- Commercial and industrial distribution boards.
- Pumps, compressors and ventilation equipment.
