Comprehensive Overview of the ABB S273-K20 Circuit Breaker

The ABB S273-K20 is a high-quality miniature circuit breaker designed for industrial and commercial applications requiring dependable overcurrent protection. With its K-curve trip characteristic, it’s ideal for protecting circuits with higher inrush currents, such as motors, transformers, and inductive loads, while still offering fast tripping under short-circuit conditions.

Key Specifications

• Model: S273-K20

• Manufacturer: ABB (Asea Brown Boveri) – SACE Series

• Poles: 3 (three-phase)

• Current Rating: 20 A

• Voltage Rating:

  • 277 V AC (single-phase)

  • 480 V AC (three-phase)

• Trip Curve: K-curve – suited for high inrush current loads

• Interrupting Capacity: 10 kA @ 480 V AC

• Mounting Type: DIN-rail (quick and secure installation)

• Protection Rating: IP20 – protection against accidental contact

• Weight: Approx. 1 lb

Features & Benefits

• Reliable Overcurrent Protection – Protects equipment and wiring from overloads and short circuits.

• K-Curve Performance – Handles 8–12 times the rated current during inrush without nuisance tripping, perfect for inductive loads.

• Compact DIN-Rail Mounting – Saves panel space and allows easy integration into existing systems.

• Safety-Focused Design – Finger-safe terminals and IP20 housing for safer installation and operation.

• Durable Construction – Built with ABB’s industrial-grade materials for long service life in demanding environments.

Typical Applications

• Motor control circuits

• Transformers and inductive load protection

• HVAC equipment

• Lighting control systems with high start-up surges

• Industrial machinery and automation panels

Why Choose ABB’s S273 Series

ABB’s S273 series breakers are engineered to deliver consistent, reliable performance, meeting strict IEC and UL standards. The combination of compact design, robust build quality, and application-specific trip curves ensures long-term protection for mission-critical electrical systems.

Documents

Spec Sheet

Products Sheet

Advanced Electrical Protection with ABB S273-K20

The ABB S273-K20 is a premium 3-pole circuit breaker designed for reliable electrical protection in various residential and commercial setups. With a rated current of 20 amperes and a K-curve tripping characteristic, it effectively safeguards electrical circuits against overloads and short circuits. This breaker ensures selective coordination in electrical systems, minimizing downtime and enhancing safety. ABB's trusted engineering delivers consistent performance, making the S273-K20 an ideal choice for critical power management applications.

Robust Design and High-Quality Components

Constructed with durable materials, the ABB S273-K20 boasts robust mechanical and thermal protection features. Its compact 3-pole design simplifies installation in standard electrical panels, while the precise K-curve allows for better handling of motor startup currents. The breaker’s design complies with international standards, offering high resistance to electrical faults and environmental stressors. This ensures long-term reliability and reduces maintenance costs, meeting the rigorous demands of modern electrical infrastructures.

Easy Integration and Versatile Application

The ABB S273-K20 circuit breaker integrates seamlessly with ABB's modular system components, providing flexible installation options. It supports a wide range of electrical applications, from lighting circuits to motor protection, delivering consistent tripping performance tailored to specific load conditions. Thanks to its straightforward handling and clear marking, technicians can install and service the device with ease. This versatility combined with ABB’s quality assurance makes the S273-K20 a dependable solution for diverse power protection needs.