Siemens Miniature circuit breaker, 3-pole, 400V, 10kA, 20A Part number 5SY4320-7

Product Overview

The Siemens 5SY4320-7 is a SENTRON miniature circuit breaker (MCB) designed for reliable overcurrent and short-circuit protection in low-voltage electrical installations. This 3-pole MCB features a C-characteristic tripping curve and is rated for 20 A continuous current at a supply voltage of up to 400 V AC. With a high breaking capacity of 10 kA and robust design suitable for DIN-rail mounting, the 5SY4320-7 protects circuits against overloads, faults, and short circuits in industrial, commercial, and infrastructure applications.

Key Features

• 3-pole SENTRON miniature circuit breaker
• Rated current: 20 A for AC operation
• C-characteristic tripping curve for general protection
• Rated voltage up to 400 V AC with AC/DC capability
• High breaking capacity of 10 kA per EN standards
• Suitable for DIN-rail mounting
• Quick assembly system for easy installation
• Sealable and halogen-free design
• Combined top and bottom terminals for flexible wiring
• Touch protection and safety features

Technical Specifications

• Article Number: 5SY4320-7
• Product Family: SENTRON 5SY4 Miniature Circuit Breakers
• Number of Poles: 3
• Rated Current: 20 A at AC
• Tripping Characteristic: Class C
• Rated Operational Voltage (Ue): 400 V AC
• Insulation Voltage (Ui): 440 V AC
• Breaking Capacity (Icn): 10 kA (EN standard)
• Switching Capacity: 20 kA per IEC 60947-2; 15 kA DC
• Supply Voltage Frequency: 50/60 Hz
• Mounting Type: DIN-rail quick assembly system
• Connection Terminals: Combined top and bottom screw terminals
• Connectable Conductor Cross-Section: 0.75 to 35 mm² solid or stranded
• Degree of Protection: IP20 (with connected conductors)
• Number of Width Units (W): 3
• Dimensions (H×W×D): approx. 90 × 54 × 76 mm
• Operating Temperature Range: −40 °C to +70 °C
• Storage Temperature Range: −40 °C to +75 °C
• Mechanical Service Life: approx. 20,000 switching cycles
• Overvoltage Category: III
• Pollution Degree: 3
• Weight: approx. 468 g

Compliance & Standards

• Designed and tested according to IEC/EN 60898-1 and IEC/EN 60947-2 standards
• Conforms to safety and performance requirements for miniature circuit breakers
• Suitable for use in residential, commercial, and industrial electrical distribution systems
• Halogen-free and touch-protected design complies with modern installation safety norms

Applications

The Siemens 5SY4320-7 miniature circuit breaker is used for circuit protection in electrical installations such as industrial control panels, commercial switchboards, infrastructure installations, and building distribution boards. Its C-curve characteristic makes it well suited for circuits containing general loads, lighting, receptacles, and small motor circuits requiring standard overload and short-circuit protection.