Siemens 5SY4320-6 Miniature Circuit Breaker 3P B20A 10kA SENTRON

The Siemens 5SY4320-6 is a 3-pole miniature circuit breaker from the SENTRON range, rated at 20 A with tripping characteristic B and a breaking capacity of 10 kA per EN 60898. Designed for AC networks at 400 V, it delivers overcurrent and short-circuit protection for both infrastructure and industrial applications.

Technical specifications:

• MLFB: 5SY4320-6
• Manufacturer: Siemens
• Product line: SENTRON
• Number of poles: 3 (3P)
• Tripping characteristic: B
• Rated current (AC): 20 A
• Rated voltage (AC): 400 V
• Insulation voltage (Ui): 440 V
• DC rated voltage: 60 V (max operating 72 V)
• Breaking capacity (EN 60898): 10 kA
• Breaking capacity (IEC 60947-2): 20 kA
• DC breaking capacity (IEC 60947-2): 15 kA
• Energy limitation class: 3
• IP rating: IP20 (with connected conductors)
• Overvoltage category: 3 / Pollution degree: 3
• Power loss per pole: 2.2 W
• Mounting: DIN rail, any position
• Installation depth: 70 mm
• Dimensions (W x H x D): 54 x 90 x 76 mm
• Weight: 458 g
• Conductor cross-section (solid/stranded): 0.75 - 35 mm²
• Conductor cross-section (finely stranded with ferrule): 0.75 - 25 mm²
• Tightening torque: 2.5 - 3.5 N·m
• Operating temperature: -40°C to 70°C
• Mechanical service life: 10,000 operating cycles
• Standards: IEC/EN 60898-1, IEC/EN 60947-2, UL1077

Features and benefits:

• Halogen-free and silicon-free construction
• Touch protection (IP20) with conductors connected
• Sealable design prevents unauthorized adjustment
• Suitable for use as a main switch per EN 60204-1
• Combined top and bottom terminals for flexible cable entry
• Supplementary add-on devices can be installed

Applications:

• Overcurrent and short-circuit protection in 3-phase distribution boards
• Industrial and infrastructure switchgear panels
• Final circuit protection in commercial and industrial buildings
• Installations requiring maritime or railway certification

Compliant with IEC/EN 60898-1 and IEC/EN 60947-2. Part of the Siemens SENTRON range.

Also known as: Siemens 5SY4320-6, SENTRON 3-pole B20 MCB, Siemens 3P 20A miniature circuit breaker.