Siemens 5SY4120-6 Miniature Circuit Breaker 1P B20A 10kA SENTRON

The Siemens 5SY4120-6 (MLFB: 5SY4120-6) is a SENTRON miniature circuit breaker rated at 20 A with a 1-pole, B-tripping characteristic for AC circuits up to 230/400 V. It provides short-circuit and overload protection with a breaking capacity of 10 kA according to EN 60898 and 20 kA according to IEC 60947-2.

Technical specifications:

• MLFB: 5SY4120-6
• Manufacturer: Siemens
• Product line: SENTRON
• Number of poles: 1 (1P)
• Tripping characteristic: B
• Rated current: 20 A
• Rated voltage (AC): 230 V (single-phase), 400 V (multi-phase)
• Insulation voltage (Ui): 440 V AC
• DC voltage: rated 60 V, maximum 72 V
• Breaking capacity: 10 kA (EN 60898), 20 kA (IEC 60947-2), 15 kA DC (IEC 60947-2)
• Energy limitation class: 3
• Overvoltage category: 3
• Degree of pollution: 3
• IP rating: IP20 (with connected conductors)
• Power loss per pole: 2.2 W
• Mechanical service life: 10,000 operating cycles (typical)
• Conductor cross-section (solid/stranded): 0.75-35 mm²
• Tightening torque: 2.5-3.5 N·m
• Dimensions (WxHxD): 18 x 90 x 76 mm (installation depth 70 mm)
• Weight: 165 g
• Operating temperature: -40 °C to +70 °C
• Frequency: 50/60 Hz
• Mounting: DIN rail, any position
• Standards: IEC/EN 60898-1, IEC/EN 60947-2, UL 1077

Features and benefits:

• Touch-protected terminals with combined top and bottom terminal connections
• Halogen-free and silicon-free construction
• Sealable design for tamper protection
• Compatible with supplementary add-on devices for extended functionality
• Suitable for both infrastructure and industrial applications
• Approved for maritime and railway applications

Applications:

• Overload and short-circuit protection of final circuits in residential and commercial distribution boards
• Protection of single-phase AC loads in industrial control panels
• DC circuit protection in battery-backed systems up to 72 V
• Use as a main switch in machinery in accordance with EN 60204-1

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

Also known as: Siemens 5SY4120-6, Siemens SENTRON MCB 1P B20A, Siemens miniature circuit breaker 5SY4.