Siemens Miniature circuit breaker, B-curve, 2-pole, 400V, 50A Part number 5SL4250-6

Product Overview

The Siemens 5SL4250-6 is the Siemens SENTRON 5SL4 Miniature Circuit Breaker, 2-pole, 50 A, B-characteristic. It is designed for overload and short-circuit protection in AC electrical installations — ideal for branch-circuit protection in residential, commercial or light industrial distribution boards and control panels.

Key Features

• 2-pole miniature circuit breaker (2P)
• Rated current: 50 A
• Tripping characteristic: B (standard type for general load and lighting circuits)
• Rated operational voltage: up to 400 V AC (multi-phase) / up to 440 V AC maximum
• Short-circuit breaking capacity: 10 kA (Icu rated) — suitable for typical distribution circuits
• Energy-limiting class 3 — helps reduce fault energy and improve protection
• Screw-type terminals — compatible with solid or stranded conductors (range: 0.75 … 25 mm²)
• Modular width: 2 units (≈ 36 mm) — fits standard DIN-rail enclosures and distribution boards
• Compact design — 90 mm height, 76 mm depth, 70 mm installation depth
• Mounting: DIN-rail or busbar mounting; any mounting position allowed

Technical Specifications

• Article Number: 5SL4250-6
• Product Series: SENTRON 5SL4 miniature circuit breakers
• Poles: 2 (two-pole)
• Rated Current (In): 50 A
• Rated Operational Voltage (AC): 230/400 V AC; up to 440 V AC max
• Breaking Capacity (Icu / Ics): 10 kA
• Tripping Curve: B-characteristic
• Conductor Size (solid / stranded): 0.75 … 25 mm²
• Terminal Tightening Torque: 2.5 … 3 N·m
• Width (modular units): 2 (≈ 36 mm)
• Dimensions (approx.): Height 90 mm, Depth 76 mm, Installation depth 70 mm
• Protection Rating: IP20 (with connected conductors)
• Ambient Operating Temperature: –25 °C … +55 °C typical (storage: –40 °C … +75 °C)
• Mechanical Service Life: ~10,000 switching cycles typical

Compliance & Certifications

• Complies with standard electrical protection requirements for miniature circuit breakers (AC supply, overload & short-circuit protection)
• Suitable for use in residential, commercial, and light-industrial electrical installations
• Compatible with standard DIN-rail busbar systems and modular distribution enclosures
• Auxiliary and accessory devices (such as fault-signalling contacts or shunt trips) can be added according to scenario requirements

Applications

The Siemens 5SL4250-6 MCB is suitable for branch-circuit protection in distribution boards for lighting, socket outlets, small motor loads or general loads. It is also commonly used in control panels, machine distribution boards, small commercial installations, residential buildings, and any application requiring a reliable, compact 50 A over-current protection device with B-characteristic tripping behavior.