Siemens Circuit breaker, 3-pole, B-curve, 20A, 10kA Part number 5SY4320-6

Product Overview

The Siemens SENTRON 5SY4320-6 is a three-pole miniature circuit breaker (MCB) designed for reliable protection of final circuits in industrial and commercial installations. It features a B-curve tripping characteristic, 20 A rated current, and a high breaking capacity of 10 kA at 400 V AC. With compact depth (D = 70 mm), DIN-rail mounting, and robust mechanical endurance, it integrates easily into distribution boards and control panels.

Key Features

• Rated Current: 20 A (B-curve)
• Poles: 3-pole for three-phase circuits
• Breaking Capacity: 10 kA at 400 V AC
• Operating Voltage: 230/400 V AC; 72 V DC (per pole)
• Compact Form: Depth 70 mm for space-efficient panels
• Terminals: Screw clamp, wide conductor range
• Mounting: 35 mm DIN-rail (EN 60715)
• Durability: ~10,000 mechanical switching operations
• Safety Design: Overvoltage category III; pollution degree 3

Technical Specifications

• Product Series: SENTRON 5SY4
• Article Number: 5SY4320-6
• Trip Characteristic: B
• Rated Voltage (AC): 230/400 V
• Rated Insulation Voltage (Ui): 440 V
• Rated DC Voltage: 72 V DC
• Rated Short-Circuit Breaking Capacity: 10 kA (at 400 V AC)
• Number of Poles: 3
• Endurance (Mechanical): ~10,000 operations
• Protection Class: IP20 (terminals finger-safe)
• Ambient Operating Temperature: –25 °C to +45 °C
• Dimensions: Depth 70 mm (DIN-rail height/width per standard module spacing)
• Conductor Size (typ.): ~1…25 mm² (screw clamp)

Compliance & Certifications

• Standards: EN 60898 (MCBs), UL 1077 / CSA C22.2 No. 235 (supplementary protector)
• CE Marking: Conforms to applicable EU directives
• RoHS: Compliant (hazardous-substance restricted)
• Product Class: Low-voltage miniature circuit breaker for distribution and control

Applications

Ideal for branch-circuit protection in distribution boards, control panels, and machine control wiring. Commonly used for lighting and receptacle circuits, auxiliary loads, and general three-phase final circuits requiring B-curve protection and 10 kA breaking capacity.