Siemens 5SJ4120-7HG40 Miniature Circuit Breaker 1P C20A 14kA SENTRON

The Siemens 5SJ4120-7HG40 is a SENTRON miniature circuit breaker: 1 pole, tripping characteristic C, rated at 20 A. It delivers short-circuit protection up to 14 kA per UL 1077 and CSA C22.2 No.235, and 10 kA per EN 60898. Suitable for infrastructure and industry applications, it mounts on a standard DIN rail in a single 18 mm modular width.

Technical specifications:

• MLFB: 5SJ4120-7HG40
• Manufacturer: Siemens
• Product line: SENTRON
• Poles: 1 (1P), tripping characteristic C
• Rated current: 20 A at 40°C (18.8 A at 50°C, 17.6 A at 60°C)
• Insulation voltage (Ui): 440 V AC
• Operating voltage AC (UL 489 / CSA C22.2 No. 5-02): 120 V max
• Operating voltage DC: 60 V max
• Breaking capacity (Icn, UL 1077 / CSA C22.2 No.235): 14 kA
• Breaking capacity (EN 60898): 10 kA; (IEC 60947-2): 15 kA
• Instantaneous trip setting (Ii): 7.5 x In
• Power loss per pole: 2.4 W
• IP rating: IP 0 (handle range)
• Overvoltage category: 3 / Degree of pollution: 3
• Operating temperature: -25°C to +55°C
• Storage temperature: -40°C to +75°C
• Mounting: Standard DIN rail, any position
• Dimensions (WxHxD): 18 x 90 x 70 mm
• Weight: 163 g
• Conductor cross-section: 0.75 mm² to 25 mm² (finely stranded with core end processing)
• Terminal tightening torque: 3.5 N·m
• Mechanical service life: 10,000 operating cycles

Features and benefits:

• Equal polarity connection for simplified wiring in UL 489-listed installations
• Halogen-free and silicon-free construction
• Sealable design for tamper-evident installations
• Touch-protected terminals as standard
• Combined top and bottom terminals accept conductors from 0.75 mm² to 25 mm²
• Compatible with supplementary devices for extended functionality

Applications:

• Branch circuit protection in UL 489-listed distribution boards at 120 V AC
• DC control circuit protection in panels and battery-backed systems up to 60 V
• Industrial and infrastructure switchgear and panel building
• Equipment protection in commercial and public buildings

Compliant with IEC/EN 60947-2 and UL 489. Part of the Siemens SENTRON range.

Also known as: Siemens 5SJ4120-7HG40, SENTRON 5SJ4 miniature circuit breaker, Siemens 5SJ4 1P C20A MCB.