Siemens 5SY42087 SENTRON 5SY4 MCB 2P C 8A 400V 10kA DIN Rail Miniature Circuit Breaker

The Siemens 5SY42087 is a high-quality miniature circuit breaker (MCB) from the SENTRON 5SY4 series, designed for reliable overcurrent protection in electrical installations. With 2 poles, C tripping characteristic, rated current 8 A, and rated voltage 400 V AC, it ensures safe operation in residential, commercial, and industrial applications. Its compact design and 70 mm installation depth make it ideal for DIN rail mounting.

Advantages

This MCB offers robust protection with a breaking capacity of 10 kA, complying with IEC 60898-1. The C characteristic is suitable for moderate inrush currents, typical for lighting and general loads. Screw terminals allow secure connection of conductors up to 35 mm². With an IP20 front protection and wide operating temperature range (-25 to +55 °C), it performs reliably in various environments.

Suitable for

• Overcurrent protection in distribution boards
• Lighting circuits, socket outlets, and small appliances
• Commercial and industrial electrical systems
• DIN rail mounting in switchgear

Key specifications

• Product Type: Miniature Circuit Breaker (MCB)
• Series: SENTRON 5SY4
• Number of Poles: 2P
• Tripping Characteristic: C
• Rated Current: 8 A
• Rated Voltage (AC): 400 V
• Rated Short-Circuit Breaking Capacity (Icn): 10 kA
• Frequency: 50/60 Hz
• Mounting Type: DIN rail
• Connection Type: Screw terminals
• Degree of Protection (front): IP20
• Operating Temperature Range: -25 to +55 °C
• Electrical Service Life: 10,000 switching cycles
• Mechanical Service Life: 10,000 switching cycles
• Standard: IEC 60898-1
• Terminal Capacity (solid/stranded): 0.75 - 35 mm²
• Installation Depth: 70 mm
• Rated Insulation Voltage (Ui): 500 V
• Energy Limiting Class: 3
• Overvoltage Category: III

Recommendations

For optimal protection, pair this MCB with a compatible residual current device (RCD) where required. Always follow local electrical codes and installation guidelines.