Siemens 5SY17042 MCB 1P Z 4A 10kA with Auxiliary Switch 1NO

In industrial control panels and building installations, the Siemens 5SY17042 miniature circuit breaker protects circuits against overload and short circuit, while its integrated auxiliary switch signals the breaker state to a PLC or monitoring system. The 1-pole unit with Z tripping characteristic is rated for 4 A and a switching capacity of 10 kA, suitable for 230/400 V AC networks at 50/60 Hz. Mounting on a standard DIN rail (EN 60715) and screw terminals simplify installation.

Key specifications

• Number of poles: 1P
• Tripping characteristic: Z
• Rated current: 4 A
• Rated voltage: 230/400 V AC
• Rated switching capacity: 10 kA
• Frequency: 50/60 Hz
• Auxiliary switch: 1 NO (normally open)
• Mounting type: DIN rail (EN 60715)
• Terminal type: Screw terminals
• Degree of protection: IP20 (terminals), IP40 (with enclosure)
• Electrical endurance: 10,000 switching cycles
• Mechanical endurance: 20,000 switching cycles
• Ambient operating temperature: -25 to +45 °C
• Rated insulation voltage: 500 V
• Rated impulse withstand voltage: 4 kV
• Installation depth: 76 mm

Why choose it

The Z characteristic provides fast tripping for semiconductor circuits and control transformers, while the auxiliary contact enables remote status indication without additional wiring. Robust construction ensures reliable performance in demanding environments.

Ideal use cases

• Protection of control circuits in industrial machinery
• Building automation systems requiring status feedback
• Distribution boards with DIN rail mounting

Good to know

The device complies with IEC/EN 60898-1. It is designed for use in ambient temperatures from -25 °C to +45 °C.