Siemens Auxiliary switch block, spring, 2NO + 2NC Part number 3RH2911-2FA22

Product Overview

The Siemens 3RH2911-2FA22 is a front-mount auxiliary switch block designed for use with Siemens SIRIUS 3RH2 contactor relays. It provides additional auxiliary contacts (2 Normally Open + 2 Normally Closed) for signalling, interlocking, feedback, and control logic expansion within industrial control systems. Compact and easy to install, it enhances functionality without increasing system footprint, making it ideal for motor control and automation applications.

Key Features

• Auxiliary switch block for SIRIUS 3RH2 contactors/relays
• Contact configuration: 2 NO + 2 NC
• Front clip-on mounting — no tools required for installation
• High switching endurance for long operational life
• Suitable for signalling, status indication, and control-circuit expansion
• Spring clamp terminals for fast and reliable wiring
• Compact design — minimal panel space required
• Rated insulation voltage up to 690 V
• Surge voltage resistance 6 kV — industrial grade robustness
• Mechanical lifespan up to ~10 million switching cycles
• Electrical lifespan approx. 200,000 operations (AC-15)

Technical Specifications

• Article Number: 3RH2911-2FA22
• Product Type: Auxiliary Contact Block
• Contact Configuration: 2 NO + 2 NC
• Mounting Type: Front-mounted onto 3RH2 series contactors
• Terminals: Spring clamp type
• Rated Insulation Voltage: 690 V
• Surge Withstand Voltage: 6 kV
• Mechanical Durability: ~10 million operations
• Electrical Durability: ~200,000 operations (AC-15)
• Protection Rating: IP20 (front)
• Net Weight: approx. 0.062 kg

Compliance & Standards

• Compatible with Siemens SIRIUS 3RH2 and selected 3RT contactor systems
• Designed and tested for industrial auxiliary switching applications
• Conforms to IEC-based contactor and control-accessory standards

Applications

Ideal for expanding auxiliary contact availability in control circuits. Common uses include feedback indication, interlocking, PLC signalling, motor starter logic, HVAC control, conveyors, pumps, fans, and general panel automation. Enables additional monitoring or logic connections without requiring external relays or redesign of the control layout.