Overview
The Siemens 3RH1131-1BB40 is an IEC-rated control relay designed for auxiliary switching and control circuit applications. This 4-pole unit features 3 normally-open (NO) and 1 normally-closed (NC) contacts, making it ideal for complex logic and interlocking applications in industrial automation. The 3RH1131-1BB40 operates on 24VDC with screw-terminal connections, providing reliable switching performance in Size S00 configuration.
Key Features
- 4-Pole Configuration – 3NO + 1NC contact arrangement for flexible control logic
- 24VDC Coil Operation – Rated for 24V DC with 0.8–1.1 operating range factor
- 10A Contact Rating – 690V insulation rating for industrial voltage environments
- Screw Terminal Mounting – Direct panel or DIN-rail installation with conductor sizing 20–12 AWG
- Extended Mechanical Life – 30,000,000 mechanical operating cycles typical; 10,000,000 with auxiliary switch block
- Wide Ambient Operating Range – –25°C to +60°C rated operation; suitable for harsh factory environments
Technical Specifications
| Specification | Value |
| Manufacturer | Siemens |
| Model/Part Number | 3RH1131-1BB40 |
| Product Type | Control Relay (4-Pole Auxiliary) |
| Contact Configuration | 3 NO + 1 NC |
| Contact Rating | 10 A @ 690V insulation |
| Coil Voltage (Rated) | 24 VDC |
| Coil Power (Pull-in/Holding) | 3.2 W DC |
| Mounting Type | Screw Terminal & Snap-On |
| Conductor Size | 20–16 AWG / 12 AWG |
| Ambient Operating Temperature | –25°C to +60°C |
| Mechanical Cycle Life | 30,000,000 cycles (contactor only) |
| Series | Siemens SIRIUS 3RH10 |
| Installation Altitude | Max 2,000 m above sea level |
| Condition | New – No Box |
Typical Applications
The 3RH1131-1BB40 is commonly used in:
- Motor starter interlocking and auxiliary switching circuits
- PLC-based automation control systems requiring proven relay logic
- Equipment safety circuits and dual-channel control configurations
- Industrial machinery with 24VDC control architecture
- Factory automation, packaging equipment, and material handling systems
- Replacement in legacy Siemens SIRIUS control relay installations
Compatibility & Replacements
Compatible With
- 24VDC industrial control circuits and power distribution systems
- Siemens SIRIUS 3RH10-series auxiliary switch platforms
- DIN-rail and screw-terminal panel mounting configurations
- IEC 61346-2 industrial control installations
- Systems requiring proven mechanical relay logic for high-reliability applications
Replaces / Drop-In Replacement For
Verify compatibility with your system integrator before ordering. The 3RH1131-1BB40 is a discontinued Siemens product; contact Siemens technical support or authorized distributors to confirm suitable modern replacements from the current SIRIUS control relay or auxiliary switch block portfolio.
Works With
- Siemens S7-200, S7-300, S7-400, and S7-1200 PLC control inputs
- Traditional hardwired relay logic and electromechanical automation circuits
- DC 24V uninterruptible control power supplies
- Auxiliary switch blocks and contactor extensions in SIRIUS product family
