Description
The Siemens 3RK1402-0BE00-0AA2 is a decentralized digital I/O expansion module from the SIRIUS AS-Interface (AS-i) SlimLine S22.5 product family. This compact, 22.5 mm wide DIN-rail module interfaces local hardware elements directly onto an AS-i fieldbus network. It features two digital inputs optimized for binary 2-wire or 3-wire PNP sensors alongside two independent electromechanical relay outputs for switching physical actuator lines.
Commercial and Lifecycle Status
- Condition: New Surplus (In Original Packaging) or Refurbished (Tested)
- Availability: In Stock / Legacy Inventory
- Warranty: 12-Month Comprehensive Warranty
- Product Lifecycle Notice: This part number is categorized as a phased-out/legacy product by Siemens. While active series production has transitioned, warehouse reserves are maintained to support active plant operations and legacy control cabinet replacements.
- Pricing Note: Spot pricing is subject to current market availability. Contact our sales department directly to receive a firm, contract-specific quote.
Technical Specifications
| Parameter | Value / Specification |
| Manufacturer | Siemens |
| Product Series | SIRIUS AS-Interface SlimLine |
| Model Number | 3RK1402-0BE00-0AA2 |
| Module Topology | S22.5 Digital 2DI / 2RQ (Relay Output) |
| Slave Profile Type | Standard Slave configuration |
| Number of Digital Inputs | 2 |
| Input Sensor Type | PNP Transistor, 2-wire or 3-wire proximity compatible |
| Input Current (State 1) | 5 mA |
| Number of Digital Outputs | 2 |
| Output Switching Element | Electromechanical Relay (Dry contact) |
| Relay Switching Voltage | Up to 230 V AC / 24 V DC |
| Continuous Relay Current | 6 A maximum per output channel |
| Connection Technology | Screw-type terminal blocks |
| Enclosure Rating | IP20 conforming to IEC 60529 |
| Mounting Options | 35 mm standard DIN rail or wall mount via push-in lugs |
| Operating Temperature | −25 to +70 °C (−13 to +158 °F) |
| Dimensions (H x W x D) | 102 x 22.5 x 86 mm |
System Integration and Electrical Wiring
Sensor Interface Mechanics
The two digital inputs rely on internal power routing derived from the yellow AS-i ribbon cable. The sensor inputs are designed for standard PNP sourcing configurations. When installing 3-wire proximity sensors, terminate the power, return, and signal lines directly into the designated screw terminals. The module provides short-circuit protection and sensor supply monitoring internally to protect the network chip from terminal damage.
High-Capacity Relay Outputs
Unlike solid-state transistor variants, the 3RK1402-0BE00-0AA2 uses heavy-duty electromechanical relays capable of switching up to 6 A at 230 V AC. This eliminates the requirement for intermediate interposing relays when driving medium-sized AC solenoids, small single-phase motors, or indicator beacons.
Network Architecture and Configuration
Because the module maps as a standard AS-i slave device, it occupies a full address on the network run. Addressing parameters are injected via standard handheld programming devices or mapped through Siemens STEP 7 / TIA Portal hardware managers.
Installation Constraints and Maintenance Best Practices
- Relay Isolation: Ensure that high-voltage AC cables (up to 230 V AC) feeding the relay contacts are routed away from low-voltage AS-i bus lines. Physical segregation inside wire ducts minimizes capacitive coupling and high-frequency communication noise.
- Arc Suppression: When switching inductive AC or DC loads with the onboard relays, connect external RC snubber networks (for AC loops) or freewheeling diodes (for DC loops) directly across the field device. Unsuppressed inductive counter-EMF spikes cause contact arcing, welding the internal relay contacts shut.
- Terminal Torque Management: Tighten all screw terminals using a calibrated driver. Loose screw terminal connections form high-resistance pathways under vibration, leading to intermittent signal dropouts and localized thermal loading.
