56681 Murrelektronik Terminal Module IP20 Automation Stainless Anti Vibration Connector

The Murr Elektronik 56681 MICO-Safety Relay Module is a DIN-rail mountable safety interface designed for Category 3/PLd safety circuits per ISO 13849. This compact (12.5mm width) solid-state device integrates dual-channel safety inputs and 3 semiconductor safety outputs (OSSDs) to monitor emergency stops, safety gates, or light curtains. Featuring galvanically isolated 24VDC operation (±25% tolerance) and IP20 protection, it withstands industrial noise/vibration while enabling SIL 2 safety integrity without PLC programming. The integrated diagnostic LEDs provide instant fault localization for wiring errors or device failures. Ideal for machinery requiring space-optimized safety solutions with ≤100ms response time compliance.

Critical safety parameters:

• Safety Rating: PLd Cat.3 (ISO 13849-1), SIL 2 (IEC 62061)
• Inputs: 2 dual-channel (24VDC, sink/source, cross-wire detection)
• Outputs: 3 PNP OSSDs (0.5A @ 24VDC each, short-circuit protected)
• Response Time: ≤60ms (E-stop detection to output shutdown)
• Max. Switching Frequency: 100Hz
• Diagnostic Coverage (DCavg): >97%
• Operating Voltage: 20.4-28.8VDC
• Ambient Temperature: -25°C to +60°C (70°C max with derating)
• Connection: Spring-clamp terminals (0.25-2.5mm²)
• MTTFd: >100 years (EN ISO 13849-1)
• Standards: IEC 60204-1, UL 508

Space-constrained safety integration:

• Packaging Machinery: Conveyor E-stop monitoring with muting circuit control
• CNC Equipment: Guard door interlocking for tool-change areas
• Material Handling Robots: Collaborative cell safety gate supervision
• Plastic Injection Molding: Clamp zone access prevention
• Automated Assembly Lines: Two-hand control station verification
• Test Benches: Emergency cutoff for high-voltage equipment

Reduces safety panel space by 70% versus traditional relay stacks.

Innovative safety engineering:

• Ultra-Slim Profile: 12.5mm width fits nano-panels (saves 80% vs. relays)
• Auto-Diagnostics: Continuously monitors wiring shorts/open circuits
• Global Voltage Compatibility: Operates down to 20.4VDC for voltage-drop resilience
• Plug-and-Play: Pre-wired function blocks (no coding required)
• Transient Immunity: 4kV surge protection (EN 61000-4-5 Level 3)
• Multi-Module Synchronization: Up to 8 units cascade via bus connectors
• Retrofit Ready: Direct replacement for electro-mechanical safety relays

Advanced monitoring logic:

• Cross-Circuit Detection: Identifies faults between input channels
• Configurable Reset Logic: Auto/manual reset via DIP switch selection
• Start Interlock: Prevents automatic restart after power loss
• Output Pulse Testing: Automated self-test of OSSD switching
• Status Feedback: Dedicated N/O auxiliary contact for PLC signaling
• Time Delays: Built-in 0.1-10s adjustable startup delay
• Short-Circuit Resilience: PTC-based output current limiting

Includes manual test button for safety circuit validation pre-commissioning.