Description
WOODWARD 9905-971 LINKNet 16-Channel Discrete Input Module
1. Product Description
The WOODWARD 9905-971 is a high-performance discrete input module designed for industrial automation and control systems. As part of the LINKNet series, it supports RS-485 communication and enables real-time monitoring of digital signals from sensors, switches, and other field devices. With 16 independent channels, this module efficiently captures on/off states and transmits data to PLCs, DCS systems, or 上位机，ensuring reliable operation in challenging environments such as power generation, petrochemical, and manufacturing industries. Its robust design and flexible configuration make it ideal for applications requiring precise signal acquisition and seamless integration.
The WOODWARD 9905-971 is a high-performance discrete input module designed for industrial automation and control systems. As part of the LINKNet series, it supports RS-485 communication and enables real-time monitoring of digital signals from sensors, switches, and other field devices. With 16 independent channels, this module efficiently captures on/off states and transmits data to PLCs, DCS systems, or 上位机，ensuring reliable operation in challenging environments such as power generation, petrochemical, and manufacturing industries. Its robust design and flexible configuration make it ideal for applications requiring precise signal acquisition and seamless integration.
2. Key Technical Parameters
| Parameter | Specification |
|---|---|
| Channels | 16 discrete inputs |
| Input Type | Dry contacts (NO/NC) or 0–24 VDC |
| Power Supply | 24 VDC |
| Communication | RS-485 (Modbus RTU compatible) |
| Isolation | Optocoupler isolation (2.5 kV) |
| Response Time | <10 ms |
| Operating Temperature | -40°C to +70°C |
| Mounting | DIN rail |
| Dimensions | 160 mm × 100 mm × 60 mm |
WOODWARD 9905-971
3. Advantages and Features
- High Reliability: Built with industrial-grade components and surge protection, the 9905-971 withstands voltage spikes and electromagnetic interference, ensuring stable performance in harsh conditions.
- Flexible Configuration: Supports both dry contacts and voltage signals, adapting to diverse sensor types without additional hardware.
- Real-Time Monitoring: Fast response time (<10 ms) enables immediate detection of state changes, critical for safety-critical systems.
- Space-Saving Design: Compact DIN rail mount optimizes panel space while facilitating easy installation and maintenance.
- Redundancy Support: Optional dual-channel redundancy enhances system availability in mission-critical applications.
4. Application Areas and Case Studies
Industry:
Industry:
- Power Generation: Monitoring turbine auxiliary systems (e.g., valve position, pump status).
- Manufacturing: Tracking conveyor belt operations and robotic arm movements.
- Oil & Gas: Remote monitoring of wellhead sensors and pipeline safety valves.
Case Study:
A chemical plant in China integrated the WOODWARD 9905-971 to monitor 16 safety interlock switches across its production line. The module’s rapid response and noise immunity reduced false alarms by 30%, improving operational efficiency and safety.
A chemical plant in China integrated the WOODWARD 9905-971 to monitor 16 safety interlock switches across its production line. The module’s rapid response and noise immunity reduced false alarms by 30%, improving operational efficiency and safety.
5. Competitive Comparison
Compared to similar modules, the 9905-971 offers:
Compared to similar modules, the 9905-971 offers:
- Higher Channel Density: 16 channels in a compact form factor, reducing panel space by 20%.
- Wider Voltage Range: Supports 0–24 VDC inputs, eliminating the need for signal conditioning.
- Enhanced Isolation: 2.5 kV isolation surpasses industry standards for noise resistance.
6. Selection Recommendations
- Compatibility: Ensure compatibility with your PLC/DCS system’s communication protocol (e.g., Modbus RTU).
- Environmental Conditions: Verify temperature, humidity, and vibration requirements match your application.
- Scalability: For large-scale projects, consider daisy-chaining multiple 9905-971 modules via RS-485.
7. Precautions
- Wiring: Use shielded cables to minimize noise; separate high/low current circuits.
- Power Stability: Maintain a clean 24 VDC power supply to avoid voltage fluctuations.
- Firmware Updates: Regularly update firmware via WOODWARD’s official tools for optimal performance.
