The WOODWARD 9907-971 is a high-density LinkNet discrete input module designed for use with Woodward’s MicroNet and Atlas control systems. This module provides 16 independent channels for monitoring digital field contacts, such as limit switches, relay contacts, and pressure switches. As part of the LinkNet distributed I/O family, it allows for the expansion of system monitoring capabilities over a reliable serial communication network, reducing the need for extensive long-distance point-to-point wiring.

 

Product Parameters & Datasheet

The technical specifications for the WOODWARD 9907-971 are detailed in the datasheet parameters below:

• Part Number: 9907-971
• Module Type: LinkNet Discrete Input (DI)
• Number of Channels: 16 independent inputs
• Input Voltage Range: 18–32 Vdc (24 Vdc nominal)
• Input Current: Approximately 5 mA per channel at 24 Vdc
• Communication: LonTalk protocol over LinkNet twisted-pair network
• Isolation: 500 Vrms to control logic and network
• Power Consumption: 1.5 Watts maximum
• Operating Temperature: -40°C to +70°C
• Response Time: 10 ms to 100 ms (software configurable)

 

Product Technical Description

The 9907-971 module utilizes a dedicated LonTalk controller to manage data transmission across the LinkNet bus. Each of the 16 channels features internal filtering to prevent “contact bounce” from triggering false signals. The module is designed for “daisy-chain” connectivity, allowing multiple LinkNet modules (including Analog and Thermocouple types) to be linked together on a single network segment. The internal circuitry provides optical isolation between the field-side 24 Vdc signals and the sensitive network processing logic, ensuring system stability in electrically noisy industrial environments.

Application Fields

This discrete input module is widely implemented in various turbine and engine control scenarios:

• Power Generation: Monitoring breaker status, fuel valve positions, and auxiliary pump contacts.
• Oil & Gas: Interfacing with emergency shutdown (ESD) switches and flare monitors.
• Marine Automation: Tracking engine room alarms and watertight door sensors.
• Industrial Turbomachinery: Providing sequence-of-events data for gas and steam turbine control systems.

 

Country of Origin

The WOODWARD 9907-971 is manufactured in the United States of America (USA), meeting rigorous global standards for industrial automation and engine control hardware.

 

Product Usage Instructions

1. Mounting: Install the module on a standard DIN rail. Ensure it is positioned to allow for easy access to the field terminal blocks and the LinkNet network connectors.
2. Network Wiring: Connect the LinkNet “In” and “Out” ports using shielded twisted-pair cable (e.g., Belden 9461 or equivalent). Ensure the shield is continuous across the network but grounded only at the control system end.
3. Field Wiring: Connect the 24 Vdc supply to the module’s power terminals. Route the discrete input wires to the numbered terminals (1-16). Use the common return terminal provided on the module for the field contact loops.
4. Addressing: Set the unique network address for the module using the onboard rotary switches or software configuration tool, ensuring no two modules on the same LinkNet segment share an address.
5. Status Check: Upon power-up, observe the “Status” LED. A green blinking light typically indicates successful communication with the master controller, while a red light indicates a hardware or network configuration fault.