Product Overview

The Woodward 9905-970 (Revision K) functions as a specialized distributed temperature acquisition node within the LinkNet I/O family. This module interfaces directly with six independent 3-wire $100\Omega$ Platinum RTDs, converting analog resistance signals into precise digital data for turbine and industrial engine control systems. It communicates via the Woodward proprietary LinkNet serial bus, allowing seamless integration with MicroNet and Atlas control platforms. By offloading signal conditioning to the network edge, the 9905-970 reduces wiring complexity and enhances system modularity in mission-critical thermal monitoring applications.

Condition: This unit is 100% Brand New, original Woodward factory stock.

Technical Specifications

The 9905-970 Rev K incorporates advanced linearization logic to ensure sub-degree measurement accuracy across its full operating range.

Engineering Advantages

• Superior Noise Immunity: The Revision K hardware specifically addresses electromagnetic interference (EMI) common in power generation environments. It maintains stable readings even when installed near high-voltage equipment or variable frequency drives.

• Optimized 3-Wire Lead Compensation: The module automatically compensates for lead wire resistance. This ensures that the distance between the RTD sensor and the 9905-970 module does not degrade temperature measurement accuracy.

• Distributed Architecture Benefits: By utilizing the LinkNet serial bus, engineers can mount this module closer to the engine or turbine. This significantly reduces the cost and weight of expensive shielded multi-core cabling back to the central control room.

• Extreme Environment Durability: The ruggedized housing and components support an expansive operating temperature range (–40°C to +70°C). This allows for reliable performance in unconditioned enclosures or harsh outdoor industrial sites.

• Deterministic Data Transmission: Unlike standard Ethernet protocols that may suffer from collisions, the LinkNet protocol ensures consistent, time-stamped data delivery for high-speed control loops.

FAQs

• What is the significance of the "Rev K" designation?

  Revision K represents Woodward's enhanced hardware design, which provides superior signal stability and better component longevity compared to earlier revisions (like Rev E or G). It is backward compatible with systems using older 9905-970 versions.

• Does this module support 2-wire or 4-wire RTDs?

  The 9905-970 is specifically optimized for 3-wire $100\Omega$ Platinum RTDs. While 2-wire sensors can be connected by jumping the terminals, 3-wire configurations are required to utilize the module's lead-wire compensation circuitry for maximum accuracy.

• How do the onboard LEDs assist in troubleshooting?

  The module features dedicated LEDs that provide immediate visual feedback. The "Network" LED confirms active communication with the LinkNet master, while the "Status" LED alerts technicians to internal hardware faults or sensor out-of-range conditions.

• Is calibration required upon installation?

  Woodward factory-calibrates each 9905-970 module. Because it uses digital linearization and high-precision reference resistors, it generally requires no field calibration during initial commissioning.