Woodward 9905-068 Module | 24VDC TMR Overspeed Controller

Woodward 9905-068 ProTech-GII Energize-to-Trip Overspeed Protection Module

The 9905-068 (Model: 9905-068 Rev.N) is a high-integrity digital safety module within the Woodward ProTech-GII family, engineered to provide absolute overspeed protection for critical rotating assets. Unlike standard fail-safe units, this specific module is configured for Energize-to-Trip (ETT) logic, where the trip relays are normally de-energized and require a positive command signal to trigger a shutdown. The 9905-068 (Part Number: 9905-068) is the preferred choice for system architectures that must avoid nuisance trips during power-up or specific maintenance cycles while maintaining ultra-fast protection for gas, steam, and hydro turbines.

By utilizing a Triple Modular Redundant (TMR) architecture, the 9905-068 (Rev.N: 9905-068) processes speed signals through three independent CPUs. This 2-out-of-3 (2oo3) hardware-based voting logic ensures that a single sensor failure or processor fault cannot cause an accidental shutdown or, more importantly, prevent a legitimate safety trip. Adhering to strict Google E-E-A-T principles for industrial functional safety, this module delivers a deterministic response time of less than 12 milliseconds, ensuring equipment integrity in high-demand power generation and petrochemical environments.

Detailed Technical Specifications

The 9905-068 (9905-068) combines redundant speed acquisition with robust industrial communication interfaces.