The Woodward 9907-345 is a high-performance overspeed protection system designed specifically for critical rotating machinery such as steam turbines, gas turbines, and industrial engines. This model belongs to the ProTech-GII Series, known for its reliability, safety compliance, and fast reaction times.

The system functions as a triple-redundant (2-out-of-3 voting) speed monitoring and protection unit, ensuring immediate shutdown of machinery in case of detected overspeed events. It is primarily used in safety-critical operations, where a failure in speed control could lead to severe mechanical damage or endanger human lives.

Built with robust hardware and advanced software algorithms, the 9907-345 is certified for use in hazardous and SIL-rated environments. The unit features three isolated speed-sensing channels, redundant power supplies, configurable trip parameters, and programmable relays for safe, deterministic response to over-speed conditions.

Product Specifications

Product Applications

The 9907-345 Overspeed Protection System is ideally suited for use in environments that demand high reliability and quick response to overspeed events. Some typical applications include:

• Steam turbines in power generation plants

• Gas turbines in oil & gas compression stations

• Reciprocating engines in marine propulsion systems

• Compressor trains and turbo expanders

• Standby generators in hospitals and data centers

• Process-critical rotating equipment in chemical and refining industries

Product Advantages

• Triple Redundancy: The 2-out-of-3 voting architecture ensures higher integrity and fault tolerance, reducing false trips.

• SIL 3 Certified: Designed and certified for Safety Instrumented Systems (SIS) in compliance with IEC 61508.

• Fast Response: Acts in under 40 ms upon detecting overspeed, preventing damage to machinery.

• Flexible Configuration: Allows field programmability via onboard display or USB-based upload.

• Industrial-Grade Design: Operates in extreme conditions and harsh industrial environments.

• Redundant Power Inputs: Dual power inputs ensure continuous operation during primary power failure.

• Diagnostics and Alerts: Built-in LED diagnostics and Modbus communication for real-time monitoring.

• Secure Operation: Password-protected settings and event logging for system integrity and auditing.

Frequently Asked Questions (FAQ)

1. What type of turbines is the Woodward 9907-345 suitable for?

   It is designed for both steam and gas turbines, as well as industrial engines requiring precise overspeed protection.

2. What is the power supply requirement?

   The system operates on 18–32 VDC with dual redundant inputs for enhanced reliability.

3. Does it support digital communication?

   Yes, it supports Modbus RTU via an RS-485 interface.

4. What is the trip mechanism used?

   It uses a 2-out-of-3 voting mechanism based on three speed channels to determine a valid overspeed trip.

5. Can I configure the unit in the field?

   Yes, it can be configured using the front panel interface or via a USB upload.

6. Is this model certified for safety applications?

   Yes, it is SIL 3 certified under IEC 61508 for use in Safety Instrumented Systems.

7. What is the typical response time?

   The system reacts to overspeed conditions in less than 40 milliseconds.

8. Is the front panel weatherproof?

   Yes, it has a NEMA 4X / IP66-rated front panel, suitable for outdoor and washdown environments.

9. What is the operating temperature range?

   The unit operates reliably from -40°C to +70°C.

10. What happens if one speed sensor fails?

    The system continues to operate using the remaining two channels, and diagnostics will alert the operator of the failure.