Description
Woodward 8237-2597
Technical Specifications
- Part Number: 8237-2597
- Mounting Style: Bulkhead Mount
- Power Configuration: High Voltage / High Voltage (HV/HV) power input
- Relay Architecture: Voted Relays (2-out-of-3 voting logic)
- Safety Certification: IEC 61508 SIL-3 certified
Functional Features
- Triple Modular Redundancy: Utilizes a 2oo3 voting architecture to ensure high reliability, preventing both spurious trips and failure-to-trip scenarios.
- MPU Verification: Features specialized open-wire detection circuits to verify sensor connections before startup and continuous stall detection logic during operation.
- Automatic Testing: Supports optional periodic automatic overspeed testing using internal frequency generators to validate system health without mechanical stress.
- Online Maintenance: Allows for hot-swapping of individual modules while the turbine remains online and operating normally.
Application Scenarios
Extensively deployed in steam, gas, and hydro turbines, as well as large reciprocating engines in power generation and petrochemical facilities requiring maximum safety integrity.
Performance Parameters
- Response Time: Extremely fast response time of 12 milliseconds to initiate a trip.
- Speed Range: Capable of accurately measuring and protecting equipment across a wide range from 0.5 to 32,000 RPM.
Material Composition
Housed in a ruggedized industrial enclosure featuring a special conformal coating that provides long-term protection against H2S and SO2 gas erosion, complying with IEC 721-3-3 Class 3C2.
Structural Characteristics
- Modular Design: Plug-and-play底板 (backplane) design facilitates rapid module replacement.
- User Interface: Front panel equipped with LEDs for clear indication of Unit Tripped, Unit Alarm, and Module Health status.
Working Principle
The device continuously monitors signals from Magnetic Pickup Units (MPUs). Three independent processors calculate the speed; if two or more processors detect a speed exceeding the predefined safe threshold, the voting logic instantly energizes the trip relays to close the turbine’s emergency stop valves.
Installation Requirements
- Mounting: Must be securely mounted using the bulkhead configuration to ensure proper heat dissipation and mechanical stability.
- Sensor Gap: MPU sensors must be installed with a precise air gap (typically 0.25 to 1.02 mm) from the gear teeth to ensure valid signal amplitude.
Usage Precautions
- Wiring: Do not use speed sensing from auxiliary shafts with mechanical backlash, as this can cause false tripping.
- Maintenance: Always follow the specific lockout/tagout procedures and utilize the Woodward ProTech Configuration Tool (PCT) for parameter adjustments.
