Description

Woodward 8237-2600

I. Basic Information

Model：8237-2600

Brand：Woodward

Product Line：TMR triple modular redundant overspeed safety protection device of ProTech-GII series, SIL3 certified, adopting 2-out-of-3 hardware voting logic. It independently monitors rotating machinery speed and acceleration, provides hard trip protection for turbines and compressors, supports online maintenance, automatic periodic protection test and Modbus remote monitoring, serving as the final safety barrier of ETS/SIS safety instrument system in power, petrochemical and oil & gas industries.

Product Positioning

8237-2600 adopts three fully isolated hardware channels to avoid common-mode faults, compatible with reluctance and Hall speed sensors, integrates overspeed and over-acceleration dual protection, sensor fault detection, local HMI parameter configuration and SOE event recording functions. It can realize hot-swap single-channel maintenance under unit operating condition, meets IEC61508 functional safety standard, and is the core replacement spare part for upgrading and revamping legacy turbine overspeed protection systems.

Hardware Architecture

Reinforced PCB with conformal anti-corrosion coating, composed of six independent functional units: three-channel isolated speed sampling unit, 2oo3 hardware voting protection unit, local parameter configuration & human-machine interaction unit, full-link self-diagnosis unit, dual redundant power supply protection unit, communication and discrete I/O interaction unit. Each channel operates independently to ensure high fault isolation and safety reliability under harsh industrial electromagnetic environment.

Mounting Specification

Wall-mounted integrated installation with hot-swappable single-channel backplane structure, fully compatible with ProTech-GII series hardware backplane. Passed IEC vibration, humidity, salt spray and EMC reliability tests, supporting plug-and-play channel replacement without field wiring modification and safety loop reconstruction.

Compatible Systems

Hardware: Dual 24VDC redundant power supply, reluctance/Hall speed sensors, shielded signal cables, ETS trip solenoid valve loop, DCS/SIS connection terminals;
Tools: Woodward PCT configuration software, speed signal calibrator, insulation multimeter;
Upper Platforms: Plant SIS safety system, SCADA monitoring platform, fault recorder, SOE event server;
Industries: Thermal & combined cycle power plant, hydropower station, petrochemical compressor station, oil & gas pipeline unattended automation system.

Product Characteristics

SIL3 safety certified 2oo3 TMR redundant architecture eliminates false trip and fail-to-trip risks caused by single-point faults.
12ms hardware-level fast trip response, completely independent of main control system to prevent rotating machinery runaway accidents.
Dual protection of overspeed + over-acceleration effectively makes up for the protection blind spot of single speed monitoring.
Online channel replacement and automatic periodic protection test meet the regular verification requirements of functional safety systems.
Local SOE event storage with millisecond timestamp provides reliable data support for accident traceability and safety compliance filing.
Conformal coating rugged design adapts to high humidity, dust, corrosion and strong electromagnetic interference industrial scenarios for long-term continuous operation.

II. Technical Specifications

2.1 Electrical Parameters

Power Supply: Dual independent 18~32VDC redundant DC power supply, total power consumption ≤35W
Protection: Reverse polarity, overvoltage, undervoltage, overcurrent lockout protection, ±4kV ESD, ±2kV EFT surge immunity
Dielectric Withstand Voltage: 1500VAC 1min isolation withstand voltage for all signal and relay ports.

2.2 Speed & Protection Parameters

Measuring Range: 0.5~32000rpm, accuracy ±0.05%FS
Compatible Sensors: Passive MPU reluctance probe, active Hall sensor with open/short circuit fault detection
Voting Logic: 2-out-of-3 hardware voting, overspeed and acceleration dual trip protection
Trip Response Time: ≤12ms hardware loop, local/remote two reset modes
Analog Output: 4~20mA speed transmission per independent channel.

2.3 Communication & Discrete I/O Parameters

Communication: RS485 Modbus RTU protocol for multi-device bus networking
Relay Rating: 5A/250VAC, configurable NO/NC contact for trip and alarm
Digital Input: Remote trip reset, test trigger dry contact input
Event Storage: At least 1000 pieces of millisecond timestamp SOE historical events, log export supported.

2.4 Environmental Specifications

Operating Temperature: 0℃ ~ +65℃; Storage: -40℃ ~ +85℃
Humidity: 5%~95%RH non-condensing, anti-sulfur and salt mist corrosion
Vibration Standard: IEC 60068-2-6, 1G continuous vibration resistance
Protection Grade: Front panel IP54, internal PCB IP20.

2.5 Mechanical Parameters

Mounting: Wall-mounted integrated installation, single-channel hot-swappable design
PCB Process: Flame-retardant FR4 board with full conformal anti-corrosion coating
Front Panel: Digital speed display, function buttons, running/fault/trip LED indicators, password lock, debugging communication port.

III. Key Features

3.1 SIL3 TMR Hardware Overspeed Safety Protection

Three fully independent sampling and trip loops adopt 2-out-of-3 voting logic, which avoids false shutdown caused by single-circuit interference and ensures reliable emergency shutdown under overspeed fault, complying with strict safety standards of high-risk process industries.

3.2 Speed & Acceleration Dual-Layer Safety Protection

Real-time rotor acceleration monitoring effectively prevents runaway accidents caused by rapid load shedding and valve misoperation, forming a multi-dimensional safety defense line for turbomachinery.

3.3 Online Maintenance & Automatic Periodic Safety Test

Single-channel hot swap can be carried out under unit normal operation; built-in signal simulator realizes regular automatic protection verification, automatically records test data to meet functional safety periodic audit requirements.

3.4 Local & Remote Dual-Mode Operation & Maintenance

On-site parameter configuration and manual test are supported via front panel; Modbus communication realizes remote real-time data uploading, parameter modification and fault diagnosis, adapting to intelligent unattended power plant management mode.

3.5 Full-Cycle Fault Diagnosis & Safety Event Archiving

All abnormal working conditions and protection actions are latched with high-precision timestamps, providing authoritative historical data for post-failure accident analysis and industrial safety compliance filing.

IV. Working Principle

After power-on self-test of three independent channels, the device collects rotor pulse signals through speed sensors, converts them into precise speed values, and uploads real-time data to local display and upper monitoring system. The 2oo3 hardware voting unit judges operating conditions in real time; when two or more channels trigger the protection threshold, the relay trips instantly to activate the ETS shutdown loop and latch fault information. Single-channel faults are automatically isolated with local alarm, allowing online maintenance. The built-in signal generator regularly simulates overspeed signals to complete protection loop verification, and dual power supplies work in hot standby mode to ensure uninterrupted safety protection function.

V. Application Scenarios

Thermal & combined cycle power plants: Turbine overspeed protection and ETS safety system redundancy upgrading.
Hydropower stations: Hydraulic turbine over-speed interlock protection against water hammer runaway risks.
Petrochemical industry: SIL3 safety instrument system protection for large process compressor units.
Oil & gas pipeline stations: Unattended safety monitoring and emergency cut-off protection of compressor sets.
Legacy safety control system renovation: Upgrade single-channel protection devices to TMR triple redundant architecture to meet current functional safety compliance requirements.