WOODWARD 8402-319 8402-119 microprocessor speed controller

WOODWARD 8402-319 8402-119 microprocessor speed controller

Product Overview

8402-319 Speed Control Controller

Product type: Multi mode digital governor for steam turbine with integrated servo drive function, belonging to the mid to high end model of 8402 series, with full functional characteristics of speed control, load regulation, safety protection and remote communication.

Design concept: With "redundant security+multi scenario adaptation" as the core, adopting a dual CPU redundant design (some versions), supporting automatic hot/cold start processes, and adapting to the continuous operation requirements in complex industrial environments.

Core advantages: Multi speed input channels, rich DI/DO interfaces, modular structure for easy maintenance, compatible with multiple industrial communication protocols.

2. 8402-119 speed controller

Product type: A turbine specific governor with overspeed protection function, belonging to the basic model of 8402 series, focusing on core speed regulation and safety protection, with simplified functions but outstanding stability.

Design concept: Guided by "high cost-effectiveness+core protection", simplify non essential expansion interfaces, strengthen key protection functions such as overspeed tripping and load limitation, and meet the standardized control requirements of small and medium-sized steam turbines.

Core advantages: CE certification compliance, direct power supply from 220V mains, convenient installation and debugging, suitable for cost sensitive single device control scenarios.

Specification parameters

1. General parameters (series commonality)

Technical indicators for parameter items

Working temperature range -20 ℃~+70 ℃ (industrial grade wide temperature design)

Storage temperature range -40 ℃~+85 ℃

Protection level IP20 (installed inside the control cabinet, requiring cooperation with dust-proof and moisture-proof cabinets)

Anti electromagnetic interference complies with IEC 61000-6-2 industrial electromagnetic compatibility standard

Mean Time Between Failures (MTBF) ≥ 50000 hours (industrial grade high reliability)

2. 8402-319 Exclusive Parameters

Technical indicators for parameter items

Working voltage 24V DC (supporting 18~32V DC wide voltage input, suitable for industrial DC power supply)

2 redundant speed input channels (compatible with magnetic pickups, Hall sensors, encoder signals)

DI input interface with 10 external alarm inputs and 10 external trip inputs (dry/wet contacts optional)

DO output interface with 6 relay outputs (used for valve control, alarm indication, trip signal)

Analog input/output (AI/AO) 4 channels AI (0~5V/4~20mA)+2 channels AO (4~20mA)

Communication interface Modbus RTU (RS-485), supporting remote monitoring and parameter tuning

Speed regulation accuracy ± 0.1% (steady-state accuracy at rated speed)

Response time ≤ 100ms (adjusting response speed during speed fluctuations)

Suitable for probe types such as magnetic pickup unit (MPU), photoelectric encoder, Hall sensor

3. 8402-119 Exclusive Parameters

Technical indicators for parameter items

Working voltage 220V AC (50/60Hz, supports 190-240V AC wide voltage input)

Speed input channel 1 main speed input (compatible with magnetic pickup signals)

DI input interface with 4 core protection inputs (overspeed, low oil pressure, high oil temperature, emergency stop)

DO output interface with 3 relay outputs (speed control valve control, overspeed alarm, fault tripping)

Analog input/output (AI/AO) 2 AI channels (4~20mA)+1 AO channel (4~20mA)

The communication interface can be equipped with Modbus RTU (RS-485), but the basic model does not have communication function

Speed regulation accuracy ± 0.2% (steady-state accuracy at rated speed)

Response time ≤ 150ms (adjusting response speed during speed fluctuations)

Certification standard CE certification (compliant with the EU Machinery Safety and Electromagnetic Compatibility Directive)

Performance characteristics

Core Performance Characteristics of 8402-319

Multi mode start-up control: supports automatic sequence of hot start/cold start, and can automatically adjust start-up parameters (such as warm-up time and acceleration slope) according to the duration of equipment shutdown to avoid thermal shock damage during cold start of the steam turbine.

Critical speed avoidance function: Built in three speed control logic, can preset critical speed range, automatically and quickly skip critical speed when the equipment accelerates, to prevent mechanical damage caused by resonance.

Dual speed monitoring redundancy safety: Two speed input channels compare speed data in real time. If the deviation exceeds the threshold (adjustable), an alarm or trip protection will be triggered immediately. It is suitable for power generation scenarios with extremely high safety requirements.

Rich expansion and communication capabilities: 10 alarm and 10 trip inputs can be connected to almost all safety monitoring signals of industrial equipment (such as oil pressure, oil temperature, vibration, displacement); The Modbus communication interface supports seamless integration with PLC and DCS systems, enabling remote parameter modification, operation status monitoring, and fault diagnosis.

Integrated design of servo drive: No additional servo amplifier is required, and the electro-hydraulic servo valve can be directly driven, simplifying the control system architecture and reducing equipment integration costs.

2. Core performance characteristics of 8402-119

Priority design for overspeed protection: Built in high-precision overspeed detection algorithm. When the speed exceeds 110%~120% of the rated value (adjustable), the trip protection is triggered within 0.05 seconds, cutting off fuel supply and closing the main steam valve. It is the core safety barrier for small and medium-sized steam turbines.

Strong load regulation stability: Adopting PID closed-loop control algorithm, it can automatically adjust the opening of the speed regulating valve according to load changes, maintain stable speed, and adapt to equipment with large load fluctuations such as generators and industrial pumps.

Convenience of direct power supply from mains: 220V AC direct power supply, without the need for additional DC power modules, reduces the complexity of on-site installation and commissioning, and adapts to the standardized distribution environment of small and medium-sized factories.

Simplified functions and high cost-effectiveness: Focusing on the core requirements of "speed regulation+protection", simplifying expansion interfaces, significantly reducing equipment procurement costs while meeting basic control functions, suitable for independent control scenarios of single devices.

Working principle

The WOODWARD 8402 series controllers are based on the core working logic of "speed acquisition closed-loop operation actuator drive". The main differences between the two models are reflected in signal processing and control strategies

Signal acquisition stage

8402-319: Real time speed of the equipment is collected through two redundant speed sensors, while receiving 10 DI alarm signals and 4 AI analog signals (such as oil pressure and temperature), achieving multi-dimensional data monitoring.

8402-119: By collecting speed through a single speed sensor and combining it with four core protection DI signals, only key parameters directly related to equipment safety are monitored.

Closed loop operation stage

8402-319: Dual CPUs (some versions) simultaneously perform speed deviation calculation, PID parameter adjustment, critical speed avoidance judgment, and output accurate control signals; If the deviation of the dual CPU calculation result exceeds the threshold, immediately switch to the backup CPU or trigger protection.

8402-119: Single CPU performs speed deviation calculation and PID regulation, prioritizing overspeed protection logic to ensure equipment safety in case of load fluctuations or sensor failures.

Execution driver phase

8402-319: Integrated servo drive module, directly outputs current signal to drive the electro-hydraulic servo valve, controls the steam inlet of the turbine, and achieves precise adjustment of speed and load; Simultaneously output alarm and trip signals through the DO interface.

8402-119: Output switch signal to control the actuator of the speed regulating valve and regulate the inlet steam flow; When overspeed is detected, a trip signal is directly output to the main steam valve actuator to cut off fuel supply.