Woodward 9905-969

Product Introduction

• This product is industrial ruggedized distributed analog input acquisition module belonging to Woodward proprietary LinkNet fieldbus system, specially customized for gas turbine, steam turbine, generator set and heavy-duty engine control system field signal collection.
• The module serves as independent remote I/O node, receives field sensor analog signals, completes on-site analog-to-digital conversion near signal source, then transmits packaged digital process data to Woodward main control unit via exclusive LinkNet bus protocol.
• Built-in onboard LCD display and physical operation keypad realize local parameter setting, real-time channel data check and fault diagnosis without extra upper computer configuration tool.
• The whole device passes UL, CE and IEC industrial safety certification, designed for continuous 24-hour uninterrupted fixed installation inside power plant control cabinet and harsh industrial field control box.

3. Model Series Information

• Fixed Core Model Code: 9905-969
• Affiliated Parent Series: Woodward LinkNet Distributed I/O Full Series (9905 serial product family)
• Matching derivative series products:
  • 9905-970: 6-Channel Isolated Analog Output Module of LinkNet system
  • 9905-971: 16-Channel Isolated Digital Input Module
  • 9905-972: 16-Channel Isolated Digital Relay Output Module
• All derivative models share identical LinkNet bus communication specification and rack installation dimensional standard with 9905-969.

4. Technical Specifications

4.1 Power Supply Specification

• Rated DC Operating Input Voltage: 18VDC ~ 32VDC, nominal standard working voltage 24VDC
• Maximum Rated Static Power Consumption: 3.1W under full six-channel loaded running state
• Internal isolated loop excitation power: Independent 24VDC loop power supply for field two-wire 4–20mA transmitter, single channel maximum output excitation current 30mA.

4.2 Analog Input Channel Core Specification

• Total Configurable Analog Input Channel Quantity: 6 independent galvanic-isolated single-ended input channels
• Natively supported field input signal types: Standard 4~20mA DC current signal; optional 0~5VDC / 1~5VDC voltage signal via internal parameter configuration
• Per-channel independent dielectric isolation withstand voltage: 500VAC between field input loop and internal module control circuit; 277VAC between bus communication circuit and field side
• Analog conversion core index: 16-bit Sigma-Delta high-precision ADC conversion chip for every single input channel

4.3 Communication Interface Specification

• Primary system communication bus: Woodward exclusive proprietary LinkNet serial fieldbus, dedicated for interconnection with Woodward 505/2301 series turbine main controllers
• Optional auxiliary communication terminal: Onboard RS485 physical interface, supports Modbus RTU protocol, configurable baud rate range from 2400bps up to 19200bps
• Module station address range: Locally configurable station code 1~99 via front panel keypad and LCD menu without hardware DIP switch modification.

4.4 Environmental & Physical Dimension Specification

• Certified long-term continuous operating ambient temperature range: -40℃ ~ +70℃; peak short-time tolerance temperature range: -40℃ ~ +85℃
• Storage & transportation temperature scope: -45℃ ~ +85℃; allowable operating relative humidity: 5%~95%RH non-condensing environment only
• Overall outer dimension: 203mm(D) × 127mm(W) × 25mm(H)
• Single unit net weight: 0.59kg
• Body protection grade: IP20 for module casing; exposed wiring terminal area protection grade: IP00.

5. Function Features

1. Independent per-channel hardware open-circuit, short-circuit and signal over-range automatic diagnosis function, abnormal channel fault code is uploaded to main controller synchronously via LinkNet bus once fault triggers.
2. User programmable multi-grade digital average filtering algorithm, effectively eliminates industrial power frequency 50Hz/60Hz common-mode noise and field transient signal glitch interference.
3. Onboard nonvolatile industrial EEPROM chip permanently stores channel signal type configuration, engineering range calibration coefficient and module communication address; all configuration data keeps intact after complete module power outage without repeated setup.
4. Front panel integrated 2-line × 24-character dot-matrix LCD plus 30-key independent operation keypad; realizes on-site real-time channel value browsing, address modification and full-channel calibration locally.
5. Complete multi-layer hardware protection design including input overvoltage protection, channel overcurrent cutoff protection, internal chip overtemperature shutdown protection and reverse power supply anti-burnout protection.
6. Supports full engineering scaling function for each channel; users set upper/lower physical range parameter to convert raw electrical signal directly into actual physical values like pressure, temperature, flow rate inside module.
7. Hot-plug compatible with standard LinkNet system installation rack; single module plug replacement does not interrupt normal running status of remaining modules on same LinkNet bus network.
8. Real-time cyclic data uploading per fixed bus schedule; synchronously transmit channel measured value, equipment operating state and fault alarm information to upper main control device.

6. Performance Parameters

• Full-scale measurement basic accuracy: ±0.1%FS under standard 25℃ rated calibration ambient condition
• Single channel fixed ADC sampling conversion period: 2.0ms per independent channel
• Calculated rated MTBF index: ≥320000 continuous working hours within specified -40℃~+70℃ operating temperature span
• Full range temperature drift coefficient: ≤7ppm/℃ across complete certified working temperature range
• Channel common-mode noise rejection ratio: ≥132dB at industrial standard 50Hz power frequency
• LinkNet bus transmission bit error rate: Zero bit error under IEC standard EMC anti-interference test environment.

7. Material Composition

1. Outer module casing: Cold rolled SPCC steel sheet with matte black electrostatic anti-corrosion spraying, sheet thickness 1.0mm, coating material conforms to UL94-V0 flame retardant standard.
2. Main control PCB substrate: High-Tg FR-4 industrial grade glass fiber circuit board; entire PCB surface coated with three-proof acrylic conformal coating for moisture-proof, sulfurization-proof and mildew-proof protection.
3. Core isolation and conversion components: AEC-Q102 certified high withstand voltage optocoupler for per-channel galvanic isolation, industrial wide-temperature grade 16-bit Sigma-Delta ADC chip imported from US brand.
4. Passive electronic components: Precision metal film fixed resistors, high-temperature solid tantalum capacitors, high-frequency ceramic decoupling capacitors, all components rated working temperature -40℃~+125℃.
5. External field wiring terminal base: Glass fiber reinforced PA66 flame retardant nylon terminal block with silver-plated copper spring shrapnel; terminal function marking via permanent laser engraving technology.
6. Internal storage accessory: Industrial serial EEPROM nonvolatile memory chip for parameter storage, no backup lithium battery required for data retention.

8. Structural Characteristics

• Three-layer compact split internal layout: Front panel display & keypad setting layer, middle analog signal conditioning & digital main control PCB layer, rear field signal wiring terminal layer.
• Front panel centralized layout: LCD screen, full-function operation keypad and module running status LED indicator group arranged in fixed partition area.
• Rear side partitioned terminal layout: 6-channel analog input terminal area, LinkNet bus communication terminal area, auxiliary RS485 terminal area; separated by plastic isolation ribs to prevent cross-region accidental short circuit.
• Standard DIN rail and rack dual-purpose fixed structure; two reserved installation holes on casing side for screw locking on cabinet mounting plate or standard LinkNet system rack card slot positioning.
• Independent ground partitioning PCB design: Analog signal ground and digital control ground adopt isolated routing layout to restrain signal crosstalk between power loop and weak current acquisition circuit.
• Reserved vertical natural convection air gap between internal PCB and outer metal shell for passive heat dissipation during long-time full-load continuous operation.

9. Working Principle

1. Field Signal Input Stage: On-site industrial two-wire transmitters output 4~20mA analog signal into corresponding channel terminals; signal first passes overvoltage and surge protection circuit then enters precision impedance matching signal conditioning circuit before isolation processing.
2. Analog-Digital Conversion Stage: Isolated 16-bit ADC chip converts continuous analog physical signal into discrete digital sampling value; built-in programmable digital filter removes abnormal transient interference data per pre-set filtering parameter.
3. Data Scaling & Logic Calculation Stage: Core industrial MCU reads filtered digital sampling data, invokes pre-stored channel engineering scaling coefficient inside EEPROM to convert raw digital value into actual physical engineering value; meanwhile judges channel open/short or over-range fault state.
4. Communication Data Packaging Stage: MCU packs six-channel real-time measured data, single-channel fault code and module operating status into fixed-format LinkNet bus data frame complying with Woodward proprietary communication protocol.
5. Bus Data Transmission Stage: Packaged data frame is transmitted via LinkNet fieldbus to Woodward upper turbine/generator main controller; when auxiliary RS485 function is enabled, same group data is synchronously output to external DCS/SCADA system via Modbus RTU.
6. Local Display & Fault Indication Stage: MCU drives front panel LCD to display real-time channel parameter and LED indicator to mark normal running or abnormal fault status according to internal logic judgment result.

10. Advantage Highlights

1. Distributed near-source signal digitization design drastically shortens long-distance analog field wiring length, effectively reduces external electromagnetic interference induced by long cable and improves whole control system signal stability.
2. Independent per-channel full galvanic isolation structure avoids single channel field abnormal overvoltage breakdown causing overall module or adjacent channel damage risk.
3. Integrated local display and keypad eliminates dependence on external configuration software for on-site debugging and parameter modification, greatly shortens field equipment maintenance construction period.
4. Low 3.1W rated power consumption design reduces cabinet internal heat accumulation, adapts to closed high-density control cabinet long-term continuous running requirement.
5. Dual communication design of exclusive LinkNet plus optional Modbus RS485 realizes flexible networking, matches standalone local control and centralized DCS remote monitoring two installation modes.
6. Wide -40℃~+70℃ working temperature design adapts to power plant outdoor auxiliary cabinet, marine engine cabin and high-low temperature harsh industrial environment installation requirement.
7. Full UL & CE global industrial safety certification meets power industry and international marine equipment safety access standard specification.

11. Applicable Industries

• Thermal Power Generation Industry: Steam turbine unit auxiliary system temperature, pressure, flow transmitter signal remote acquisition for Woodward 505/2301 governor control system.
• Gas Power Plant Industry: Gas turbine combustion chamber inlet/outlet parameter, fuel pipeline pressure and flow field sensor data centralized collection.
• Petrochemical Industry: Refinery waste heat generator set prime mover auxiliary instrument analog signal acquisition and upper control system data transmission.
• Marine Power Equipment Industry: Ship main diesel generator set engine temperature, lubricating oil pressure sensor signal monitoring module installation.
• Natural Gas Compression Station Industry: Compressor unit inlet/outlet pressure, medium temperature field analog signal remote collection for unit governor linkage control.
• Waste-to-Energy Power Generation Industry: Incineration waste heat turbine auxiliary instrumentation signal acquisition and DCS system docking.
• Heavy-Duty Diesel Engine Test Bench Industry: Dynamometer supporting engine cooling system, fuel system parameter real-time data collection.

12. Installation Requirements

1. Cabinet Environment Precondition: Install module inside closed industrial control cabinet; cabinet internal ambient temperature must stay within -40℃~+70℃, prohibit installation position adjacent to heating components like power transformer and braking resistance.
2. Mechanical Mounting Specification: Fix module via DIN rail clamping buckle or side mounting screw onto cabinet metal backboard; reserve minimum 20mm upper and lower gap between adjacent modules for heat dissipation air circulation.
3. Field Analog Signal Wiring Standard: All 4~20mA field sensor cable uses shielded twisted pair wire; shielding layer only single-point grounded at cabinet terminal side, field instrument side shielding end keeps suspended open circuit state.
4. Wire cross-section specification: Field analog signal wiring uses copper conductor with cross-section ≥0.5mm²; LinkNet bus and RS485 communication wiring adopts dedicated twisted pair cable with cross-section ≥0.75mm².
5. Bus Wiring Rule: LinkNet trunk bus uses daisy-chain wiring topology; install 120Ω terminal matching resistor at two extreme endpoints of total bus trunk to eliminate signal reflection distortion.
6. Hazardous Area Installation Rule: For Zone2 hazardous classified cabinet installation, all external field instrument wiring must pass certified explosion-proof junction box before accessing module input terminals; direct installation inside Zone0/Zone1 explosive hazardous area is permanently forbidden.

13. Use Precautions

1. Pre-power-on Inspection Regulation: Confirm external input DC voltage falls within 18~32VDC rated range before power supply switching-on; forbid direct access of 220VAC mains voltage into module power terminals to prevent instant internal circuit burnout.
2. Parameter Setting Specification: Complete channel signal type and station address configuration via front panel keypad; parameter modification takes effect after single module power cycle restart operation.
3. Calibration Execution Condition: Finish full-channel accuracy calibration under stable 25℃±2℃ ambient temperature; calibration operation under ultra-high/low temperature environment is prohibited to guarantee measurement precision.
4. Maintenance Operation Rule: Cut off module external DC input power supply completely before disassembly maintenance; forbid live plugging/unplugging field signal terminals and bus communication wiring during powered running state.
5. Spare Module Storage Standard: Uninstalled spare modules store inside constant-temperature dry warehouse with ambient humidity below 95% non-condensing; long-term storage in corrosive gas, salt fog and high damp closed space is prohibited.
6. Firmware Upgrade Restriction: Internal module firmware update only allows via Woodward official dedicated LinkNet configuration software; burning unknown third-party modified firmware is forbidden to avoid communication and channel function disorder.
7. Daily Cleaning Specification: Only dry anti-static lint-free cloth is permitted to wipe front panel keypad, LCD and terminal surface dust; direct contact of PCB and internal components with liquid cleaning solvent is permanently prohibited.
8. Overload Operation Ban: Forbid field two-wire transmitter drawing loop excitation current exceeding 30mA per single channel; continuous over-current load causes internal excitation power circuit permanent thermal damage.