Woodward 9905-970

Product Brief Introduction

• This unit is field-mounted remote signal acquisition module exclusively designed for Woodward MicroNet, 505/505E turbine control systems and LinkNet distributed bus network, responsible for on-site analog voltage, analog current and 100Ω platinum RTD temperature signal centralized collection and digital conversion transmission.
• The module realizes galvanic isolation between each input channel and internal main circuit, converts collected field analog physical quantity into digital data and uploads to system main controller via dedicated LinkNet industrial fieldbus protocol.
• Every finished product passes full-channel precision calibration, 72-hour continuous power aging test, high-low temperature alternating cycling test and surge withstand verification before factory delivery, complying with UL, CE and Class I Div.2 hazardous area explosion-proof certification standard.
• It supports three-wire 100Ω RTD automatic wire resistance compensation and multi-type standard industrial analog signal adaptive identification, completes channel open-circuit/short-circuit self-diagnosis and fault information upload automatically during full-time running.

3. Technical Specifications (Core parameters marked in bold)

Power Supply Specification

1. Rated working input voltage: 24VDC, continuous allowable operating fluctuation range:18VDC～32VDC
2. Typical static operating power consumption:9W; maximum full-load peak power consumption:15W
3. Internal power circuit surge withstand capability: 900VDC transient surge suppression for input power terminal, reinforced isolation withstand voltage 2000VAC/50Hz for 60s without breakdown between power loop and signal input loop.

Signal Input Specification

1. Total independent input channel quantity:6 configurable universal input channels per unit
2. Analog signal adaptive receiving range per channel: ±10VDC, 0～10VDC, 0～5VDC, 4～20mA DC four standard industrial signal formats
3. RTD measurement specification: Compatible with industry standard 100Ω Pt100 three-wire RTD sensor, built-in automatic lead wire resistance compensation algorithm for three-core wiring loop
4. Single channel input impedance for voltage signal:33kΩ fixed input impedance; current input terminal built-in 250Ω precision sampling fixed resistor
5. A/D conversion precision index: 16-bit high-resolution analog-to-digital conversion per independent channel

Communication Specification

1. Dedicated bus protocol: Exclusive Woodward LinkNet proprietary industrial fieldbus, bus physical layer based on differential shielded twisted pair wiring
2. Maximum effective bus transmission distance: 1200m when using double-core shielded twisted cable; single LinkNet bus supports cascading maximum 32 sets of different LinkNet series I/O modules
3. Onboard communication status LED for bus link fault real-time indication.

Environmental & Dimension Specification

1. Continuous rated operating ambient temperature range:-40℃～+85℃; certified long-term component storage temperature range:-45℃～+100℃
2. Working environment relative humidity:5%～95% non-condensing relative humidity; internal circuit condensation is permanently forbidden during continuous long-term operation
3. Protection grade: IP20 internal circuit protection; front terminal cover equipped optional auxiliary housing to reach IP54 protection standard
4. Overall outer dimension: 355.6mm(L)×279.4mm(W)×101.6mm(D)
5. Net single unit weight:907g
6. Standard installation specification: DIN35 top-hat standard guide rail clamping fixed installation mode

4. Functional Features

1. Six-channel universal mixed input function: Single channel free configuration for standard DC voltage, DC current or Pt100 RTD temperature measurement mode via upper computer parameter setting without hardware modification.
2. Automatic three-wire RTD lead compensation function: Built-in hardware sampling loop eliminates measurement error caused by field RTD connecting wire resistance variation, no extra external compensation component required.
3. Full-channel galvanic isolation function: Every input channel achieves independent electrical isolation from internal main control circuit and LinkNet communication bus, effectively cutting off field site strong electromagnetic interference backflow to main control system.
4. Real-time channel fault self-diagnosis function: Continuously monitor each input channel open-circuit, short-circuit, over-range abnormal state, upload fault digital code to main controller via LinkNet bus meanwhile trigger corresponding channel fault LED indicator light up.
5. Distributed bus data transmission function: After A/D digital conversion of analog signal, data is packaged according to fixed LinkNet communication frame and uploaded to host controller cyclically at fixed sampling period.
6. Nonvolatile parameter storage function: All channel configuration mode, measurement range calibration parameters are stored in onboard EEPROM chip, configuration data keeps permanently after complete module power cut-off without repeated reset.
7. Multi-status LED indication function: Front panel reserved three groups independent LED indicators including Power, Run Status, Communication Fault for real-time working state visual identification.

5. Performance Parameters

Measurement Precision Index

• RTD temperature static measurement accuracy: ≤±0.2℃ within -50℃～+200℃ full measurement range under 25℃ rated ambient temperature
• Analog voltage/current sampling steady-state precision: ≤±0.05%FS full scale of configured signal range after factory calibration
• Channel-to-channel isolation crosstalk error: ≤0.02% full range under full-load adjacent channel signal input status

Reliability Lifespan Index

• Factory certified continuous stable service life: Minimum 70000 hours uninterrupted running under clean ventilation industrial cabinet standard installation environment
• Vibration test compliance: Pass IEC60068-2-6 standard 10Hz～200Hz full frequency sweep vibration test with 5G peak acceleration without component loose and parameter drift
• Temperature cycling reliability: No measurement precision drift and functional failure after 1200 cycles of -40℃ ↔ +85℃ alternating high-low temperature aging test

Anti-interference Performance Index

• Allowable input power supply peak-to-peak ripple: ≤20% of rated 24VDC input voltage without channel sampling disorder and data distortion
• EMC compliance standard: Fully satisfy IEC61000-6-2 industrial environment electromagnetic compatibility specification, keep stable data collection near high-power contactor, frequency converter and engine ignition electromagnetic interference equipment

6. Material Composition

1. Outer Module Shell: UL94-V0 flame retardant modified PA66+glass fiber plastic housing, matte anti-aging surface spraying treatment, integrated DIN rail buckle forming at bottom casing.
2. Main Control PCB Board: FR-4 high-Tg flame retardant epoxy resin circuit board, internal copper wiring thickness 35μm, full-board coated with three-proof conformal paint for moisture, dust and corrosive gas isolation.
3. Core Conversion Chip: Industrial wide-temperature grade 16-bit dedicated A/D conversion IC + 8-bit embedded bus communication microcontroller dual-chip architecture for signal processing and bus data packaging respectively.
4. External Wiring Terminal: Glass fiber reinforced flame retardant plastic terminal base, tin-plated phosphor bronze alloy spring wiring terminals for field sensor cable fixed connection.
5. Indicator Component: High-brightness industrial grade LED lamp beads with high-temperature resistant plastic fixed base mounted on front printed panel.
6. Internal Isolation Component: High withstand voltage miniature isolation transformer for single-channel signal galvanic isolation circuit configuration.

7. Structural Characteristics

1. Front-rear split layout structure: Front panel centralized LED indication area and rear lower side full-row wiring terminal area separated by internal plastic isolation partition board, independent space for display circuit and signal input circuit respectively.
2. Bottom integrated DIN fixed buckle structure: Bottom casing integrated one-time formed DIN35 guide rail clamping buckle, no additional accessory needed for rail installation fixing.
3. Zoned terminal layout: Rear wiring terminals partitioned by printed marking, divided into power supply terminal zone, six groups of channel input terminal zone and LinkNet bus communication terminal zone with clear functional zoning.
4. Built-in natural heat dissipation structure: Multiple uniform strip heat dissipation slots on left and right side casing, rely on natural air convection passive heat dissipation without built-in cooling fan.
5. Detachable transparent terminal protection cover: Transparent PC plastic dustproof cover installed above rear wiring terminal bank for terminal anti-dust and accidental short-circuit protection, cover can be disassembled freely during wiring operation.

8. Working Principle

1. Power conversion stage: External 24VDC rated working power access onboard isolated switching power module, converted into multi-channel stable low-voltage DC power for A/D conversion circuit, microcontroller, LED drive circuit and bus communication circuit separately.
2. Signal input isolation stage: Field RTD temperature signal or analog voltage/current signal access independent channel isolation circuit to eliminate ground loop interference between field equipment and control cabinet grounding system.
3. Analog-to-digital conversion stage: Isolated analog signal is transmitted to 16-bit high-precision A/D converter, converted into digital pulse data according to fixed sampling frequency and sent to core microcontroller for operation processing.
4. Data compensation & calibration stage: Microcontroller invokes built-in RTD lead resistance compensation algorithm and factory calibration parameter, eliminates wiring resistance error and hardware inherent sampling deviation to complete accurate physical value calculation.
5. LinkNet bus communication stage: Processed effective measurement data is packaged into standard LinkNet protocol data frame, transmitted to upper-level MicroNet/505 main controller via differential bus wiring at fixed communication cycle.
6. Fault detection & feedback stage: When channel open-circuit, short-circuit or signal over-limit fault is detected by real-time sampling circuit, module locks abnormal channel data output, lights corresponding fault indicator and uploads fault code to main controller through bus channel.

9. Advantage Highlights

1. Six-channel universal configurable design realizes one module compatible with four kinds of mainstream analog signal and Pt100 temperature signal, reduces spare part model inventory quantity and on-site module replacement cost.
2. Independent per-channel galvanic isolation design thoroughly isolates field-site various ground interference, greatly improves whole control system operation stability under severe industrial electromagnetic environment.
3. Distributed LinkNet bus architecture allows module installation close to field sensor equipment, shortens expensive shielded sensor cable laying length and reduces project wiring material cost.
4. Automatic three-wire RTD lead compensation function cancels on-site manual compensation adjustment work, shortens equipment field debugging construction cycle.
5. Full-range channel self-diagnosis function rapidly locates sensor failure, wiring breakage and short-circuit fault position, drastically shortens post-operation equipment maintenance troubleshooting time.
6. Standard DIN35 rail installation mode adapts to all international standard industrial control cabinet internal layout specification, flexible for cabinet space optimization arrangement.
7. Perfect compatibility matching with full series Woodward MicroNet, 505/505E steam/gas turbine main control equipment, unified LinkNet bus system seamless networking without extra protocol conversion accessory.

10. Applicable Industries

1. Power Generation Industry: Thermal power steam turbine auxiliary parameter monitoring, gas turbine unit exhaust temperature & lubricating oil temperature collection, distributed genset pressure/temperature signal remote acquisition.
2. Oil & Gas Industry: Onshore oilfield compressor unit temperature monitoring, natural gas processing plant pipeline pressure and medium temperature field signal collection, offshore drilling platform turbine auxiliary parameter acquisition.
3. Petrochemical Industry: Refining plant reaction kettle temperature monitoring, chemical waste gas recovery gas engine operating parameter remote signal collection.
4. Marine Engineering Industry: Ocean vessel main propulsion diesel engine cylinder temperature monitoring, ship auxiliary generator set lubrication system multi-point temperature acquisition control.
5. Mining Industry: Coal mine fixed power station turbine auxiliary equipment parameter collection, open-pit mine mobile gas power unit field analog signal remote acquisition.

11. Model Series Classification

• Parent Product Line: Woodward LinkNet Full Series Distributed Remote I/O Module Family
• Same-series core derivative model classification:
  1. 9905-971: 6-channel pure digital switch input variant model without analog/RTD measurement function
  2. 9905-972: 6-channel relay discrete output module for on-site actuator switch control signal output
  3. 9905-970J: Explosion-proof enhanced customized version with Class I Div.2 hazardous area certification for oil & gas explosive environment application
• Compatible matching host controller series: Woodward MicroNet Plus System, Woodward 505/505E Digital Turbine Governor Controller full product range

12. Installation Requirements

1. DIN Rail Mount Specification: Align bottom module buckle with standard DIN35 top-hat guide rail, press module downward until full clamping fixed; reserve minimum 25mm lateral clearance between adjacent modules for internal heat dissipation air circulation.
2. Wiring Specification: Power supply wiring adopts ≥0.75mm² stranded copper cable; RTD and analog sensor signal wiring uses double-core shielded twisted cable with shielding layer single-end grounded at control cabinet earth bar; power strong-current wiring and signal weak-current wiring keep minimum 20mm separation spacing to avoid electromagnetic coupling interference.
3. Cabinet Environmental Installation Restriction: Install inside closed ventilated control cabinet, stay away from high-power contactor, frequency converter and engine starter strong electromagnetic radiation components; reserve ≥30mm free clearance space on upper and lower sides of module casing for heat dissipation.
4. Pre-power-on Inspection Rule: Complete full wiring continuity and short-circuit inspection of power terminal and each input channel terminal before initial energization; finish upper computer channel configuration parameter download after module power-on initialization.
5. Bus Wiring Specification: LinkNet communication bus adopts dedicated differential shielded cable, bus trunk line adopts hand-in-hand cascading wiring mode, forbidden star-type branch wiring layout.

13. Usage Precautions

1. Power-on Preheating Regulation: After connecting rated 24VDC working power, keep module idle energized for minimum 3 minutes preheating before formal channel parameter calibration and signal debugging to stabilize internal A/D sampling circuit measurement precision.
2. Parameter Modification Regulation: Channel input type configuration modification must be executed under host controller offline parameter setting status, one full-channel no-load signal test is required immediately after configuration completion to verify parameter validity.
3. Anti-liquid Infiltration Regulation: Prevent lubricating oil, cleaning water and corrosive chemical solvent from splashing onto rear terminal area; liquid infiltration leads to terminal short-circuit and internal circuit permanent burnout.
4. Long-term Idle Storage Specification: Remove all external wiring after dismounting for storage over 30 days, place module inside original factory sealed anti-static carton under 10℃～35℃ dry indoor environment away from corrosive volatile gas and dust accumulation.
5. Live Operation Forbidden Regulation: Strictly prohibit live plugging/unplugging of rear wiring terminal block and LinkNet bus connector; live plug operation generates instantaneous surge voltage to damage internal A/D conversion chip and communication IC.
6. Periodic Maintenance Regulation: Complete annual routine maintenance under full power-off state including fastening loose terminal screws, cleaning front panel and terminal dust with dry compressed air; damaged spare parts must be replaced exclusively with Woodward original certified accessories.