GAI 10959-201

Product Introduction

• This rack-mounted industrial isolation module is customized for field loop instrument signal isolation and conditioning, designed to receive raw 4–20mA analog signals from two-wire industrial field transmitters and complete galvanic isolation, signal filtering and standardized signal conversion for upper DCS/PLC system access.
• The module supplies regulated isolated 24VDC loop excitation power to connected field transmitters, eliminates ground loop potential difference interference generated between field site and control cabinet grounding network.
• All conditioned standard analog signals are output as isolated 4–20mA passive analog loops toward central control system, fully complying with ISA and IEC industrial field instrumentation installation specifications for continuous 24-hour fixed cabinet installation.
• The product passes CE, UL508 industrial certification and full IEC61000 EMC anti-interference verification for process industry hazardous and conventional control cabinet deployment.

3. Model Series Information

• Parent Affiliated Series: GAI 10959 Universal Isolation Transmitter Interface Module Family
• Verified sibling derivative models within same product platform:
  • 10959-101: 2-channel isolated analog input compact variant
  • 10959-301: 4-channel isolated analog output matching module
  • 10959-401: 8-channel multi-point high-density isolated input expansion module
• All series models share consistent DIN rail installation dimensional standard and internal isolation circuit design specification.

4. Technical Specifications

4.1 Power Supply Specification

• Rated Primary Input Operating Voltage: 24VDC ±10%, nominal standard working input 24VDC industrial DC power
• Max Full-Load Total Power Consumption: 2.7W under four channels fully loaded operational status
• Internal isolated field excitation power: Independent channel-isolated 24VDC source, single channel maximum available output excitation current 32mA for standard two-wire transmitter driving.

4.2 Analog Input Specification

• Total Effective Isolated Input Channels: 4 independent galvanically isolated single-ended analog input channels
• Factory native input signal standard: Fixed 4~20mA DC current input exclusively for two-wire process transmitters
• Per-channel isolation dielectric withstand voltage: 2500VAC 50Hz 1min withstand between field side and control output side of every individual channel

4.3 Analog Output Specification

• Matching output configuration: 4-channel corresponding isolated passive 4~20mA analog output, output load permissible resistance range: 0Ω ~ 550Ω maximum per channel
• Output signal linear mapping: 1:1 fixed input-output proportional mapping without factory programmable span shift

4.4 Environmental & Physical Dimension Specification

• Certified Continuous Operating Ambient Temperature Range: -20℃ ~ +60℃
• Storage & transportation temperature range: -40℃ ~ +85℃
• Allowable working relative humidity: 5%~95%RH non-condensing ambient condition only
• Overall outer dimension: 118mm(H) × 92mm(W) × 31mm(D)
• Single unit net weight: 0.28kg
• Module main body protection grade: IP20; exposed wiring terminal region protection grade: IP00

5. Function Features

1. Per-channel independent galvanic isolation architecture thoroughly cuts off field-side and control-side ground loop stray current to eliminate measurement drift induced by grounding potential difference.
2. Built-in multi-order passive RC low-pass filter circuit for every input channel to suppress industrial 50Hz/60Hz power frequency interference and field transient signal spike noise.
3. Hardware fixed open-circuit detection for each input channel; open-loop fault leads to fixed upper-scale 22mA output at corresponding output channel for upper system fault identification.
4. Front panel single shared power indicator LED: Solid green illumination represents normal 24VDC power supply access for whole module.
5. Full passive output design needs no auxiliary power supply on upper PLC/DCS input terminal side, compatible with all mainstream brand PLC analog input cards.
6. Full hardware circuit design without embedded microcontroller or stored firmware, zero risk of program corruption or parameter data loss after long-term power outage.
7. Standard global DIN35 rail snap-on mounting structure supports rapid cabinet installation and removal without auxiliary fixed accessories.
8. Internal multi-stage transient surge absorption circuit on every input terminal to resist field cable induced lightning surge voltage impact.

6. Performance Parameters

• Full-scale measurement basic accuracy: ±0.1%FS under calibrated standard 25℃ ambient environment
• Full operating range temperature drift coefficient: ≤9ppm/℃ across complete -20℃~+60℃ working temperature span
• Single channel input common-mode noise rejection ratio: ≥128dB at industrial standard 50Hz power frequency
• Rated verified MTBF value: ≥330000 continuous working hours within specified certified operating environment
• Input-output signal conversion response time: Fixed ≤180ms full-scale step response for each independent channel
• Maximum allowable instantaneous input overvoltage impulse: 2kVAC transient surge without permanent internal component damage

7. Material Composition

1. Outer plastic housing and front panel: UL94-V0 flame retardant modified black ABS engineering plastic with anti-aging and low-temperature anti-crack formulation.
2. Main circuit PCB substrate: High-Tg FR-4 industrial glass fiber printed circuit board; entire PCB surface coated with acrylic three-proof conformal coating against moisture, sulfurization and mold corrosion.
3. Core isolation component: AEC-Q102 standard high-withstand voltage optocoupler for per-channel electrical isolation.
4. Passive electronic components: Precision metal film fixed resistors, high-temperature solid tantalum capacitors, high-frequency multilayer ceramic decoupling capacitors rated for -40℃~+125℃ operating temperature.
5. External wiring terminal base: Glass fiber reinforced PA66 flame retardant nylon terminal blocks equipped with silver-plated copper alloy spring conductive shrapnel; terminal functional marking implemented via permanent laser etching.

8. Structural Characteristics

• Double-layer compact internal layout: Front panel indication layer, middle isolation & signal conditioning PCB layer; no independent rear partition layer.
• Front panel centralized layout: Global power status LED indicator, plastic positioning buckle for DIN rail locking.
• Bottom side partitioned terminal layout: Four independent input terminal groups and four corresponding output terminal groups separated by plastic isolation ribs to prevent cross-channel short-circuit from miswiring.
• Standard DIN35 snap-type buckle fixed structure integrated on module bottom edge for rapid clamping onto standard DIN mounting rail.
• PCB separates field-side analog ground and control-side output ground with independent isolated routing to block internal circuit crosstalk interference.
• Reserved narrow natural convection air clearance between PCB inner surface and outer plastic shell for passive continuous-operation heat dissipation.

9. Working Principle

1. Field Signal Input Stage: On-site two-wire process transmitter receives isolated 24VDC excitation power from module input loop and outputs 4~20mA measured analog current signal into module corresponding input terminals; input signal passes surge suppression circuit and RC filter before entering optocoupler isolation front-end circuit.
2. Isolation Conversion Stage: Optocoupler realizes complete electrical isolation between field loop and control loop, converts input current variation into isolated internal electrical variation without direct conductive connection between two sides.
3. Signal Conditioning Stage: Post-isolation precision operational amplifier circuit completes impedance matching and linear signal trimming to restore standard proportional 4~20mA analog signal.
4. Analog Output Stage: Processed standard current signal is delivered to corresponding isolated passive output terminals and flows into upper DCS/PLC analog input acquisition card to complete remote signal collection.
5. Fault Response Stage: When input channel wiring open-circuit occurs, internal fixed pull-up circuit drives corresponding output channel to lock at 22mA full-scale value for upper control system automatic fault alarm identification.
6. Power Indication Stage: Main power supply circuit drives front panel green LED to maintain steady-on state when valid 24VDC working voltage is supplied to module main power terminal.

10. Advantage Highlights

1. Independent per-channel high-voltage isolation design eliminates ground loop measurement error, the most prominent hidden trouble for long-distance field instrument wiring in process industrial sites.
2. All-hardware analog circuit design avoids digital chip failure and firmware malfunction risks, stable performance under strong electromagnetic interference industrial environment.
3. Passive output architecture eliminates extra auxiliary power requirement for upper control equipment input side, simplifying cabinet wiring layout and reducing accessory procurement cost.
4. Compact DIN rail structure occupies minimum cabinet internal installation space and supports quick field replacement during equipment maintenance.
5. Built-in input open-circuit automatic fault marking function realizes passive fault identification without additional field detection instruments.
6. Wide -20℃~+60℃ working temperature range adapts to indoor non-air-conditioned industrial control cabinet long-term continuous running requirements.
7. Full UL and CE certification meets global process equipment safety access specifications for domestic and overseas engineering projects.

11. Applicable Industries

• Petrochemical Industry: Refinery pipeline pressure, flow, temperature transmitter signal isolation for DCS system centralized acquisition.
• Water & Wastewater Treatment Industry: Sewage plant PH, dissolved oxygen, liquid level field instrument signal isolation and transmission.
• Thermal Power Generation Industry: Boiler auxiliary water supply system and flue gas analysis instrumentation analog signal conditioning and isolation.
• Pharmaceutical Fine Chemical Industry: Synthesis workshop raw material storage tank pressure and temperature transmitter signal processing.
• Natural Gas Compression Station Industry: Compressor inlet/outlet pressure and medium temperature instrument signal isolation collection.
• Food & Beverage Production Industry: Automated batching tank level and pipeline flow transmitter remote signal transmission.
• Metallurgical Smelting Industry: Furnace cooling water system pressure and temperature field analog signal anti-interference isolation processing.

12. Installation Requirements

1. Cabinet Environment Precondition: Install module inside closed ventilated industrial control cabinet; surrounding ambient temperature must remain within -20℃~+60℃, prohibit installation adjacent to high-heat components such as power transformers and power braking resistors.
2. Mechanical Mounting Specification: Snap module bottom buckle onto standard DIN35 mounting rail, confirm full clamping lock; reserve minimum 12mm vertical gap between adjacent modules for heat dissipation airflow circulation.
3. Field Input Wiring Standard: Field two-wire transmitter input cable adopts shielded twisted pair copper wire with conductor cross-section ≥0.5mm²; shielding layer single-point grounding only at cabinet terminal side, field instrument end shielding kept floating open circuit.
4. Output Wiring Specification: Control side output cable uses copper insulated wire with cross-section ≥0.5mm², separate routing away from high-current power cables to avoid electromagnetic induction interference.
5. Hazardous Area Installation Rule: For Zone2 hazardous classified cabinet installation, all external field instrument wiring must pass certified explosion-proof junction box before connecting module input terminals; direct installation within Zone0/Zone1 hazardous explosive environment is prohibited.

13. Use Precautions

1. Pre-power-on Inspection Regulation: Confirm main power terminal access voltage strictly falls within 24VDC±10% rated range before power-on; forbid direct access of AC220V mains voltage into power input terminal to avoid instant internal circuit burnout.
2. Wiring Specification Regulation: Complete all input and output wiring under full power-off module state; powered live plugging of field wiring terminals is permanently prohibited.
3. Calibration Execution Condition: Complete full four-channel accuracy calibration under stable 25℃±2℃ ambient temperature; calibration work under extreme high/low temperature environment is forbidden to guarantee conversion precision.
4. Maintenance Operation Rule: Cut off module main 24VDC input power supply entirely before detaching module from DIN rail for maintenance or replacement.
5. Spare Module Storage Standard: Uninstalled spare modules are stored inside constant-temperature dry warehouse with ambient humidity below 95% non-condensing; long-term storage in high damp, corrosive gas and salt fog environment is prohibited.
6. Internal Modification Restriction: Prohibit disassembly of sealed internal circuit components and arbitrary replacement of non-original spare parts; unauthorized circuit modification voids official product certification and warranty validity.
7. Daily Cleaning Specification: Only dry anti-static lint-free cloth can wipe front panel and terminal surface dust; direct contact of PCB and internal components with liquid cleaning solvent is forbidden.
8. Load Limitation Ban: Forbid upper-side output load resistance exceeding rated maximum 550Ω per channel; over-limit load causes output signal attenuation and measurement accuracy degradation.