YOKOGAWA GX90XA-10-LIN-3C

YOKOGAWA GX90XA-10-LIN-3C.

Overview

The GX90XA series represents Yokogawa’s precision analog input module solution designed for the SMARTDAC+ data acquisition ecosystem. Within this series, the GX90XA-10-LIN-3C is a specific configuration tailored for applications requiring low-withstand voltage DC voltage, thermocouple, and contact input measurements.

This module integrates seamlessly with Yokogawa GX10, GX20, GP10, GP20 paperless recorders, and the GM10 modular data acquisition system. It supports up to 10 universal input channels capable of handling diverse industrial signals, including DC voltage, DC current (with external shunt resistor), thermocouple (TC), RTD (resistance temperature detector), and ON/OFF contact input. The module adopts a scanner-type architecture with channel-to-channel isolation, ensuring measurement integrity even in electrically noisy environments.

As a key component of the SMARTDAC+ product line, the module inherits the series’ core strengths: expandable modular I/O architecture, high-speed measurement capabilities, real-time remote monitoring, touch-screen operation, and secure data storage options. With its compact form factor and plug-and-lock module design, the device can be easily installed, removed, and replaced without complex wiring rework.

Model Number Decoding: GX90XA-10-LIN-3C

Understanding the model breakdown is essential for proper specification and application matching.

This specific suffix code combination selects the low-withstand voltage relay scanner architecture paired with M3 screw terminals and conformal coating protection. The LIN variant differs from the U2 universal type in that it does not include built-in RTD support or a mA input shunt resistor; external shunt resistors are required for 4-20 mA loop measurements. The conformal coating (-3C) provides an additional layer of protection against moisture, dust, and corrosive gases, making it suitable for industrial environments where condensation or chemical exposure is a concern.

Technical Specifications

Input Characteristics

Measurement Accuracy (Standard Operating Conditions)

Standard operating conditions: temperature 23 ± 2 °C, humidity 55 ± 10% RH, power supply voltage 90–132 V AC or 180–264 V AC, power frequency 50/60 Hz ± 1%, warm-up time at least 30 minutes.

Note: The measurement specifications above represent high-precision performance. Typical values upon factory shipment can be more stringent — for example, 20 mV range typical accuracy can reach ±(0.01% of rdg + 5 μV) under optimal conditions.

The A/D integration time setting is critical for noise rejection. With a 16.7 ms integration time (equivalent to 60 Hz noise rejection), the accuracy figures in the table apply. For applications requiring faster response, a 1.67 ms integration time is selectable, though accuracy degrades to approximately double the values above for most ranges. This trade-off enables the module to adapt to both power-line frequency environments (50 Hz/60 Hz) and high-speed transient capture scenarios.

Thermocouple (TC) Measurement Specifications

Contact Input Specifications

General Specifications

Compliance and Safety Standards

Key Functional Features

Input Filtering and Signal Conditioning

The module incorporates sophisticated signal processing capabilities beyond basic analog-to-digital conversion. A first-order lag input filter can be applied to reduce high-frequency noise on measurement signals. The moving average function enables smoothing of fluctuating inputs, producing stable display values for processes with cyclical variations. Calibration correction allows users to adjust measurement values with slope and offset parameters, compensating for sensor positioning errors or long-term drift in measurement loops.

Burnout Detection

For thermocouple inputs, the module supports burnout detection functionality. When a thermocouple wire breaks or becomes disconnected, the module can detect the open-circuit condition and generate an alarm. This feature is critical for unattended monitoring applications where sensor failure could lead to incorrect control actions.

Bias Function

The bias function provides a method for applying fixed offsets to measurement values. Common use cases include compensating for known probe calibration offsets, adjusting for reference junction temperature errors, or correcting for measurement chain discrepancies. Unlike calibration correction (which applies both slope and offset), bias is a simple additive constant applied after scaling.

Reference Junction Compensation

Internal reference junction compensation is provided for thermocouple inputs. The compensation accuracy is maintained at ±0.5°C under stable thermal conditions. When high precision is required, external reference junction compensation (0°C ice bath or electronic reference) can be selected via software configuration.

Input Calculation

Mathematical operations can be applied to input signals before recording or display. Supported functions include addition, subtraction, multiplication, division, scaling, square root extraction, logarithmic conversion, and engineering unit scaling. These calculations are particularly useful for deriving computed parameters — for example, converting differential pressure signals to flow rates, calculating power from voltage and current measurements, or applying sensor-specific linearization curves.

High-Speed Capability

While the LIN variant is optimized for general-purpose scanning, the GX90XA platform offers high-speed versions (GX90XA-04-H0) capable of 1 ms measurement intervals. This highlights the modular flexibility of the SMARTDAC+ platform — users can mix slow and fast modules within the same system to address varying measurement requirements across different process points. For applications that require DC voltage, thermocouple, and contact measurement at 100 ms or slower scan rates, the LIN variant provides a cost-effective solution without sacrificing core accuracy specifications.

Compatible Host Systems

The GX90XA-10-LIN-3C is compatible with the following Yokogawa products:

For GX/GP systems, each main unit supports a specific number of expansion modules. When combined with expansion units (GX60), the total input capacity can reach 450 analog channels. For GM10 systems, a single GM10-2 main unit supports up to 420 analog input channels when fully populated with modules and sub-units.

Installation Notes

When using thermocouple inputs with reference junction compensation on the GX90XA-10-LIN-3C, note that installing any of the following modules directly to the right of the analog input module may degrade reference junction compensation accuracy: GX90XA-10-C1 (mA input), GX90XA-04-H0 (high-speed AI), GX90YA (analog output), GX90WD (digital I/O), or GX90UT (PID control). Keep a minimum one-slot spacing if these modules must be used in the same system.

Typical Applications

Industrial Process Monitoring

In manufacturing environments, the module measures temperature (thermocouples), voltage signals from pressure transmitters, and discrete status signals from limit switches or proximity sensors. The scanner-type architecture provides channel-to-channel isolation, eliminating ground loops that commonly plague multi-channel temperature measurement systems.

Equipment Condition Monitoring

Rotating machinery monitoring applications benefit from the module’s capability to measure vibration sensor outputs (DC voltage from IEPE accelerometers after signal conditioning), thermocouple inputs for bearing temperature, and contact closures for machine state indication. All channels are scanned at user-selectable intervals from 100 ms to 5 s, enabling trend analysis of equipment health without requiring separate dedicated monitoring systems.

HVAC and Building Automation

The module accepts 0–10 V DC signals from pressure sensors, temperature transmitters, and position feedback devices. Contact inputs can monitor filter status, fan operation, or damper feedback. With internal math functions, raw sensor voltages can be converted directly to engineering units such as °C, Pa, or m³/s before logging.

Laboratory and Test Stand Data Acquisition

For R&D and quality assurance laboratories, the GP10 or GP20 portable recorders paired with the GX90XA-10-LIN-3C create a battery-powered data acquisition solution. The conformal coating (-3C) provides protection against incidental liquid contact common in wet-lab environments. Input ranges from 20 mV to 50 V accommodate everything from thermocouple temperature measurement to strain gauge bridge outputs.

Electric Vehicle Battery Pack Testing

Although the high-voltage GX90XA-10-V1 variant is specifically designed for EV battery testing (600 V common mode withstand voltage, 100 ms measurement interval), the LIN variant can be deployed in lower-voltage auxiliary measurement roles such as coolant temperature monitoring or contactor state detection. The 600 V DC common mode withstand rating still applies, ensuring safe operation in floating measurement configurations common in battery pack test setups.

Pharmaceutical and Biotechnology

For FDA-regulated environments, the SMARTDAC+ platform supports 21 CFR Part 11 compliance options, including electronic signatures, audit trails, and data encryption. The GX90XA-10-LIN-3C provides the raw measurement data that feeds into these compliant records. When combined with GA10 data logging software, automatic data backfill ensures zero data loss during network interruptions — a critical requirement in pharmaceutical manufacturing where every batch data point must be accounted for.

Model Variants for Comparison

Understanding where the GX90XA-10-LIN-3C fits within the GX90XA product family helps in selecting the correct variant for specific applications.

Environmental Ratings and Protection

The -3C suffix denotes conformal coating application on the printed circuit board assembly. Conformal coating is a thin polymeric film applied to electronic components to protect against:

Moisture and humidity-induced corrosion

Dust and particulate contamination

Salt spray exposure near coastal installations

Chemical vapors in industrial processes

Fungal growth in tropical environments

When deployed in GX/GP series enclosures (rated IP20 for front panels), the combined protection level is sufficient for most indoor industrial environments. For outdoor or wash-down applications, the module must be installed within a suitably rated enclosure meeting NEMA 4X or IP66 specifications.

Ordering Information

Recommended accessories:

External shunt resistors (for 4–20 mA measurements) — Yokogawa part number to be specified based on current range

Replacement removable terminal block — Yokogawa part number available through authorized distributors

GA10 data logging software — for PC-based data collection and analysis

GX60 expansion unit — for systems requiring more than main unit capacity