Korno MOT500-CO2 Fixed-Mount NDIR Carbon Dioxide Gas Detector

Overview

The Korno MOT500-CO2 is a fixed-mount, industrial-grade carbon dioxide (CO₂) gas detector engineered for continuous, real-time monitoring in demanding environmental and process control applications. It employs a high-stability, imported non-dispersive infrared (NDIR) optical sensor — a measurement principle grounded in Beer-Lambert law absorption spectroscopy at the characteristic 4.26 µm wavelength band — ensuring selective, interference-resistant detection of CO₂ across wide concentration ranges. Unlike electrochemical or metal-oxide semiconductor (MOS) alternatives, NDIR technology delivers inherent long-term stability, minimal zero drift, and immunity to poisoning or aging effects from ambient contaminants. The device integrates a 32-bit microcontroller platform with embedded digital signal processing, enabling adaptive baseline compensation, temperature-pressure cross-correction (via optional external probe), and self-diagnostic routines. Designed for unattended operation in HVAC systems, greenhouses, fermentation tanks, cold storage facilities, laboratories, and confined-space safety monitoring, the MOT500-CO2 meets rigorous requirements for measurement reproducibility, functional safety, and electromagnetic compatibility in industrial settings.

Key Features

• High-selectivity NDIR CO₂ sensing with factory-calibrated optical path and reference channel for drift compensation
• Configurable measurement ranges spanning 0–500 ppm up to 0–100% VOL, supporting both trace-level indoor air quality (IAQ) and high-concentration industrial process monitoring
• 2.4-inch industrial TFT color display with real-time concentration curve plotting, historical trend overlay, and intuitive menu navigation
• Full software-based zero and span calibration — no manual potentiometer adjustment required; supports automated calibration verification via built-in reference algorithm
• Dual-stage alarm logic with programmable thresholds, hysteresis, and delay timers; configurable as high/low limit or concentration band control mode
• Robust die-cast aluminum housing rated IP66 for dust-tight and water-jet resistant performance; certified explosion-proof per GB/T 3836.1–2021, GB/T 3836.2–2021, and GB/T 3836.31–2021 (CCRI24.8021X)
• Multi-protocol output architecture: isolated 4–20 mA (16-bit DAC, 1 km range), RS485 Modbus RTU (2 km), analog voltage (0–5 V / 0–10 V), and two SPDT relays (expandable to three)

Sample Compatibility & Compliance

The MOT500-CO2 operates via diffusion, flow-through, or pump-assisted sampling — enabling flexible integration into ductwork, enclosures, or open-area mounting configurations. Its NDIR sensor exhibits negligible cross-sensitivity to common atmospheric gases (e.g., CO, CH₄, SO₂, NOₓ) under standard conditions, though high humidity (>90% RH) or condensation may require optional integrated temperature/humidity compensation or pre-conditioning filters. The unit complies with Chinese national standards for explosive atmospheres (GB/T 3836 series), and its electrical design conforms to IEC 61000-4 immunity requirements for industrial environments. While not CE-marked or UL-listed out-of-the-box, the hardware architecture supports third-party certification pathways for international deployment. For regulated environments (e.g., pharmaceutical cleanrooms or food processing lines), the device can be validated per GMP Annex 15 guidelines when paired with documented calibration procedures and audit-trail-enabled data logging systems.

Software & Data Management

The detector supports local configuration via on-device keypad and display or remotely through Korno’s PC-based configuration utility (Windows-compatible). All parameter settings — including alarm thresholds, output scaling, relay logic, and communication baud rate — are stored in non-volatile memory with automatic backup and restore functionality. Optional TCP/IP, GPRS, or 433 MHz wireless modules enable secure, time-stamped data transmission to SCADA platforms, cloud dashboards, or centralized HMI systems. When interfaced with MODBUS-compatible PLCs or DCS controllers, the device provides timestamped register reads compliant with IEC 61131-3 standards. Data integrity is preserved through cyclic redundancy check (CRC) on all serial frames and configurable write-protection for critical parameters. Firmware updates are performed via USB or RS485 using signed binary packages to prevent unauthorized modification.

Applications

• Indoor Air Quality (IAQ) monitoring in office buildings, schools, hospitals, and smart homes — complying with ASHRAE 62.1 ventilation control strategies
• Controlled-environment agriculture: CO₂ enrichment management in greenhouses and vertical farms
• Fermentation process supervision in breweries, wineries, and bioreactors where CO₂ off-gas concentration correlates with metabolic activity
• Refrigeration leak detection in CO₂-based transcritical systems (R744), particularly in commercial cold storage and supermarket cascade loops
• Confined space entry safety: pre-entry verification and continuous monitoring in tunnels, silos, manholes, and fermentation vats
• Lab-scale environmental chambers and climate simulation systems requiring trace-level CO₂ feedback control

FAQ

What is the recommended calibration interval for the MOT500-CO2?
For general industrial use, annual calibration against certified NIST-traceable gas standards is advised. In high-accuracy or regulated applications, semi-annual calibration with documented uncertainty budgets is recommended.
Can the device operate in sub-zero ambient temperatures?
The standard operating range is −20 °C to +50 °C. Operation below −20 °C requires optional heated enclosure or internal temperature regulation module to prevent condensation and optical window frosting.
Is remote firmware update supported over TCP/IP or GPRS?
Yes — firmware upgrades can be initiated via the Korno Configuration Tool over Ethernet or GPRS, provided the optional communication module is installed and network access is authorized.
Does the MOT500-CO2 support Modbus TCP in addition to Modbus RTU?
Modbus TCP is available only with the optional Ethernet interface module; standard RS485 implements Modbus RTU exclusively.
How is sensor longevity ensured in high-humidity environments?
The NDIR optical cell features hydrophobic anti-fog coating and dual-chamber sealed optics. Optional integrated humidity/temperature probe enables dynamic compensation algorithms to maintain accuracy up to 95% RH non-condensing.