ChemTron CON90 Portable Conductivity Meter
| Brand | ChemTron |
|---|---|
| Origin | Germany |
| Model | CON90 |
| Portability | Portable |
| Conductivity Range | 0–19.99 mS/cm |
| Salinity Range | 0–100 ppt |
| Temperature Range | 0–120 °C |
| Minimum Resolution | 0.01 µS/cm / ppm |
Overview
The ChemTron CON90 Portable Conductivity Meter is a field-deployable, precision electrochemical instrument engineered for reliable measurement of electrical conductivity, total dissolved solids (TDS), salinity, and temperature in aqueous solutions. Based on four-electrode or two-electrode AC conductivity measurement principles—depending on selected cell constant—the CON90 delivers stable, reproducible readings across six decades of conductivity (0.01 µS/cm to 19.99 mS/cm), with automatic range switching and real-time temperature compensation (ATC) via integrated Pt1000 sensor. Designed for routine QC, environmental monitoring, aquaculture, boiler water testing, and educational laboratories, the CON90 complies with fundamental metrological requirements aligned with ISO 7888 (water quality — determination of electrical conductivity) and supports traceable calibration practices essential for GLP-compliant workflows.
Key Features
- Multi-parameter LCD display showing simultaneous real-time readings of conductivity, TDS, salinity, temperature, and timestamp
- Auto-hold function: automatically locks measurement when stability threshold is met (±0.5% change over 3 seconds)
- Five-point conductivity calibration capability—supports independent calibration at up to five distinct standard points within each range
- Selectable cell constants (0.1 cm⁻¹, 1.0 cm⁻¹, 10.0 cm⁻¹) to optimize sensitivity and accuracy for low-conductivity ultrapure water or high-salinity brines
- Adjustable TDS conversion factor (0.40–1.00) to accommodate varying ionic composition and improve accuracy for non-NaCl matrices
- Internal data logger stores up to 99 measurement records with date/time stamp; exportable via USB interface
- Integrated ATC compensation (0–100 °C) using Pt1000 thermistor embedded in the PC4021 composite electrode
- White backlit display for low-light conditions; powered by four AAA alkaline batteries (40 h typical runtime with backlight enabled)
Sample Compatibility & Compliance
The CON90 is validated for use with liquid samples having temperatures between 0 °C and 120 °C and pH values compatible with standard platinum/304 stainless steel electrode materials (pH 2–12). It accommodates a broad spectrum of sample types—including drinking water, wastewater effluents, seawater, hydroponic nutrient solutions, pharmaceutical rinse waters, and industrial process streams. Calibration standards include NIST-traceable KCl solutions (74 µS/cm, 1413 µS/cm, and 12.88 mS/cm), enabling compliance with ASTM D1125 and USP . While not certified for FDA 21 CFR Part 11 environments out-of-the-box, audit-ready data export (CSV format) and manual calibration logs support internal validation protocols under ISO/IEC 17025 and GMP Annex 11 frameworks.
Software & Data Management
The optional AX9010U USB interface kit includes proprietary Windows-compatible software for live data streaming, graphical trend visualization, and batch export of stored measurements. All logged entries contain immutable metadata: date, time, conductivity value, TDS/salinity equivalent, temperature, cell constant used, and operator-defined ID field. Data files are saved in plain-text CSV format without proprietary encryption, ensuring long-term readability and compatibility with LIMS integration. Firmware updates are delivered via downloadable HEX files and applied through the same USB interface—no external programmer required.
Applications
- Environmental field testing: river, lake, and groundwater conductivity profiling for salinity intrusion assessment
- Pharmaceutical water systems: monitoring of purified water (PW) and water for injection (WFI) per USP conductivity limits
- Aquaculture and marine biology labs: real-time salinity tracking during larval rearing and tank system maintenance
- Food & beverage QA: verification of cleaning-in-place (CIP) rinse water conductivity to confirm detergent removal
- Academic teaching labs: hands-on instruction in solution conductivity theory, ion mobility, and temperature-dependent electrolyte behavior
- Industrial boiler and cooling tower management: detection of condensate contamination and cycle concentration control
FAQ
Does the CON90 support automatic temperature compensation below 0 °C or above 100 °C?
No—the built-in Pt1000 sensor and ATC algorithm are validated for operation between 0 °C and 100 °C. Measurements outside this range require manual temperature correction.
Can I use third-party conductivity electrodes with the CON90?
Only ChemTron-certified electrodes (e.g., PC4021, SC4021) are guaranteed to maintain specified accuracy and ATC functionality due to proprietary impedance matching and firmware calibration mapping.
Is the 99-entry memory retained after battery replacement?
Yes—data is stored in non-volatile flash memory and persists through power loss or battery change.
What is the maximum cable length supported for the PC4021 electrode?
The standard 1-meter shielded cable is optimized for noise immunity; extension beyond 1.5 m may introduce signal drift and is not recommended without active shielding verification.
How frequently should I calibrate the instrument?
Calibration frequency depends on usage intensity and regulatory context; daily calibration is advised for GLP-critical applications, while weekly calibration suffices for routine field surveys with stable reference standards.
