CLEAN DO200 Portable Dissolved Oxygen Meter

Overview

The CLEAN DO200 Portable Dissolved Oxygen Meter is an engineered field instrument designed for rapid, reliable quantification of dissolved oxygen (DO) in aqueous environments using a self-powered galvanic cell electrochemical probe. Unlike polarographic sensors requiring polarization time and external voltage, the DO200’s galvanic electrode generates its own current proportional to oxygen partial pressure—enabling immediate measurement upon power-on. The device operates on the principle of oxygen diffusion through a gas-permeable membrane into an electrolyte-filled cell, where electrochemical reduction at the cathode produces a measurable current linearly correlated to DO concentration. Integrated automatic temperature compensation (ATC), user-adjustable salinity, and barometric pressure inputs ensure traceable accuracy across diverse sampling conditions—from freshwater streams and wastewater treatment basins to marine aquaculture systems and bioreactor effluents. Its compact, rugged housing meets IP67 ingress protection standards and features buoyant design for accidental submersion recovery—making it suitable for unattended deployment in challenging outdoor or industrial field settings.

Key Features

• Galvanic-type DO sensor with zero warm-up time: no polarization required, enabling instant measurement after startup
• High-contrast 65 × 40 mm backlit LCD display with dual-unit capability (mg/L and % saturation)
• IP67-rated enclosure with positive buoyancy—certified dust-tight and submersible up to 1 m for 30 minutes
• Automatic temperature compensation (0.0–50.0 °C) with optional manual offset adjustment for calibration refinement
• Configurable atmospheric pressure (600–1400 mbar) and salinity (0.0–40.0 g/L) inputs to correct for site-specific environmental variables
• HOLD function for stable reading capture in turbulent or low-access locations
• On-device diagnostics: one-button access to electrode slope, calibration status, and system configuration parameters
• Internal memory stores up to 50 measurement records with timestamp (date/time not embedded; user-managed via external log)
• Energy-efficient operation powered by two standard AAA alkaline cells, rated for >500 hours of intermittent use
• Ergonomic handheld form factor (94 × 190 × 35 mm) with non-slip grip surface for extended field operation

Sample Compatibility & Compliance

The DO200 is validated for direct immersion measurements in liquid-phase samples including raw and treated wastewater, surface water (rivers, lakes, reservoirs), seawater, brackish aquaculture ponds, fermentation broths, and process cooling water. It complies with fundamental metrological requirements outlined in ASTM D888-22 (Standard Test Methods for Dissolved Oxygen in Water) for field-deployable electrochemical DO instruments. While not certified for GLP or GMP-regulated data acquisition out-of-the-box, its stable galvanic sensor output, documented calibration traceability (via slope verification), and configurable environmental correction parameters support alignment with ISO/IEC 17025-compliant quality management systems when operated under defined SOPs. The absence of internal real-time clock or electronic audit trail precludes native FDA 21 CFR Part 11 compliance; however, exported data logs may be integrated into validated laboratory information management systems (LIMS) for regulated workflows.

Software & Data Management

The DO200 operates as a standalone instrument without proprietary software dependency. All configuration, calibration, and data review occur directly via the front-panel interface. Measurement records are stored locally in non-volatile memory and can be manually transcribed or exported via user-defined logging protocols. No Bluetooth, USB, or wireless connectivity is included—minimizing electromagnetic interference risks in electrically noisy industrial zones and eliminating firmware update dependencies. For laboratories requiring digital integration, the device’s consistent ASCII-style output format (mg/L and % sat values with associated T, P, S inputs) enables straightforward parsing into spreadsheet or LIMS platforms using generic serial-to-CSV conversion tools. Calibration history and sensor performance metrics (e.g., slope drift over time) must be maintained externally per institutional QA/QC documentation requirements.

Applications

• Wastewater treatment plant monitoring: influent/effluent DO profiling, aeration basin optimization, and nitrification/denitrification control
• Aquaculture and hatchery management: real-time pond DO surveillance to prevent hypoxia-induced mortality in finfish and shellfish operations
• Environmental field surveys: EPA Region-wide ambient water quality assessments, TMDL compliance tracking, and stormwater runoff characterization
• Drinking water distribution system integrity checks: detection of biofilm-related oxygen depletion in storage tanks and pipelines
• Bioprocess support: preliminary DO screening during upstream fermentation setup prior to inline sensor installation
• Academic and teaching laboratories: hands-on instruction in aquatic chemistry principles, sensor physics, and environmental parameter interdependence

FAQ

Does the DO200 require electrode polarization before use?
No—the galvanic cell design eliminates polarization time; measurements begin immediately after power-on.
Can the DO200 measure dissolved oxygen in seawater?
Yes, provided the user inputs the correct salinity value (0.0–40.0 g/L) to enable accurate solubility correction.
What is the recommended calibration frequency?
Calibration should be performed before each field session or daily in high-precision applications; zero-point verification in sodium sulfite solution and span-point validation in air-saturated water are standard practice.
Is the instrument suitable for continuous submerged deployment?
It is rated IP67 for temporary submersion (≤1 m, ≤30 min) but is not designed for long-term underwater mooring; use is intended for spot-checking and grab-sample analysis.
How is temperature compensation applied?
The built-in thermistor continuously measures sample temperature; compensation follows the Winkler-derived solubility model, adjusted dynamically by entered salinity and barometric pressure values.