YSI Pro20 Dissolved Oxygen Meter (Galvanic Cell Type)
| Origin | USA |
|---|---|
| Manufacturer Type | Authorized Distributor |
| Origin Category | Imported |
| Model No. | 6050020 |
| Instrument Type | Laboratory-Grade Portable DO Meter |
| Measurement Principle | Galvanic Electrochemical Sensor (Primary Cell) |
| DO Range | 0.00–50.00 mg/L (ppm) |
| Accuracy | ±2% of reading (±6% at 200–500% saturation) |
| Repeatability | ±0.05% |
| Detection Limit | 0.00 mg/L ± 0.2 mg/L |
| Atmospheric Pressure Compensation | Built-in Barometer (375–825 mmHg, ±3 mmHg accuracy) |
| Temperature Range | –5 to +70 °C (±0.2 °C) |
| IP Rating | IP67 |
| Data Storage | 50 measurement sets |
| Power | Two C-cell batteries (≥400 h typical life) |
| Dimensions | 21.6 × 8.3 × 5.7 cm |
| Weight | 475 g |
Overview
The YSI Pro20 Dissolved Oxygen Meter is a rugged, laboratory-grade portable instrument engineered for precise, field-deployable dissolved oxygen (DO) measurements in freshwater, wastewater, aquaculture, and environmental monitoring applications. It operates on the galvanic electrochemical principle—utilizing a self-polarizing primary cell sensor that requires no external polarization voltage, enabling rapid stabilization and eliminating warm-up delays. This architecture delivers high reproducibility and long-term stability without routine maintenance or frequent recalibration. The Pro20 integrates a built-in barometric pressure sensor for real-time atmospheric compensation, ensuring accurate saturation % and mg/L calculations across varying altitudes and weather conditions. Designed to meet the operational demands of regulatory field work and academic research, it conforms to ASTM D888 and ISO 5814 standards for electrochemical DO determination and supports GLP-compliant data acquisition through traceable calibration logging.
Key Features
- Ergonomic, dual-backlit display and keypad for reliable operation under low-light or outdoor conditions
- Modular three-part architecture: independent meter body, interchangeable cables (1 m / 4 m / 10 m / 20 m / 30 m), and swappable sensors—no tools required for field replacement
- One-touch DO calibration: completes full air-saturation calibration in ≤3 seconds with automatic barometric correction
- Ultra-fast response time: reaches 95% of final value within 8 seconds using standard membrane assemblies—among the shortest T95 values documented for handheld galvanic DO meters
- IP67-rated enclosure with dual-sealed battery compartment: instrument remains fully functional even if water enters the battery chamber
- MIL-spec waterproof connector system rated for ≥300,000 mating cycles; stainless-steel probe guard enhances mechanical durability and submersion control
- Expandable multi-parameter capability: supports optional temperature, conductivity, TDS, and salinity measurements (salinity range: 0–70 ppt, manual or auto-compensated)
Sample Compatibility & Compliance
The Pro20 is validated for use with aqueous samples across diverse matrices—including potable water, surface runoff, activated sludge, estuarine systems, and recirculating aquaculture units. Its galvanic sensor (model 605202) exhibits minimal oxygen consumption during measurement, reducing diffusion-layer disturbance and preserving sample integrity. When paired with the optional self-stirring BOD probe (605780), it meets EPA Method 4500-O G requirements for biochemical oxygen demand testing. The instrument carries CE, RoHS, and WEEE certifications, and has passed 1-meter drop testing per IEC 60068-2-32. Its design aligns with ISO/IEC 17025 documentation practices for field instruments used in accredited environmental laboratories.
Software & Data Management
While the Pro20 operates as a standalone meter with no onboard PC connectivity, its firmware is field-upgradable via USB interface using YSI’s official calibration and configuration utility. All calibrations—including date, time, barometric offset, and sensor serial tracking—are timestamped and stored internally alongside each of the 50 measurement records. Each entry includes DO (mg/L and % sat), temperature, pressure, and user-defined notes. Audit trails support GLP and GMP workflows where electronic records must demonstrate integrity, traceability, and immutability prior to export. Firmware updates maintain compliance with evolving FDA 21 CFR Part 11 expectations for electronic signatures and record retention.
Applications
- Regulatory compliance monitoring for NPDES permits and Clean Water Act reporting
- Wastewater treatment plant process control—especially aeration basin optimization and effluent verification
- Aquatic ecosystem health assessment in lakes, rivers, and wetlands
- Research-grade BOD5 analysis using the integrated stirring probe (ASTM D5210)
- Education and training labs requiring robust, intuitive instrumentation for undergraduate environmental science curricula
- Field validation of online DO analyzers and SCADA system cross-checks
FAQ
Does the Pro20 support both galvanic and polarographic DO sensors?
Yes—the instrument accepts either the galvanic sensor (605202) or polarographic sensor (605203), though only one may be connected at a time. Sensor type is auto-detected upon insertion.
Is barometric compensation mandatory for accurate DO readings?
Yes—because DO solubility is directly dependent on atmospheric pressure, the built-in barometer ensures correct conversion between % saturation and mg/L across elevation gradients and weather systems.
Can the Pro20 be used for continuous submerged deployment?
No—it is rated IP67 for temporary immersion (up to 30 minutes at 1 m depth), not for long-term submersion. For permanent installations, consider YSI’s multiparameter sondes with telemetry options.
What is the recommended calibration frequency for field use?
YSI recommends daily air-saturation calibration before first use and after significant temperature or pressure changes; zero-point calibration is not required for galvanic sensors under normal conditions.
Are calibration certificates and traceable standards available?
Yes—NIST-traceable calibration services and certified reference materials (e.g., saturated air and zero-oxygen solutions) are offered through authorized YSI service centers globally.
