Aquaread AP-700 & AP-800 Portable Multiparameter Water Quality Analyzers

Overview

The Aquaread AP-700 and AP-800 are rugged, field-deployable multiparameter water quality analyzers engineered for high-accuracy in situ measurements across freshwater, estuarine, and marine environments. Built on a modular sensor architecture, both instruments operate on the principle of electrochemical (pH, ORP, DO), conductometric (conductivity), thermistor-based (temperature), and optical scattering (turbidity, AP-800 only) measurement techniques. The AP-700 delivers core physicochemical parameters—pH, ORP, conductivity, dissolved oxygen, and temperature—while the AP-800 extends functionality with an integrated ISO 7027-compliant turbidity sensor using 90° light scattering at 860 nm. Designed for long-term stability and repeatability, each sensor employs factory-calibrated, temperature-compensated transducers with digital signal conditioning to minimize drift and cross-sensitivity. The system is not intended for continuous unattended operation but optimized for discrete profiling, transect surveys, and regulatory grab-sample verification where portability, rapid deployment, and data traceability are critical.

Key Features

• Marine-grade anodized aluminum housing rated IP68 (sensor) and IP67 (Aquameter display unit), enabling reliable operation in rain, splash zones, and submerged conditions up to 30 m depth (AP-700/AP-800 sensors).
• Modular, hot-swappable sensor cartridges with embedded calibration memory—each probe retains its unique calibration coefficients, serial number, and firmware version.
• 3-meter reinforced polyurethane cable with strain relief and optional extension kits (up to 100 m); factory-replaceable to maintain signal integrity and waterproof integrity.
• Dual-mode power management: rechargeable Li-ion battery (≥16 h typical runtime) or external 5–24 V DC input for extended field use.
• Integrated real-time temperature compensation per parameter: NIST-traceable Pt1000 RTD for temperature; automatic linear/nonlinear EC compensation per ASTM D1125; DO saturation correction per Winkler-derived solubility models.
• Onboard data logging capacity of 100,000+ timestamped records with GPS tagging (when paired with external GNSS module via Bluetooth or USB-C).

Sample Compatibility & Compliance

The AP-700 and AP-800 are validated for direct immersion in natural waters ranging from deionized freshwater (conductivity ≥1 µS/cm) to full-strength seawater (conductivity ≤55 mS/cm). Sensor response times meet ISO 5814 (DO), ISO 7888 (conductivity), and ISO 10523 (pH) requirements under dynamic flow conditions (>0.3 m/s). Turbidity measurement on the AP-800 complies with ISO 7027 for formazin-equivalent units (FNU) across 0–1000 FNU, with built-in air bubble detection and automatic zero stabilization. All electronics conform to IEC 61326-1 (EMC) and IEC 61000-4 series immunity standards. Device firmware supports audit-ready operation per GLP and ISO/IEC 17025 laboratory requirements, including user authentication, electronic signatures, and immutable metadata embedding (date/time, operator ID, location, calibration status).

Software & Data Management

Data acquisition and post-processing are managed via AquaLink PC software (Windows/macOS), which provides full configuration control, multi-parameter trend visualization, statistical summary reporting (min/max/mean/stdev), and export to CSV, Excel, or EPA-compatible formats (e.g., .wqf, .csv for WQX ingestion). AquaLink enforces 21 CFR Part 11-compliant workflows—including role-based access control, electronic signature capture, and full audit trail of all calibration, configuration, and data export events. Raw sensor outputs are stored with embedded calibration history and environmental context (e.g., barometric pressure, salinity-derived density correction), ensuring full metrological traceability. Optional cloud synchronization enables secure, encrypted upload to Aquaread’s AquaCloud platform for team-based data review, automated QA/QC flagging, and integration with GIS mapping tools.

Applications

• Regulatory compliance monitoring (e.g., EU WFD, US Clean Water Act Section 303(d), China’s GB 3838-2002) for surface water bodies, wastewater effluents, and drinking water sources.
• Academic and governmental limnological/oceanographic research requiring high-fidelity vertical profiling, benthic boundary layer characterization, or tidal cycle sampling.
• Environmental impact assessments (EIAs) and baseline studies for infrastructure projects, including dredging, coastal development, and aquaculture siting.
• Field validation of fixed online monitoring stations—used as reference-grade mobile verification tools during sensor intercomparison campaigns.
• Educational fieldwork where durability, intuitive interface, and pedagogical data transparency support undergraduate and graduate hydrology curricula.

FAQ

What is the maximum operational depth for the AP-700 and AP-800 sensors?

Both sensors are rated IP68 and certified for continuous submersion up to 30 meters. Pressure testing is performed per IEC 60529 protocols.
Can the AP-700 be upgraded to AP-800 functionality in the field?

No—turbidity sensing requires dedicated optical hardware and firmware. AP-800 must be purchased as a complete sensor assembly.
Is AquaLink software validated for regulated environments?

Yes. AquaLink v4.2+ includes 21 CFR Part 11 modules with configurable audit trails, electronic signatures, and role-based permissions—validated for GxP-aligned laboratories.
How often do sensors require recalibration?

Typical recalibration intervals are 3–6 months under routine use; however, field verification against NIST-traceable standards before and after critical deployments is recommended per ISO/IEC 17025 Clause 7.7.
Does the system support third-party telemetry or SCADA integration?

Yes—via ASCII Modbus RTU over RS-485 (optional interface module) or ASCII output over USB-C, enabling integration with Campbell Scientific, OTT Hydromet, or Siemens Desigo platforms.