LeiCi DZS-708T Multi-Parameter Water Quality Analyzer

Overview

The LeiCi DZS-708T Multi-Parameter Water Quality Analyzer is a laboratory-grade benchtop instrument engineered for high-reproducibility measurement of critical water quality parameters in environmental monitoring, municipal water treatment, food & beverage QA/QC, and academic research laboratories. It integrates three independent electrochemical measurement modules—pH/pX, conductivity, and dissolved oxygen—within a single robust architecture, enabling simultaneous or sequential analysis without hardware reconfiguration. The analyzer operates on fundamental potentiometric (pH, ion-selective electrodes, ORP), conductimetric (two-electrode AC conductivity cell), and polarographic (Clark-type membrane-covered electrode) principles. Its design adheres to international metrological standards for analytical instrumentation, including ISO 7888 (conductivity), ISO 5814 (dissolved oxygen), and IUPAC recommendations for pH calibration traceability. All measurements incorporate automatic temperature compensation (ATC) using integrated Pt1000 thermistors, and the system supports multiple reference temperatures (5.0–25.0 °C) for conductivity normalization per ASTM D1125 and ISO 7888.

Key Features

• High-resolution 7-inch color TFT touchscreen with intuitive icon-driven interface supporting English and Chinese language modes
• Triple-module architecture: simultaneous pH/pX, conductivity/resistivity/TDS/salinity/ash, and polarographic DO measurement units
• Comprehensive electrode diagnostics—including impedance monitoring, slope evaluation, and asymmetry potential assessment—for pH and ion-selective electrodes
• GLP- and GMP-compliant data management: full audit trail with user ID, timestamp, method ID, electrode serial number, calibration history, and event logs
• Flexible calibration protocols: up to 6-point pH/ion calibration; 1-point ORP; 1–5-point conductivity; zero/full-scale DO calibration with manual or auto atmospheric pressure compensation (kPa, mbar, Torr, atm)
• Advanced compensation models: non-linear conductivity compensation for natural waters; seawater salinity correction; dedicated ash content calculation per GB/T 10498 (white sugar) and GB/T 20885 (HFCS)
• IP54-rated enclosure for dust resistance and limited water ingress protection during routine lab use
• Dual connectivity: RS-232 port for direct thermal printer output (configurable report formats); USB host/device mode for PC communication via LeiCi LabLink software or U-disk-based data export

Sample Compatibility & Compliance

The DZS-708T is validated for aqueous matrices across environmental, industrial, and food-grade applications—including surface water, groundwater, wastewater effluent, boiler feedwater, pharmaceutical process water, fruit juice, syrups, and purified sugar solutions. It supports compliance with regulatory frameworks requiring documented measurement integrity: US EPA Method 150.1 (conductivity), APHA Standard Methods 4500-H⁺ B (pH), 4500-O G (DO), and 2320 B (TDS); Chinese national standards GB/T 6904 (pH), GB/T 11007 (conductivity), GB/T 5750.5 (DO), and GB/T 10498 (sugar ash). The system meets requirements for electronic record retention under FDA 21 CFR Part 11 when deployed with password-protected user roles, digital signatures, and immutable audit logs. All calibrations are traceable to NIST-certified reference materials or equivalent national metrology institute standards (e.g., DIN 19263, JIS K 0107).

Software & Data Management

Data acquisition, storage, and reporting follow strict GLP/GMP principles. Each dataset records operator ID, sample ID, electrode lot numbers, calibration status flags, environmental conditions (ambient temperature/pressure), and real-time measurement metadata. Internal memory retains 1000 complete records with searchable filters by date, parameter, or method. Export options include CSV (for LIMS integration), PDF (formatted reports with header/footer), and XML (structured audit trail). LeiCi LabLink PC software enables remote firmware updates, method template deployment, statistical analysis (mean, SD, RSD, confidence intervals), trend charting, and electronic signature-enabled report approval workflows. U-disk read/write functionality permits offline data transfer without PC dependency, while optional barcode scanner integration enables automated sample ID entry—reducing transcription errors in high-throughput labs.

Applications

• Environmental monitoring labs performing routine compliance testing per national water quality standards (e.g., China’s GB 3838, US EPA Clean Water Act)
• Drinking water utilities verifying disinfection efficacy (pH/ORP correlation), corrosion control (Langelier Index via pH/conductivity), and distribution system integrity
• Food & beverage QA/QC: ash content verification in refined sugars and high-fructose corn syrup; conductivity-based total dissolved solids screening in beverages
• Pharmaceutical water systems (PW, WFI) monitoring per USP and EP 2.2.38, including resistivity trending and TOC correlation studies
• Academic research on biogeochemical cycling—e.g., nutrient ion (NH₄⁺, NO₃⁻, F⁻) dynamics in freshwater ecosystems using GRAN plot or standard addition methods
• Wastewater treatment plants optimizing aeration basins via real-time DO saturation profiling and salinity-corrected conductivity for brine management

FAQ

Does the DZS-708T support FDA 21 CFR Part 11 compliance?
Yes—when configured with multi-level user authentication, electronic signatures, and enabled audit trail logging, it satisfies core Part 11 requirements for electronic records and signatures in regulated environments.
What electrode constants are recommended for low-conductivity samples?
For samples below 20 μS/cm (e.g., ultrapure water), a 0.1 cm⁻¹ or 0.01 cm⁻¹ conductivity cell is required; the built-in 1.0 cm⁻¹ cell is optimized for mid-to-high range measurements (100 μS/cm–2000 mS/cm).
Can custom ion calibration curves be stored and recalled?
Yes—the instrument allows creation and naming of user-defined ion methods, including custom calibration tables, concentration units (mol/L, ppm, μg/L), and measurement algorithms (direct reading, standard addition, Gran plot).
Is automatic atmospheric pressure compensation available for dissolved oxygen?
Yes—integrated barometric pressure sensing enables real-time DO saturation correction; manual entry is also supported with unit flexibility (kPa, mbar, Torr, atm).
How is data integrity ensured during power interruption?
The device features non-volatile memory and battery-backed clock; all active measurements and calibration events are committed to flash storage before power loss, with automatic recovery upon reboot.