FangZhou DDS-608 Benchtop Conductivity Meter

Overview

The FangZhou DDS-608 Benchtop Conductivity Meter is a precision electrochemical instrument engineered for reliable, multi-parameter measurement of aqueous solutions in regulated laboratory environments. Based on the fundamental principle of conductometric analysis—measuring the electrical conductance of a solution between two electrodes—the DDS-608 delivers high reproducibility across seven auto-ranging conductivity spans (from 0.000–0.200 µS/cm up to 20.0–200.00 mS/cm), each with dedicated calibration points and full-scale error control within ±0.5% FS. Its dual-mode temperature compensation (ATC/MTC) operates over an extended thermal range (−9.9 to 135.0 °C), enabling accurate normalization to reference temperatures (typically 25.0 °C) using user-adjustable temperature coefficients (0.0–10.0 %/°C). The instrument simultaneously computes and displays conductivity, resistivity, total dissolved solids (TDS), salinity (in ppt), and temperature—making it suitable for water quality validation, pharmaceutical buffer verification, environmental monitoring, and industrial process control where trace-level ionic strength assessment is required.

Key Features

• 7-step automatic conductivity ranging with independent calibration per range, ensuring optimal signal-to-noise ratio across low- and high-conductivity samples
• Adjustable cell constant (DJS = 0.01, 0.1, 1.0, or 10.0 cm⁻¹) and configurable TDS conversion factor (0.2–1.00; default 0.5), supporting diverse electrode configurations and regulatory requirements
• Backlit LCD display with intuitive menu navigation, real-time status indicators, and dual time/date stamping for audit-ready data recording
• Integrated GLP-compliant data management: 4096 memory slots storing conductivity value, temperature, date, time, and calibration metadata—including electrode ID and calibration history
• Dual calibration methodology: standard solution mode (using built-in 4-point reference set: 84.0, 1413 µS/cm, 12.88, 111.8 mS/cm) and cell constant determination mode for field verification of electrode integrity
• RS232 serial interface and 0–20 mV analog output for direct connection to LIMS, SCADA systems, or external data loggers; compatible with FangZhou EC-Link software for secure data export and electronic signature support
• Robust benchtop architecture with ISO 9001-certified manufacturing, 3-year warranty on main unit, and replacement guarantee within first 6 months for functional defects

Sample Compatibility & Compliance

The DDS-608 is validated for use with standard platinum or stainless-steel conductivity cells conforming to DIN EN 27888 and ASTM D1125 guidelines. It supports routine analysis of deionized water, boiler feedwater, wastewater effluents, seawater dilutions, nutrient solutions, and pharmaceutical-grade purified water (PW/WFI). Its measurement algorithms adhere to principles outlined in USP , ISO 7888, and EPA Method 120.1 for conductivity determination. All stored data include mandatory GLP fields: operator ID (user-definable), sample ID, calibration timestamp, and sensor identification—enabling full traceability during internal audits or regulatory inspections under FDA 21 CFR Part 11 (when used with EC-Link software and appropriate access controls).

Software & Data Management

The optional FangZhou EC-Link PC software provides secure, encrypted communication via RS232, enabling remote instrument configuration, real-time data streaming, and batch export in CSV or PDF formats. It implements role-based user authentication, electronic signatures, and immutable audit trails—including record creation/modification timestamps and operator credentials. Data files are structured to meet ALCOA+ criteria (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available), facilitating compliance with GMP/GLP workflows in QC laboratories. Raw measurements retain full resolution (e.g., 0.001 µS/cm) without rounding prior to export.

Applications

• Pharmaceutical water system validation per USP and EU Annex 1 requirements
• Environmental testing of surface water, groundwater, and wastewater per ISO 17294-2 and EPA protocols
• Food & beverage quality control: monitoring rinse water conductivity in CIP systems, brine concentration in pickling tanks
• Power generation: ultrapure water monitoring in steam cycle chemistry programs
• Academic research: electrolyte characterization in battery development and corrosion studies
• Calibration laboratory support: verification of reference standards and secondary conductivity probes

FAQ

What electrode constants are supported by the DDS-608?
The instrument accepts cells with DJS values of 0.01, 0.1, 1.0, and 10.0 cm⁻¹. Users select the appropriate constant during setup or calibration to ensure correct conductivity calculation.
Does the DDS-608 comply with FDA 21 CFR Part 11?
The hardware itself meets technical prerequisites (audit trail-capable memory, unique user IDs). Full Part 11 compliance requires implementation of EC-Link software with configured electronic signatures, audit logging, and access controls.
Can the instrument measure ultra-pure water (< 0.1 µS/cm)?
Yes—using the 0.000–0.200 µS/cm range with a DJS=0.01 cm⁻¹ cell and strict contamination control (e.g., sealed flow cell, nitrogen purging), the DDS-608 achieves stable sub-µS/cm readings with documented repeatability.
How is temperature compensation applied during measurement?
The DDS-608 applies linear temperature correction using the formula: κ₂₅ = κₜ / [1 + α(T − 25)], where α is the user-defined temperature coefficient (default 2.0 %/°C) and T is measured temperature.
Is firmware upgrade supported?
Firmware updates are available through FangZhou’s authorized service centers and require RS232 connection and proprietary update utility—ensuring version control and integrity verification prior to installation.