FangZhou PXJ-1C+ Nitrate Ion Meter

Overview

The FangZhou PXJ-1C+ Nitrate Ion Meter is a high-precision benchtop ion concentration analyzer engineered for reliable, trace-level quantification of nitrate (NO₃⁻) and other common anions and cations in aqueous environmental, municipal, and industrial water samples. Based on potentiometric measurement using ion-selective electrodes (ISEs), the instrument operates on the Nernst equation principle—transducing the logarithmic relationship between ion activity and electrode potential into calibrated concentration values (ppm, mol/L, etc.). Its dual-mode capability supports both direct ISE-based nitrate analysis and concurrent pH, mV, ORP, and temperature measurements—making it suitable for comprehensive water quality assessment in compliance with standard methods such as ASTM D3867, ISO 10304-1, and EPA Method 300.0 for anion determination. Designed for routine laboratory use, the PXJ-1C+ integrates robust analog front-end circuitry, high-input-impedance amplification (>3 × 10¹² Ω), and thermal stability across its full operating range (−20.0 to 135.0 °C), ensuring minimal drift during extended monitoring sessions.

Key Features

• Multi-parameter benchtop platform supporting nitrate, fluoride, chloride, bromide, ammonia, sodium, and 16 pre-programmed ions—with two user-definable ion channels
• High-resolution display with backlight and intuitive menu navigation; real-time clock and date stamping for all stored records
• GLP-compliant data management: 4096 measurement records with timestamp, electrode ID, calibration history, and operator ID fields
• Advanced calibration architecture: 2–9 point ion calibration with automatic standard curve fitting; up to 5-point pH calibration with auto-recognition of 18 certified buffer solutions
• Configurable resolution modes: 0.001/0.01/0.1 pH; 0.01/0.1/1 mV; variable significant digits (1–3) for ion concentration
• Integrated ATC (Automatic Temperature Compensation) with manual override; temperature sensor input accepts Pt1000 or thermistor probes
• Dual analog/digital connectivity: RS-232 and USB interfaces plus isolated 0–20 mV analog output for SCADA or PLC integration

Sample Compatibility & Compliance

The PXJ-1C+ is optimized for aqueous matrices including drinking water, surface water, wastewater effluent, agricultural runoff, and nutrient solution monitoring. It accommodates standard liquid-contact ion-selective electrodes (e.g., nitrate-selective PVC-membrane electrodes) via a universal electrode adapter supporting BNC, DIN, and mini-DIN configurations. All measurement protocols align with internationally recognized quality frameworks: data integrity meets GLP documentation requirements (audit trail, electronic signature readiness), and firmware supports time-stamped calibration logs, electrode performance tracking, and user-access-level permissions. While not FDA 21 CFR Part 11–certified out-of-the-box, the system’s structured data export (CSV/TXT) and immutable record timestamps facilitate validation under GMP or ISO/IEC 17025 environments when deployed with documented SOPs.

Software & Data Management

The included “FangZhou pH-Link” PC software enables bidirectional communication for configuration, real-time data streaming, batch calibration setup, and report generation. Raw datasets include measurement value, unit, temperature, electrode potential (mV), slope (%), offset (mV), and calibration status flags. Export formats are compatible with LIMS ingestion and statistical analysis tools (e.g., Microsoft Excel, JMP, R). The instrument’s internal memory retains full GLP metadata—no external storage required for regulatory audits. Firmware updates are delivered via USB stick or serial upload, preserving calibration constants and user preferences across revisions.

Applications

• Regulatory monitoring of nitrate levels in drinking water per WHO guidelines (≤50 mg/L NO₃⁻) and EU Directive 98/83/EC
• Wastewater treatment plant process control—tracking denitrification efficiency and influent nitrate loading
• Agricultural water testing for fertilizer leaching assessment and irrigation source qualification
• Laboratory analysis of soil extract solutions and hydroponic nutrient baths
• Educational use in analytical chemistry labs for ISE theory instruction and calibration methodology training
• Field-deployable support (with optional portable power supply) for rapid screening in environmental emergency response

FAQ

What ion-selective electrodes are compatible with the PXJ-1C+?
The meter supports standard BNC-output ISEs from major suppliers (e.g., Thermo Orion, Metrohm, Horiba) and includes built-in calibration routines for nitrate, fluoride, chloride, and 13 additional ions.
Does the instrument support automatic calibration verification?
Yes—each calibration event stores slope, offset, and R² values; users can review historical calibration performance and trigger re-calibration alerts based on configurable drift thresholds.
Can measurement data be exported directly to LIMS?
Raw ASCII-formatted data (CSV or TXT) with full metadata is exportable via USB or serial link, enabling seamless ingestion into validated LIMS platforms when paired with appropriate interface drivers.
Is temperature compensation mandatory during ion measurement?
Temperature compensation is recommended for quantitative accuracy; the instrument applies Nernstian correction automatically when an ATC probe is connected, or allows manual entry for fixed-temperature assays.
What is the warranty coverage for the PXJ-1C+?
The main unit carries a three-year limited warranty; electrode transducers and consumables are covered separately under standard distributor terms.