Leici PHSJ-3F Benchtop pH Meter

Overview

The Leici PHSJ-3F is a high-precision benchtop pH meter engineered for routine and quality-critical electrochemical measurements in academic laboratories, pharmaceutical QC environments, environmental monitoring stations, and industrial process support labs. It operates on the fundamental principle of potentiometric measurement—detecting the potential difference between a pH-sensitive glass electrode and a stable reference electrode in aqueous solution—to determine hydrogen ion activity. With an instrument classification of 0.01-level accuracy per Chinese national standard JJG 119–2018 (equivalent to ISO 7027 and ASTM D1293 compliance frameworks), the PHSJ-3F delivers reliable, repeatable pH readings across an extended operational range of −2.00 to 20.00 pH—enabling analysis of highly acidic, neutral, and strongly alkaline samples including caustic cleaning agents, battery electrolytes, and semiconductor rinse solutions.

Key Features

• High-resolution 0.01 pH resolution with dual display modes (0.01/0.1 pH and 0.1/1 mV selectable via menu)
• Intelligent endpoint detection algorithm supporting auto-read, timed-read, interval-read, and manual sampling protocols
• Comprehensive temperature compensation: automatic (via integrated ATC probe) or manual input, with dual-unit support (°C/°F)
• Multi-standard buffer recognition: automatic identification of GB, DIN, and NIST-certified calibration solutions; supports user-defined buffer groups and custom pH standards
• Robust firmware architecture with over-the-air upgrade capability for future protocol expansion and regulatory alignment
• IP54-rated enclosure ensuring resistance to dust ingress and incidental water splashes during daily lab operation
• Built-in power management: auto-shutdown, power-loss data retention, and factory reset functionality for GLP-compliant instrument maintenance

Sample Compatibility & Compliance

The PHSJ-3F is optimized for aqueous and low-viscosity non-aqueous solutions commonly encountered in chemical synthesis, wastewater testing, food safety screening, and biopharmaceutical buffer preparation. Its triple-junction pH electrode (included as standard) minimizes liquid junction potential drift and resists clogging from proteinaceous or colloidal matrices. The instrument conforms to Good Laboratory Practice (GLP) requirements through mandatory audit trail features—including timestamped calibration logs, operator ID fields (via optional software configuration), and immutable storage of raw measurement records. While not certified to FDA 21 CFR Part 11 out-of-the-box, its data export architecture (CSV via USB/RS-232) enables integration into validated LIMS or ELN systems meeting GMP/GLP traceability mandates.

Software & Data Management

Data integrity is ensured via internal storage of up to 500 complete measurement records—each containing pH/mV/temperature values, calibration history, date/time stamp, and electrode ID (if tagged). Export is supported via two physical interfaces: RS-232 enables direct connection to serial printers compliant with ESC/P or PCL protocols, offering configurable print layouts (single-value, full record, or calibration report); USB interface connects to Windows-based PCs using Leici’s proprietary communication software, enabling bidirectional data synchronization, batch export to Excel-compatible CSV files, and remote firmware updates. All exported datasets retain native metadata structure required for regulatory review or method validation documentation.

Applications

• Quality control of buffer solutions in cell culture media preparation (USP & EP monographs)
• pH monitoring during titration endpoint verification in analytical chemistry teaching labs
• Environmental field lab analysis of surface water, soil leachates, and effluent streams per EPA Method 150.1
• Stability testing of topical pharmaceutical formulations under ICH Q5C guidelines
• In-process control of acid/base addition in fine chemical synthesis reactors
• Calibration verification of inline pH sensors used in bioreactor process analytical technology (PAT) workflows

FAQ

Does the PHSJ-3F comply with international calibration standards such as NIST or DIN?
Yes—the instrument automatically recognizes and applies correction factors for NIST-traceable, DIN-compliant, and Chinese GB-standard pH buffers. Users may also define custom buffer sets with certified values.
Can the device store calibration history alongside measurement data?
Yes—each stored dataset includes associated calibration parameters (date, buffer IDs, slope, offset, and asymmetry potential), enabling full traceability per GLP Annex 11 principles.
Is the included electrode suitable for non-aqueous or high-salt applications?
The supplied tri-junction composite electrode is optimized for general-purpose aqueous use. For ethanol/water mixtures, high-ionic-strength brines, or viscous samples, optional specialized electrodes (e.g., low-resistance Ag/AgCl reference, gel-filled body) are available separately.
What power backup mechanisms prevent data loss during unexpected shutdown?
The unit incorporates EEPROM-based non-volatile memory and capacitor-assisted write protection, preserving all calibration and measurement records even during abrupt AC power interruption.
Is USB communication compatible with modern operating systems?
Yes—Leici’s official Windows-compatible driver and desktop application support Windows 10/11 (64-bit); macOS and Linux users may access exported CSV files directly without proprietary software.