Leici PHS-3E Benchtop pH Meter
| Brand | Leici |
|---|---|
| Origin | Shanghai, China |
| Manufacturer Type | Direct Manufacturer |
| Product Origin | Domestic (China) |
| Model | PHS-3E |
| Price Range | USD 280–420 |
| Instrument Type | Benchtop |
| Parameter Types | Multi-parameter (pH, mV, Temperature) |
| pH Accuracy | ±0.01 pH |
| pH Measurement Range | −2.00 to +18.00 pH |
| pH Resolution | 0.01 pH |
| mV Range | −1999 to +1999 mV |
| mV Resolution | 1 mV |
| mV Accuracy | ±0.1% FS |
| Temperature Range | −5.0 to 110.0 °C |
| Temperature Resolution | 0.1 °C |
| Temperature Accuracy | ±0.2 °C |
| Calibration Standards | GB Standard Buffers at pH 4.00, 6.86, and 9.18 |
| Calibration Points | 1–3-point automatic buffer recognition |
| Data Storage | 50 measurement sets |
| Protection Rating | IP54 |
| Power Supply | AC 100–240 V input, DC 20 V / 1500 mA output |
| Dimensions | 242 × 195 × 68 mm |
| Weight | 0.9 kg |
Overview
The Leici PHS-3E is a precision benchtop pH meter engineered for routine laboratory and quality control applications requiring reliable electrochemical measurement of hydrogen ion activity. Based on potentiometric principle using a glass pH electrode and reference electrode (integrated in the supplied tri-combination electrode), the instrument measures the potential difference between the sensing element and reference junction, converting it into a pH value via the Nernst equation. Designed to meet ISO/IEC 17025-aligned operational expectations, the PHS-3E delivers Class 0.01 accuracy per Chinese national standard JJG 119–2018 (equivalent to IUPAC traceable calibration protocols) and supports compliance with GLP documentation workflows through structured data logging and calibration traceability.
Key Features
- High-contrast LCD display with intuitive key-based navigation and backlight-independent visibility under ambient lab lighting
- Intelligent endpoint detection algorithm enabling both equilibrium-mode (stable reading lock) and continuous monitoring mode for kinetic pH tracking
- Automatic temperature compensation (ATC) using integrated Pt1000 sensor or manual input; supports linear and non-linear compensation curves per electrode specifications
- Three-point auto-buffer recognition for GB-standard pH 4.00, 6.86, and 9.18 solutions—eliminating manual buffer entry errors and reducing calibration time by up to 40%
- IP54-rated enclosure providing dust resistance and limited water splashing protection—suitable for general wet-lab environments including QC labs, teaching facilities, and environmental testing stations
- Built-in power management: auto-shutdown after 10 minutes of inactivity; EEPROM-backed memory retains calibration coefficients and user settings during power loss
Sample Compatibility & Compliance
The PHS-3E accommodates aqueous and low-ionic-strength samples within standard pH electrode operational limits. It supports direct measurement of buffers, pharmaceutical formulations, food extracts, wastewater effluents, and educational chemistry solutions. The included tri-combination pH electrode features a low-resistance glass membrane and double-junction Ag/AgCl reference system, minimizing liquid junction potential drift in complex matrices. All calibration procedures align with GB/T 27501–2011 (equivalent to ASTM D1293 for water pH) and support audit-ready documentation for ISO 9001 and ISO/IEC 17025 accredited laboratories. Device firmware complies with electromagnetic compatibility (EMC) requirements per GB/T 18268.1–2010 (IEC 61326-1:2012).
Software & Data Management
Data handling is performed locally without proprietary software dependency. Each stored record includes timestamp, measured pH/mV/temperature values, calibration ID, electrode slope (%), and offset (mV). Users may review, export (via USB interface on optional adapter), or delete entries individually or in bulk. The 50-set memory capacity satisfies typical daily throughput for mid-volume QC labs performing batch release testing. Calibration history—including date, buffer IDs, slope, and asymmetry potential—is retained separately and accessible for internal audits or regulatory inspections (e.g., FDA 21 CFR Part 11 readiness via procedural controls, though native electronic signature functionality is not embedded).
Applications
- Pharmaceutical manufacturing: final rinse water pH verification per USP , buffer preparation validation
- Food & beverage QA: titratable acidity estimation, fermentation monitoring, shelf-life stability studies
- Environmental testing: surface water, wastewater, and soil extract analysis per EPA Method 150.1 and HJ 1147–2020
- Academic instruction: undergraduate electrochemistry labs emphasizing Nernstian behavior, electrode response kinetics, and calibration uncertainty analysis
- Chemical production: catalyst slurry pH control, neutralization endpoint detection in batch reactors
FAQ
Does the PHS-3E support GLP-compliant calibration records?
Yes—each calibration event logs date/time, buffer pH values used, calculated slope, and offset. These are retained independently of measurement data and can be manually transcribed for audit trails.
Can the instrument measure ORP (redox potential) in addition to pH?
Yes—the mV mode operates across −1999 to +1999 mV with 1 mV resolution and ±0.1% full-scale accuracy, suitable for standard redox assessments using platinum or reversible hydrogen electrodes.
Is the tri-combination electrode compatible with non-aqueous solvents?
No—it is optimized for aqueous systems. For ethanol/water mixtures or organic media, a dedicated non-aqueous pH electrode with solvent-resistant junction is recommended.
What is the expected service life of the included electrode under normal lab use?
With proper storage (in 3 M KCl solution), regular cleaning, and avoidance of protein/fat fouling, typical functional lifespan is 12–18 months. Slope degradation below 95% indicates replacement need.
Does the device offer RS-232 or USB connectivity for PC integration?
The base unit lacks built-in serial or USB ports; however, third-party TTL-to-USB adapters compatible with standard UART protocols may be used for raw data streaming when configured in continuous mode.
