FangZhou PHS-3F+ Benchtop pH Meter
| Brand | FangZhou |
|---|---|
| Origin | Sichuan, China |
| Instrument Type | Benchtop |
| Measurement Parameters | pH, mV, Rel.mV, ORP, ISE, Temperature (T) |
| pH Range | (−5.00 to 20.00) pH |
| pH Resolution | 0.01 pH / 0.1 pH (adjustable) |
| pH Accuracy | ±0.01 pH |
| pH Repeatability | 0.01 pH |
| Calibration Points | 1–5 point |
| Supported Buffer Standards | JJG 119 (China), METTLER TOLEDO (EU), Merck (Germany), DIN 19267 (Germany) — 4 groups, 20 total standard solutions |
| mV Range | (−2000.0 to +2000.0) mV |
| mV Resolution | 0.1 mV / 1 mV (adjustable) |
| mV Accuracy | ±0.1% FS or ±0.2 mV |
| Temperature Range | (−20.0 to 135.0) °C |
| Temperature Resolution | 0.1 °C |
| Temperature Accuracy | ±0.2 °C |
| Input Impedance | ≥1 × 10¹² Ω |
| Data Storage | 1000 measurement records |
| GLP Compliance | Full GLP support (sample ID, operator ID, calibration history, timestamped audit trail) |
| Interface | RS232 (dual-mode: printer output & PC data transfer) |
| Power Supply | DC 9 V, 500 mA (center-positive) |
Overview
The FangZhou PHS-3F+ is a high-precision benchtop pH meter engineered for rigorous laboratory environments where trace-level accuracy, regulatory compliance, and multi-parameter versatility are essential. Based on potentiometric measurement principles using a glass electrode and reference junction, the instrument delivers stable, reproducible readings across an extended pH range of −5.00 to 20.00 — accommodating highly acidic, neutral, and strongly alkaline samples encountered in pharmaceutical development, bioprocess monitoring, food safety testing, and environmental water analysis. Its 0.01 pH resolution and ±0.01 pH accuracy meet the performance requirements of ISO 8655, ASTM E70, and USP , making it suitable for method validation under GLP and GMP frameworks. The device employs a high-input-impedance amplifier (≥1 × 10¹² Ω) to minimize loading errors during low-conductivity measurements, such as those involving pure water or biological buffers.
Key Features
- True-color TFT LCD display with graphical interface, intuitive menu navigation, and real-time calibration curve visualization
- Intelligent operating system supporting method management, electrode lifecycle tracking, user-defined calibration protocols, and full GLP-compliant audit trails
- Multi-parameter capability: simultaneous measurement of pH, mV, relative mV, ORP, ion-selective electrode (ISE) response, and temperature
- Auto-recognition of four international buffer sets (JJG 119, METTLER TOLEDO, Merck, DIN 19267), enabling seamless one-touch calibration across up to five points
- Automatic temperature compensation (ATC) with dual-mode selection (automatic or manual); temperature range: −20.0 to 135.0 °C
- Three operational modes: real-time continuous measurement, timed interval acquisition, and auto-triggered endpoint detection
- Isopotential function for zero-potential electrode compatibility, critical for specialized reference systems
- Comprehensive self-diagnostic suite evaluating electrode slope, asymmetry potential, junction resistance, and internal circuit integrity
- Configurable data logging intervals (0–3600 s) and onboard storage for 1000 measurement records with timestamp, sample ID (10 slots), and operator ID (10 slots)
Sample Compatibility & Compliance
The PHS-3F+ supports a broad spectrum of sample matrices through interchangeable electrode configurations — including general-purpose, low-conductivity (pure water), food-grade stainless steel penetration, semi-micro, micro-volume (≥15 µL), planar surface, high-alkali, and HF-resistant electrodes. This modularity ensures metrological validity across applications ranging from USP purified water testing (Category I/II/III) to ISO 22000-certified food production lines and EPA Method 9040C wastewater characterization. The instrument fully conforms to GLP documentation standards per OECD Principles of Good Laboratory Practice, maintaining immutable records of calibration dates, buffer identities, electrode serial numbers, and operator credentials. All stored data include ISO 8601 timestamps and are exportable in CSV, Excel (.xlsx), or plain-text formats via RS232 — facilitating integration into LIMS or electronic lab notebook (ELN) platforms compliant with FDA 21 CFR Part 11.
Software & Data Management
Data transfer and archival are executed via standard RS232 serial communication, supporting two interoperable workflows: direct thermal printing (with four report templates — Simple, Standard, GLP-compliant, and Custom) and bidirectional PC synchronization. The included data acquisition software enables batch download, spectral trend plotting, statistical summary generation (mean, SD, RSD), and comparative analysis across multiple datasets. Each record preserves contextual metadata: sample ID, operator ID, electrode model and calibration status, ambient temperature, and measurement mode. Audit logs are write-protected and cannot be edited post-acquisition — satisfying ALCOA+ criteria (Attributable, Legible, Contemporaneous, Original, Accurate, Complete, Consistent, Enduring, Available) for regulated industries.
Applications
- Pharmaceutical QC/QA: pH verification of injectables, dialysis solutions, and cell culture media per USP and EP 2.2.3
- Food & Beverage: pH profiling of dairy products, fermented foods, meat extracts, and acidic beverages in accordance with AOAC 973.41 and ISO 2918
- Environmental Monitoring: Surface water, wastewater, and soil leachate analysis aligned with ISO 10523 and EPA 150.1
- Academic & Industrial Research: Kinetic studies requiring high-resolution pH tracking during titrations, enzymatic reactions, or polymerization processes
- Power & Semiconductor: Ultrapure water (UPW) monitoring in boiler feedwater and rinse baths per ASTM D1129 and SEMI F63
FAQ
Does the PHS-3F+ support FDA 21 CFR Part 11-compliant electronic signatures?
No — the instrument itself does not implement electronic signature functionality; however, its immutable, timestamped data export architecture enables downstream Part 11 compliance when integrated with validated third-party LIMS or ELN systems.
Can the meter perform automatic calibration without user intervention?
It supports automated buffer recognition and one-touch calibration initiation, but final confirmation and acceptance of calibration results require operator action to ensure procedural accountability.
What is the maximum allowable sample conductivity for accurate pH measurement?
The instrument maintains specified accuracy down to conductivities of 5 µS/cm, provided the appropriate low-conductivity electrode (e.g., FZ-600T or pure-water variant) is used and ATC is enabled.
Is firmware upgrade supported via RS232?
Yes — firmware updates can be performed using the manufacturer-provided utility software and a standard RS232-to-USB adapter.
How is electrode performance validated during routine use?
The built-in diagnostics continuously monitor electrode slope (%/pH), asymmetry potential (mV), and junction potential stability — all displayed graphically alongside pass/fail thresholds aligned with ISO 7888 and IUPAC recommendations.
