SANXIN PHB-3 Portable pH Pen Meter

Overview

The SANXIN PHB-3 Portable pH Pen Meter is a compact, field-deployable electrochemical instrument engineered for rapid, reliable pH measurement in non-critical or routine monitoring applications. Based on potentiometric principle, it employs a glass pH-sensitive electrode and integrated reference system to generate a millivolt signal proportional to hydrogen ion activity in aqueous solutions. The device operates without temperature compensation—making it suitable for ambient-temperature measurements where thermal drift is minimal and process consistency is maintained. Designed as an entry-level pen-style meter, the PHB-3 delivers calibrated accuracy of ±0.01 pH against NIST-traceable USA-type buffer standards (pH 4.01, 7.00, 10.01), with a resolution of 0.1 pH across the full 0.0–14.0 pH range. Its lightweight (95 g), ergonomic form factor and IP57-rated enclosure enable safe use in humid laboratories, educational settings, aquaculture tanks, hydroponic systems, and light industrial rinse stations—where ruggedness and portability outweigh the need for advanced data logging or multi-point calibration.

Key Features

• Single-point automatic calibration at pH 7.00 using standardized USA-type buffer solutions—ensuring traceable alignment with internationally recognized reference materials
• IP57 ingress protection rating: fully dust-resistant and capable of withstanding immersion in water up to 1 m depth for 30 minutes—ideal for wet-bench environments and outdoor sampling
• Low-battery indicator and auto-power-off after 10 minutes of inactivity—extending battery life beyond 100 hours on two standard AAA cells
• Modular electrode design: compatible with replaceable 201-G plastic-body pH composite electrodes featuring proprietary connector geometry—reducing long-term ownership cost and enabling field maintenance
• High-contrast LCD display with large digits and intuitive icon feedback—including calibration status, battery level, and measurement mode indicators

Sample Compatibility & Compliance

The PHB-3 is validated for use with aqueous samples having low to moderate ionic strength and minimal suspended solids or viscous content. It is not recommended for non-aqueous solvents, highly buffered biological matrices, or aggressive oxidizing/reducing media that may degrade the glass membrane or reference junction. While not certified for GLP/GMP-regulated production environments, its calibration protocol aligns with ASTM D1293 (Standard Test Method for pH of Water) for field and screening-level assessments. The use of USA-type calibration buffers ensures compatibility with ISO 3696 Grade 3 water specifications and supports basic QA/QC workflows in teaching labs, environmental education programs, and small-scale food/beverage preparation facilities.

Software & Data Management

The PHB-3 is a standalone, analog-output-free instrument with no embedded memory, USB interface, or Bluetooth connectivity. All measurements are displayed in real time only; no data export, timestamping, or audit trail functionality is provided. This architecture intentionally omits electronic record requirements under FDA 21 CFR Part 11 or EU Annex 11—making it appropriate for non-regulated applications where manual recording suffices. For users requiring documentation, external logbooks or spreadsheet-based tracking are recommended. Firmware updates are not supported; calibration stability is verified through periodic re-checking against fresh buffer standards per ISO/IEC 17025 guidance for measurement uncertainty management.

Applications

• Educational laboratories: Student-led pH titration exercises, buffer preparation verification, and introductory electrochemistry demonstrations
• Aquaculture and hydroponics: Routine monitoring of pond, tank, or nutrient solution pH to maintain optimal growth conditions for fish, shrimp, or leafy greens
• Food service and catering: Spot-checking of rinse water, marinade solutions, or cleaning agent residuals prior to equipment sanitization
• Small-scale brewing and fermentation: Preliminary pH assessment during wort preparation or post-fermentation stabilization
• Environmental outreach programs: Community-based water quality surveys in streams, rain barrels, or urban green infrastructure

FAQ

Does the PHB-3 support automatic temperature compensation (ATC)?

No. The PHB-3 operates without temperature compensation. Measurements should be conducted at stable ambient temperatures (15–30 °C) for optimal accuracy.
Can I calibrate the meter at pH 4.01 or 10.01?

Calibration is limited to a single point at pH 7.00. Multi-point calibration is not supported by firmware.
Is the electrode replaceable, and what type is compatible?

Yes—the 201-G plastic-body pH composite electrode is specifically designed for the PHB-3 and features a custom plug-in interface.
What buffer standards are recommended for calibration?

USA-type pH buffers (NIST-traceable, e.g., pH 4.01, 7.00, 10.01) are required for consistent performance and regulatory alignment.
How often should I recalibrate during extended use?

Recalibration is advised before each measurement session or after every 10–15 readings, especially when transitioning between sample types with differing ionic strengths.