OHAUS AB33PH-F Benchtop pH Meter

Overview

The OHAUS AB33PH-F Benchtop pH Meter is a precision electrochemical instrument engineered for routine and quality-critical pH, oxidation-reduction potential (ORP), and temperature measurements in academic laboratories, pharmaceutical QC labs, and industrial process support environments. Built upon the AQUASEARCHER platform—the next-generation evolution of OHAUS STARTER series—the AB33PH-F implements potentiometric measurement principles based on Nernst equation response from glass electrode systems. Its design prioritizes metrological integrity through i-Steward intelligent calibration management, which monitors electrode performance drift, calculates effective calibration validity windows, and issues proactive expiration warnings—ensuring traceable, auditable, and GLP-compliant operation without manual intervention.

Key Features

• 6.5-inch capacitive touchscreen LCD with backlight and hybrid segment-dot-matrix display for simultaneous real-time visualization of pH, mV, ORP, and temperature values
• i-Steward calibration intelligence system: auto-detects calibration status, tracks electrode aging, enforces recalibration intervals, and logs calibration events with timestamps
• High-stability analog front-end with low-noise amplifier architecture, delivering ±0.01 pH accuracy and ±1 mV mV accuracy across full range
• Dual communication interfaces: RS-232 serial port (for legacy LIMS integration) and USB-B (for direct PC connection and firmware updates)
• Robust ABS housing with integrated electrode holder and ergonomic bench footprint (51 × 210 × 142 mm); net weight: 0.5 kg
• Onboard data storage for up to 1,000 measurement records with time/date stamping, exportable via USB to CSV or TXT formats
• Comprehensive environmental rating: operational within 5–40 °C ambient temperature and ≤80% non-condensing relative humidity

Sample Compatibility & Compliance

The AB33PH-F is compatible with standard BNC-input pH electrodes—including the supplied ST310 combination electrode—and supports both aqueous and semi-aqueous samples per ISO 3696 (Grade 3 water) and ASTM D1293 guidelines. It meets Chinese national standards GB/T 604–2021 for pH meter verification and aligns with international metrological practices for calibration traceability using certified reference solutions (NIST-traceable where applicable). While not FDA 21 CFR Part 11–certified out-of-the-box, its audit-ready calibration log, user-accessible event history, and immutable timestamped data storage support GMP/GLP-aligned workflows when deployed with documented SOPs.

Software & Data Management

No proprietary software installation is required for basic operation; however, optional OHAUS DataLogger Utility (v2.1+) enables advanced data review, report generation (PDF/Excel), and batch export. All stored entries include measurement value, unit, date/time, electrode ID (if entered), calibration status flag, and operator ID field (user-configurable). The device supports password-protected user levels (Operator, Supervisor, Administrator) to enforce role-based access control over calibration, data deletion, and system settings—facilitating compliance with internal QA protocols.

Applications

• Academic teaching labs: Demonstrating acid-base equilibria, buffer capacity, and titration endpoint detection
• Pharmaceutical QC: Monitoring pH of dissolution media (USP ), injectables (USP ), and cleaning validation rinse water
• Food & beverage R&D: Measuring acidity in dairy products, fermented beverages, and fruit juices per AOAC 973.41
• Environmental testing: Field-deployable bench verification of wastewater, surface water, and soil extract pH per EPA Method 9040C
• Chemical manufacturing: In-process control of reaction mixtures, catalyst slurries, and neutralization endpoints

FAQ

Does the AB33PH-F support automatic temperature compensation (ATC)?

Yes—it accepts input from the built-in temperature sensor or external ATC probe (e.g., STTEMP30) and applies NIST-referenced thermistor algorithms for real-time pH correction.
Can I use non-OHAUS electrodes with this meter?

Yes, any BNC-compatible pH, ORP, or ion-selective electrode meeting standard output impedance (<250 MΩ) and voltage range (±1999 mV) is supported.
Is calibration data exportable in a format suitable for regulatory submission?

Calibration logs and measurement records are exportable as plain-text CSV files containing all required metadata (timestamp, value, unit, operator ID, calibration status), enabling integration into validated LIMS or ELN systems.
What is the warranty and service coverage for the AB33PH-F?

OHAUS provides a 2-year limited manufacturer warranty covering parts and labor; extended calibration certification services are available through authorized OHAUS Service Centers in APAC regions.