OHAUS STARTER 3C Digital pH Meter

Overview

The OHAUS STARTER 3C Digital pH Meter is a precision electrochemical instrument engineered for reliable, repeatable pH and mV measurements in academic laboratories, quality control environments, and routine industrial testing. Based on potentiometric measurement principles, the device determines hydrogen ion activity via a glass pH electrode connected through a high-impedance BNC interface (input impedance >5 × 10¹² Ω), ensuring minimal signal loading and stable potential acquisition. Its dual-mode temperature compensation—manual or automatic using integrated NTC 3 kΩ thermistors—corrects for thermal drift across the full operational range (−5 °C to +105 °C), aligning measured potentials with standardized reference conditions per IUPAC and ASTM E70 guidelines. Designed for compliance-driven workflows, the meter supports traceable calibration protocols required under GLP and ISO/IEC 17025-accredited laboratories.

Key Features

• High-contrast white backlit LCD display with intuitive icon-based electrode status indicators and real-time parameter readouts—including pH, mV, temperature, and calibration progress
• Three-point auto-buffer recognition calibration with user-definable buffer sets (e.g., pH 4.01, 7.00, 10.01) enabling rapid setup and verification against NIST-traceable standards
• Simultaneous measurement of pH (0.00–14.00), redox potential (−1999 to +1999 mV), and temperature (−5 °C to +105 °C) with independent resolution settings: 0.01 pH unit, 1 mV, and 0.1 °C
• Robust ABS housing with compact footprint (160 × 200 × 65 mm) and lightweight design (0.65 kg) optimized for benchtop stability and portability between lab stations
• Dual power input compatibility: AC adapter (220 V / 50 Hz) and DC 9 V supply, supporting uninterrupted operation during extended testing cycles

Sample Compatibility & Compliance

The STARTER 3C accommodates standard laboratory pH electrodes with BNC connectors and NTC temperature probes, making it compatible with single-junction, double-junction, and refillable gel-filled electrodes from major OEMs. It meets essential electrical safety requirements per IEC 61010-1 for measurement equipment used in non-hazardous laboratory environments. While not rated for IP-classified ingress protection, its sealed front-panel design minimizes contamination risk during aqueous sample handling. Calibration data—including timestamped buffer assignments, slope, offset, and asymmetry potential—is retained in non-volatile memory, satisfying basic audit trail expectations for internal QC documentation. The instrument supports manual entry of calibration certificates and adheres to fundamental metrological traceability practices outlined in ISO/IEC 17025 Clause 6.4.

Software & Data Management

The STARTER 3C operates as a standalone analytical endpoint without proprietary software dependencies. All calibration history—including date/time stamps, selected buffers, calculated slope (%), and zero offset (mV)—is stored locally and accessible via on-device navigation. No USB or Bluetooth connectivity is provided; data export requires manual transcription or integration with external logging systems via analog output (if equipped with optional interface modules). For regulated environments requiring electronic records, users may pair the meter with validated third-party LIMS or ELN platforms using documented SOPs that define data integrity controls, including review-for-accuracy procedures and change management protocols aligned with FDA 21 CFR Part 11 Annex 11 principles.

Applications

• Routine pH verification in pharmaceutical water systems (Purified Water, WFI) per USP and EP 2.2.39
• Process monitoring in food & beverage production, including dairy fermentation, juice acidification, and brewing mash control
• Environmental water analysis (surface water, wastewater effluent) following EPA Method 150.1 and ISO 10523
• Academic teaching labs for fundamental electrochemistry experiments, including Nernst equation validation and buffer capacity studies
• Chemical synthesis QA/QC where precise proton activity governs reaction kinetics or catalyst performance

FAQ

Does the STARTER 3C support automatic temperature compensation with all electrode types?
Yes—when paired with an NTC 3 kΩ temperature probe (integrated into most modern combination electrodes), the meter performs automatic temperature compensation across 0 °C to 100 °C. Manual input is available if using non-thermistor-equipped electrodes.
Can calibration data be exported electronically?
No—the device stores only the most recent calibration record internally and does not feature digital communication ports. Export requires manual recording or integration via external hardware interfaces.
Is this instrument suitable for GMP-regulated manufacturing environments?
It may be deployed in GMP settings for non-critical process checks when supported by documented calibration procedures, periodic verification, and defined data handling SOPs—but lacks built-in audit trail or electronic signature capabilities required for fully compliant critical measurements.
What is the recommended recalibration frequency?
Per ISO 7870-2 and industry best practices, recalibration is advised before each batch of measurements, after electrode cleaning or replacement, and at least once per shift in continuous use scenarios.
Does the meter comply with NIST traceability requirements?
The instrument itself is not NIST-certified, but it enables traceable measurements when calibrated using NIST-traceable buffer solutions and documented procedures meeting ISO/IEC 17025 Section 6.4.3.