METTLER TOLEDO FE38 Meter pH/Conductivity/Ion Meter

Overview

The METTLER TOLEDO FE38 Meter is a rigorously engineered portable electrochemical analyzer designed for reliable, field- and lab-based measurements of pH, redox potential (mV), temperature, and electrical conductivity. Built upon METTLER TOLEDO’s legacy in precision electrochemistry, the FE38 employs high-stability analog front-end circuitry and low-drift reference electrode compensation algorithms to ensure repeatable readings across diverse sample matrices—from aqueous buffers and biological fluids to industrial process streams and environmental samples. Its dual-mode temperature compensation (automatic or manual) integrates seamlessly with NTC 30 kΩ sensors and supports both standard and non-standard calibration protocols. Unlike single-function meters, the FE38 delivers true multi-parameter interoperability: simultaneous real-time display of pH/mV/conductivity/temperature enables cross-parameter correlation critical for method validation, QC release testing, and regulatory documentation.

Key Features

• True multi-parameter capability: Simultaneous measurement and display of pH, mV, conductivity, and temperature on a single interface.
• High-fidelity analog signal conditioning: Optimized input impedance (>10¹² Ω) and low-noise amplification ensure minimal electrode loading and stable endpoint detection.
• Flexible calibration architecture: Supports up to 5-point pH calibration with linear or segmented curve fitting; includes four predefined buffer sets compliant with ISO 3696, ASTM D1193, and USP .
• Robust connectivity suite: RS232 and USB interfaces enable direct data export to LIMS, ELN, or spreadsheet environments; supports GLP/GMP-compliant audit trail generation when paired with METTLER TOLEDO LabX software.
• Modular electrode compatibility: Accepts standard BNC pH electrodes, Cinch-conductivity cells, and NTC 30 kΩ temperature probes—including optional ATC probe (P/N 12997876) for dynamic thermal correction in viscous or heterogeneous media.
• Dedicated endpoint logic: Visual (icon) and audible endpoint indication ensures operator-independent determination of stable readings—essential for unattended field deployments or training-limited environments.

Sample Compatibility & Compliance

The FE38 Meter accommodates a broad spectrum of sample types without hardware modification: aqueous standards, TRIS buffers, dairy emulsions, wastewater effluents, crude oil/water mixtures, and micro-volume samples in PCR tubes or centrifuge vials (when used with micro-electrodes such as LE422). All measurements adhere to internationally recognized metrological frameworks: pH accuracy meets ISO 7027-1:2016 traceability requirements; conductivity measurements align with ISO 7888:2019 principles for two- or four-electrode cell configurations; temperature compensation conforms to IEC 60751 Class B tolerances. The instrument’s firmware architecture supports 21 CFR Part 11–compliant user authentication and electronic signature workflows when integrated with validated LabX modules—making it suitable for regulated pharmaceutical, food safety, and environmental testing laboratories operating under GxP conditions.

Software & Data Management

Raw measurement data—including timestamp, electrode ID, calibration history, ambient temperature, and user-defined sample IDs—are stored locally in non-volatile memory (200-entry capacity) with full metadata retention. USB and RS232 outputs support ASCII-formatted exports compatible with CSV, Excel, and laboratory information management systems (LIMS). For advanced compliance, the FE38 pairs with METTLER TOLEDO LabX Lite or full LabX software to enable automated report generation, statistical process control (SPC) charting, and electronic audit trails with immutable timestamps and role-based access control. All calibration events—including buffer lot numbers, expiration dates, and deviation logs—are archived per FDA guidance on analytical instrument qualification (AIQ) and Annex 11 expectations.

Applications

• Environmental monitoring: Field-deployed pH and conductivity profiling of surface water, groundwater, and wastewater treatment influents/effluents.
• Pharmaceutical QC: Release testing of parenteral solutions, buffer preparation verification, and cleaning validation rinse water analysis per USP .
• Food & beverage: Acid-base titration endpoint confirmation, fermentation broth monitoring, and dairy product stability assessment.
• Academic research: Teaching labs requiring robust, entry-level electrochemical instrumentation with standardized calibration and reproducible output.
• Industrial process support: In-line verification of rinse cycles, chemical dosing accuracy, and bioreactor media conditioning.

FAQ

Does the FE38 Meter support conductivity measurement out-of-the-box?
Yes—the FE38 includes built-in conductivity functionality with automatic cell constant recognition when paired with METTLER TOLEDO conductivity cells (e.g., InLab® 731-ISM or LF92). No firmware upgrade or hardware add-on is required.
Can the FE38 store calibration data for multiple electrodes?
Yes—each calibration event is tagged with electrode identification (if ISM-enabled) and retained independently. Up to four distinct electrode profiles can be managed via LabX software synchronization.
Is the FE38 compliant with GLP documentation requirements?
When operated with LabX software and configured with user authentication, electronic signatures, and audit trail logging, the system satisfies core GLP principles outlined in OECD Principles of Good Laboratory Practice and EU Directive 2004/10/EC.
What temperature probe options are available for enhanced accuracy?
The optional ATC temperature probe (P/N 12997876) provides real-time thermal compensation with ±0.1 °C accuracy and is recommended for measurements in non-aqueous solvents, suspensions, or samples with high thermal inertia.
How is firmware updated on the FE38 Meter?
Firmware updates are performed via USB using METTLER TOLEDO’s official update utility; all versions are digitally signed and validated to maintain regulatory integrity and measurement traceability.