METTLER TOLEDO FE20 FiveEasy™ Benchtop pH Meter
| Brand | METTLER TOLEDO |
|---|---|
| Origin | Switzerland |
| Instrument Type | Benchtop |
| Model | FE20 |
| pH Range | 0.00–14.00 |
| pH Resolution | 0.01 |
| Relative pH Accuracy | ±0.01 |
| mV/ORP Range | −1999 to +1999 mV |
| mV Resolution | 1 mV |
| Relative mV Accuracy | ±1 mV |
| Temperature Range | 0.0–100.0 °C |
| Temperature Resolution | 0.1 °C |
| Temperature Accuracy | ±0.5 °C |
| Calibration | Up to 3-point, with 4 pre-defined buffer sets |
| Display | LCD |
| Power Supply | External AC adapter |
Overview
The METTLER TOLEDO FE20 FiveEasy™ Benchtop pH Meter is a rigorously engineered, entry-level electrochemical instrument designed for routine pH and mV/ORP measurements in quality control, environmental monitoring, education, and industrial process support laboratories. Built upon METTLER TOLEDO’s six-decade heritage in electrode science and metrological traceability, the FE20 employs a stable potentiometric measurement principle—comparing the potential difference between a glass pH sensing electrode and a reference electrode against known buffer standards—to deliver repeatable, thermally compensated results. Its compact benchtop form factor integrates ergonomic design with robust mechanical architecture, minimizing footprint without compromising operational integrity. The instrument operates under ambient laboratory conditions (10–40 °C, <80% RH non-condensing) and complies with IEC 61010-1 safety standards for electrical equipment used in measurement, control, and laboratory applications.
Key Features
- Intuitive five-button interface enabling rapid initiation of measurement, calibration, and data review—including direct access to the most recent calibration report.
- Auto-endpoint detection algorithm that stabilizes readings based on signal drift rate, reducing operator dependency and improving inter-user reproducibility.
- Automatic buffer recognition during calibration using standard IUPAC- and NIST-traceable pH 4.01, 7.00, 9.21, and 10.01 buffers—eliminating manual buffer selection errors.
- Simultaneous real-time display of pH/mV value, temperature, endpoint status (e.g., “STABLE”), and system indicators (e.g., electrode condition, calibration due).
- Integrated temperature compensation via built-in sensor or optional external Pt1000 probe—ensuring accurate pH values across 0.0–100.0 °C with ±0.5 °C accuracy.
- Self-diagnostic functionality verifying electrode slope, offset, and asymmetry potential prior to calibration—supporting preventive maintenance and GLP-compliant documentation.
Sample Compatibility & Compliance
The FE20 is compatible with all METTLER TOLEDO LE-series combination electrodes—including the included LE438 triple-junction pH electrode—designed for high chemical resistance, low junction clogging, and fast response in aqueous, semi-aqueous, and mildly aggressive matrices (e.g., food extracts, wastewater effluents, buffer solutions). It supports measurements in accordance with ASTM D1293 (pH of water), ISO 10523 (water quality — determination of pH), and USP (pH measurement). While the FE20 itself does not include audit trail or electronic signature capabilities, its calibration logs and measurement history can be manually recorded to satisfy basic GLP documentation requirements; for regulated environments requiring 21 CFR Part 11 compliance, integration with LabX® software on a connected PC is recommended.
Software & Data Management
The FE20 operates as a standalone instrument with no onboard data storage or USB connectivity. All measurement and calibration events are retained only in volatile memory until power-off; users must manually transcribe results or employ external logging methods. For traceable, exportable, and searchable records, METTLER TOLEDO recommends pairing the FE20 with LabX Lite—a free PC-based application that captures real-time data via RS232 interface, enforces defined SOPs, auto-generates PDF reports, and maintains timestamped calibration histories. This configuration satisfies foundational data integrity expectations in ISO/IEC 17025-accredited testing laboratories where raw data archiving and reviewer sign-off are mandatory.
Applications
- Food & beverage QC: Monitoring acidity in dairy products, fruit juices, brewing wort, and fermented sauces per AOAC and Codex Alimentarius protocols.
- Environmental analysis: Field-deployable verification of surface water, groundwater, and wastewater pH prior to discharge—aligned with EPA Method 150.1 and EU Directive 2000/60/EC.
- Educational laboratories: Teaching core electrochemical concepts—including Nernst equation derivation, liquid junction potential, and temperature effects on pH—using a fully documented, serviceable platform.
- Pharmaceutical water systems: Conducting non-GMP grade checks on purified water (PW) and water for injection (WFI) distribution loops during routine surveillance.
- Chemical manufacturing: Verifying neutralization endpoints in batch titration support, catalyst slurry conditioning, and rinse water monitoring.
FAQ
Does the FE20 support automatic temperature compensation (ATC)?
Yes—the instrument accepts input from either its internal temperature sensor or an optional external Pt1000 probe, applying the Nernstian temperature correction factor in real time.
Can the FE20 store calibration data for later review?
It retains the most recent calibration parameters (slope, offset, buffer IDs) in RAM until power cycle; no persistent memory or export function is provided.
Is the LE438 electrode supplied with FE20K suitable for measuring viscous or protein-rich samples?
Yes—the triple-junction design minimizes clogging and silver ion contamination, making it appropriate for milk, cell culture media, and enzyme solutions.
What buffer sets are pre-programmed in the FE20?
Four standard sets: DIN (pH 1.68, 4.01, 6.86, 9.18), NIST (pH 4.01, 6.86, 9.18), USA (pH 4.01, 7.00, 10.01), and TECH (pH 7.00 only).
Does the FE20 meet IP rating requirements for splash resistance?
No—it carries no IP classification; operation is intended for controlled indoor laboratory environments only.
