METTLER TOLEDO SevenGo Pro SG/FE/FG/EL Series Portable pH / Conductivity / Ion Concentration / Dissolved Oxygen Meters

Overview

The METTLER TOLEDO SevenGo Pro SG/FE/FG/EL series represents a modular family of portable electrochemical analyzers engineered for precision, regulatory compliance, and field-deployable robustness. Each model operates on the same core platform architecture but is optimized for distinct electrochemical measurement principles: the SG series employs high-stability glass electrode potentiometry for pH and redox potential (ORP); the FE series applies four-electrode AC conductivity measurement with automatic cell constant compensation; the FG series utilizes ion-selective electrode (ISE) potentiometry with Nernstian slope evaluation and sample matrix correction; and the EL series implements Clark-type polarographic or optical luminescence-based dissolved oxygen detection, depending on sensor configuration. All units comply with fundamental metrological requirements outlined in ISO 17025 for calibration traceability and feature built-in temperature compensation algorithms aligned with ASTM D1125 (pH), ASTM D1123 (conductivity), and ISO 5814 (dissolved oxygen). Designed for use in environmental monitoring, wastewater treatment, pharmaceutical QC, food safety labs, and academic research, the series bridges the gap between benchtop-grade accuracy and true portability—without sacrificing measurement integrity under variable ambient conditions.

Key Features

• Rugged IP67-rated enclosure with chemical-resistant polymer housing, tested per IEC 60529 for dust and immersion resistance (1 m for 30 min)
• SmartSensor™ digital interface enabling plug-and-play electrode recognition, automatic parameter loading (e.g., slope, offset, cell constant, membrane type), and firmware-matched calibration history retention
• High-resolution color TFT display (320 × 240 pixels) with adjustable backlight and intuitive icon-driven navigation supporting multilingual UI (English, German, French, Spanish, Chinese, Japanese)
• Internal rechargeable Li-ion battery providing ≥100 hours of continuous operation (pH mode) or ≥40 hours (simultaneous DO + conductivity)
• Real-time stability indicator and measurement uncertainty estimation based on signal noise, temperature drift, and electrode response time
• GLP-compliant audit trail: all calibrations, measurements, and configuration changes are timestamped, operator-ID tagged, and stored with electrode serial numbers and environmental metadata (T, P, humidity)

Sample Compatibility & Compliance

The SevenGo Pro platform accommodates aqueous samples across wide dynamic ranges: pH 0–14, conductivity 0.01 µS/cm–500 mS/cm, ion activity 10⁻⁶–10¹ mol/L (for Na⁺, K⁺, F⁻, Cl⁻, NO₃⁻, NH₄⁺, Ca²⁺, among others), and dissolved oxygen 0–20 mg/L (0–200% air saturation). Electrodes are certified to ISO 8655-5 for volumetric accuracy and validated per USP for conductivity system suitability. The entire series supports 21 CFR Part 11–compliant data integrity when used with LabX direct pH software and configured user access controls. Instruments meet CE marking requirements under the EU Electromagnetic Compatibility Directive 2014/30/EU and RoHS 2011/65/EU. Optional accessories—including waterproof carrying cases, field calibration kits, and ruggedized sample holders—extend operational validity in ISO 14001-certified environmental sampling workflows.

Software & Data Management

LabX direct pH is a lightweight, Windows-compatible desktop application that establishes secure USB or Bluetooth® communication with SevenGo Pro instruments. It enables automated data capture without manual transcription, enforces electronic signature workflows, and generates compliant reports formatted to internal SOPs or external regulatory templates (e.g., EPA Method 150.1, APHA Standard Methods 4500-H⁺). All raw data—including analog voltage outputs, temperature-corrected values, and electrode diagnostics—are exported in native Excel (.xlsx) or generic CSV format. Audit logs are encrypted and immutable post-export. For networked lab environments, LabX direct pH integrates with LIMS via ODBC drivers and supports scheduled data synchronization to shared network drives. No cloud storage is involved—data sovereignty remains fully under user control.

Applications

• Environmental field testing: pH and conductivity profiling of surface water, groundwater, and effluent streams per EPA SW-846 methods
• Pharmaceutical water system validation: USP Purified Water and Water for Injection (WFI) conductivity verification at multiple distribution points
• Food & beverage QC: titratable acidity screening, brine concentration monitoring, and DO tracking during fermentation or packaging
• Academic teaching labs: quantitative ISE experiments for equilibrium constant determination and Nernst equation validation
• Wastewater treatment plants: real-time DO optimization in activated sludge basins and ORP-guided denitrification control

FAQ

Can the same instrument measure pH, conductivity, and dissolved oxygen simultaneously?
No—each SevenGo Pro unit is hardware-configured for one primary measurement principle (SG, FE, FG, or EL). However, interchangeable SmartSensor™ electrodes allow rapid reconfiguration within the same model family (e.g., switching between pH and ORP electrodes on an SG meter), and multi-parameter probes (e.g., combined pH/DO or pH/conductivity) are available as OEM options.
Is calibration verification traceable to national standards?
Yes—METTLER TOLEDO provides NIST-traceable calibration certificates for reference buffers and conductivity standards. Internal instrument calibration routines store certificate IDs, expiration dates, and technician signatures in the audit trail.
How is electrode performance monitored over time?
The instrument continuously logs electrode impedance, asymmetry potential, and response time during calibration and measurement. Deviations beyond configurable thresholds trigger maintenance alerts and prevent data export until corrective action is logged.
Does the EL series support optical DO sensors for chlorinated water applications?
Yes—the EL models accept both polarographic and luminescent lifetime-based (Luminescent Dissolved Oxygen, LDO) sensors. LDO variants eliminate oxygen consumption artifacts and show no interference from chlorine, H₂S, or heavy metals, complying with ISO 5814:2017 Annex B.
Can LabX direct pH be deployed in a regulated GxP environment?
Yes—when installed on validated Windows workstations with controlled user permissions, LabX direct pH satisfies ALCOA+ principles (Attributable, Legible, Contemporaneous, Original, Accurate) and supports full 21 CFR Part 11 implementation including electronic signatures, role-based access, and audit trail review functions.