METTLER TOLEDO LE104E Precision Analytical Balance
| Brand | METTLER TOLEDO |
|---|---|
| Origin | Beijing, China |
| Model | LE104E |
| Type | Analytical Balance |
| Maximum Capacity | 220 g |
| Readability | 0.1 mg |
| Repeatability | 0.1 mg |
| Calibration | External |
| Pan Diameter | 80 mm |
| Power Supply | AC Mains |
Overview
The METTLER TOLEDO LE104E Precision Analytical Balance is an entry-level analytical balance engineered for laboratories requiring reliable, traceable mass measurements with 0.1 mg readability and 220 g maximum capacity. It operates on electromagnetic force compensation (EMFC) principle — the industry-standard measurement technology for high-precision balances — ensuring stable, drift-resistant performance under typical laboratory environmental conditions. Designed specifically for routine QC, academic teaching labs, and pharmaceutical pre-formulation workflows, the LE104E delivers metrologically sound results aligned with ISO/IEC 17025 requirements for calibration and verification. Its robust mechanical architecture, including a monolithic weighing cell and draft shield-compatible design, minimizes sensitivity to air currents and vibration — critical for consistent repeatability at the 0.1 mg level.
Key Features
- 0.1 mg readability with 220 g maximum capacity, optimized for applications requiring four-decimal-place precision
- Electromagnetic force compensation (EMFC) transducer delivering high linearity, low hysteresis, and long-term stability
- External calibration capability using certified weights (e.g., Class E2 or better), supporting documented calibration intervals per ISO 9001 and GLP protocols
- 80 mm stainless steel weighing pan with smooth, non-porous surface for easy cleaning and residue-free operation
- AC mains-powered operation with integrated overload protection and automatic power-saving mode after user-defined idle time
- Front-panel interface with intuitive LED display and tactile push-button controls — no touchscreen dependency, ensuring reliability in humid or solvent-exposed environments
Sample Compatibility & Compliance
The LE104E accommodates standard sample containers including weighing boats, vials, crucibles, and filter papers within its 80 mm pan diameter. Its open-frame design allows compatibility with optional draft shields (sold separately) for volatile or hygroscopic samples. The balance meets essential regulatory expectations for basic analytical instrumentation: it supports manual calibration documentation required under FDA 21 CFR Part 11 (when used in conjunction with controlled lab procedures), complies with ISO 9001:2015 clause 7.1.5 for monitoring and measuring resources, and satisfies ASTM E898–22 guidelines for verification of analytical balance performance. While not equipped with built-in audit trail or electronic signature functionality, its external calibration workflow enables full traceability when integrated into GxP-aligned SOPs.
Software & Data Management
The LE104E features a direct RS232 serial interface for seamless connection to PCs, LIMS, or ELN systems without proprietary drivers. ASCII-based output format ensures compatibility with common data acquisition tools (e.g., Microsoft Excel, LabArchives, or custom Python scripts). All weight readings are transmitted with timestamp (if host system provides real-time clock), unit designation (g), and status flags (e.g., “STABLE”, “OVERLOAD”). No internal memory or onboard software is included — this minimalist architecture enhances device longevity, simplifies validation, and avoids firmware update dependencies. For laboratories implementing 21 CFR Part 11 compliance, external data capture via validated serial logging software fulfills electronic record integrity requirements.
Applications
- Pharmaceutical quality control: active pharmaceutical ingredient (API) weighing, excipient dispensing, and reference standard preparation per USP & EP general chapters
- Academic chemistry and biology labs: molar mass calculations, solution preparation, and stoichiometric reagent dosing
- Food testing laboratories: moisture content determination (via gravimetric loss-on-drying), ash analysis, and nutrient labeling verification
- Materials science: powder density characterization, catalyst loading quantification, and thin-film deposition mass tracking
- Environmental testing: filter weighing for particulate matter (PM2.5/PM10) analysis in accordance with EPA Method IO-4.2
FAQ
What calibration standards are recommended for the LE104E?
Class E2 stainless steel weights (certified to OIML R111) are recommended for external calibration; calibration should be performed at least daily or before each critical weighing session.
Does the LE104E support internal calibration?
No — the LE104E relies exclusively on external calibration using traceable reference masses.
Can the balance be used in a fume hood?
Yes, provided a compatible draft shield is installed and ambient temperature remains stable (±2 °C/hour); avoid placement directly in airflow paths.
Is the RS232 interface compatible with modern Windows/macOS systems?
Yes — using a standard USB-to-RS232 adapter and terminal emulation software (e.g., Tera Term or PuTTY), no vendor-specific drivers are required.
What is the warm-up time required before first use?
Minimum 30 minutes at stable room temperature (20–25 °C) is recommended to achieve thermal equilibrium of the EMFC sensor and ensure optimal repeatability.
