Longteng ESJ208-S 0.01 mg Analytical Balance

Overview

The Longteng ESJ208-S is a high-precision dual-range analytical balance engineered for laboratories requiring trace-level mass measurement with metrological rigor. Operating on the principle of electromagnetic force compensation (EMFC), it delivers stable, drift-compensated readings across two distinct readability modes: 0.01 mg (10 µg) in the lower range (up to 80 g) and 0.1 mg (100 µg) in the extended range (up to 200 g). This dual-range architecture enables users to maintain optimal sensitivity for microsample analysis while retaining flexibility for larger container tare weights—critical for pharmaceutical formulation, reference standard preparation, and gravimetric titration workflows. The balance features a rear-mounted EMFC sensor, which minimizes mechanical hysteresis and enhances long-term stability under variable thermal loads. Its robust aluminum alloy housing and sealed internal calibration mechanism ensure consistent performance in non-climate-controlled lab environments typical of QC labs, university research facilities, and contract testing organizations.

Key Features

• Rear-mounted electromagnetic force compensation sensor for high linearity and minimal creep
• Triple-door draft shield with wide-open access and spacious weighing chamber (Φ90 mm stainless steel pan)
• Automatic internal calibration with integrated stainless steel reference weights—triggered manually, on schedule, or in response to temperature fluctuations ≥0.5 °C
• Backlit LCD display with adjustable brightness for optimal legibility under low-light or high-ambient-light conditions
• Dual readability switching (0.01 mg / 0.1 mg) without manual range selection—automatically optimized per load
• Comprehensive error mitigation: overload/underload alerts, full-scale tare, temperature compensation algorithm, and real-time drift correction
• RS232 serial interface compliant with standard ASCII protocol for seamless integration with LIMS, ELN, or statistical process control software

Sample Compatibility & Compliance

The ESJ208-S accommodates a broad spectrum of sample forms—including powders, crystals, liquids in volumetric flasks, and small solid components—thanks to its large-diameter pan and unobstructed chamber geometry. It supports optional accessories such as a density determination kit (requiring auxiliary software and calibrated sinker) and a below-balance weighing hook for suspended measurements (e.g., magnetic susceptibility or buoyancy-corrected density). From a regulatory standpoint, the balance’s automatic calibration log, user-accessible audit trail (via RS232 timestamped output), and deterministic repeatability meet foundational requirements for ISO/IEC 17025-accredited testing labs. While not pre-certified to FDA 21 CFR Part 11, its data export functionality and internal calibration traceability support validation protocols required under GxP frameworks when deployed with documented SOPs and periodic external verification.

Software & Data Management

Data output follows standard RS232 ASCII format (9600 baud, N, 8, 1), enabling direct ingestion into spreadsheet applications, custom Python-based QA dashboards, or enterprise-grade laboratory information management systems (LIMS). Each transmitted record includes timestamp (system-generated), net weight, unit identifier, and status flags (e.g., “CAL”, “OVER”, “TARE”). No proprietary software is bundled; however, the device is compatible with common terminal emulators (e.g., Tera Term, PuTTY) for real-time monitoring and batch logging. For regulated environments, users may implement third-party middleware to enforce electronic signatures, audit trails, and data integrity controls aligned with ALCOA+ principles.

Applications

• Gravimetric preparation of certified reference materials (CRMs) and working standards
• Weighing of active pharmaceutical ingredients (APIs) in dosage form development per USP & Ph. Eur. guidelines
• Residue-on-ignition (ROI) and loss-on-drying (LOD) determinations requiring sub-0.1 mg resolution
• Calibration of pipettes and volumetric glassware using water weighing methods (ISO 8655-6)
• Quality control of catalysts, nanomaterials, and thin-film coatings where mass uniformity at µg-level is critical
• Teaching laboratories requiring intuitive operation and repeatable pedagogical demonstrations of metrological concepts

FAQ

What does “dual-range” mean for the ESJ208-S?
It operates at two distinct readability levels: 0.01 mg up to 80 g, and 0.1 mg from 80 g to 200 g—automatically selected based on load magnitude to preserve accuracy and dynamic range.
Is external calibration required?
No external calibration is needed for routine operation due to the built-in automatic internal calibration system; however, periodic verification using NIST-traceable weights is recommended per ISO/IEC 17025 clause 6.5.
Can this balance be used in a fume hood?
Yes—its sealed sensor housing and draft shield design allow safe operation in low-airflow chemical containment enclosures, provided ambient temperature remains within 15–30 °C and relative humidity stays below 80% RH non-condensing.
Does it support GLP-compliant data recording?
It provides timestamped, ASCII-formatted output suitable for GLP-compliant documentation when paired with validated data capture software and controlled user access procedures.
What is the warranty coverage?
Longteng offers a 24-month limited warranty covering parts and labor for defects in materials and workmanship under normal laboratory use conditions.