Precisa 321LS Series Analytical Balance

Overview

The Precisa 321LS Series Analytical Balance is an industrial-grade precision weighing instrument engineered for laboratories and production environments requiring high reproducibility, long-term stability, and regulatory compliance. Built upon electromagnetic force compensation (EMFC) technology, the 321LS delivers rapid stabilization and exceptional sensitivity across its full capacity range—up to 320 g—with a readability of 0.1 mg. Unlike strain-gauge-based platforms, the proprietary EMFC sensor architecture minimizes mechanical wear, reduces thermal drift, and extends service intervals without compromising metrological integrity. The balance is manufactured under Precisa’s global quality framework in Shanghai, adhering to the structural and performance requirements of DIN EN 45501—the European standard governing non-automatic weighing instruments—and designed for seamless integration into regulated workflows governed by GMP, GLP, and ISO/IEC 17025.

Key Features

• Electromagnetic force compensation (EMFC) transducer with integrated temperature compensation—ensures consistent accuracy across ambient fluctuations from 10 °C to 30 °C.
• Smart Calibration System (SCS): Fully automated internal calibration triggered by user-defined time intervals or real-time temperature deviation thresholds (±1.5 °C), eliminating manual recalibration drift.
• VFD (Vacuum Fluorescent Display) with graphical capacity bar: Provides intuitive visual feedback on load distribution, overload warning, and dynamic stability indicators.
• IP65-rated enclosure: Dust-tight and protected against low-pressure water jets—enabling safe operation in humid, particulate-rich, or washdown-prone environments.
• Full cast-aluminum housing: Rigid monolithic upper and lower chassis suppress vibration transmission, shield against electromagnetic interference (EMI), and resist corrosion from common laboratory solvents and cleaning agents.
• Front-mounted leveling mechanism with integrated tilt sensor: Enables rapid, tool-free adjustment and continuous real-time monitoring of level status—critical for maintaining measurement traceability.
• Embedded real-time clock (RTC) with audit-trail logging: Timestamps all calibration events, zeroing actions, and configuration changes per GMP/GLP documentation requirements.

Sample Compatibility & Compliance

The 321LS supports diverse sample forms—including powders, granules, liquids in tared vessels, and small solid components—without compromising repeatability or linearity. Its draft shield compatibility (optional accessory) ensures stable readings under variable airflow conditions. All firmware and hardware configurations comply with DIN EN 45501 for accuracy class II (analytical use), and the device supports full 3Q qualification (IQ/OQ/PQ) documentation packages. Data integrity meets FDA 21 CFR Part 11 criteria when used with validated LIMS or PC software via RS232 or HID-compliant USB interface. The balance is preconfigured for electronic signature support, event logging, and user-access-level management—facilitating routine audits and regulatory inspections.

Software & Data Management

Data output is supported via dual protocols: RS232 serial interface (with configurable baud rate, parity, and stop bits) for legacy systems and HID-class USB for plug-and-play integration with Windows/macOS/Linux PCs—requiring no driver installation. All weight values transmit directly into Excel, LIMS, or ERP systems as ASCII strings, minimizing transcription errors. Internal memory stores up to 1,000 timestamped records (weight + metadata), exportable via RS232. Optional PC software provides advanced reporting, statistical analysis (mean, SD, CV%), trend visualization, and automated certificate generation aligned with ISO/IEC 17025 clause 7.7.

Applications

• Quantitative analytical chemistry: Sample preparation, titrant standardization, and reference material dispensing.
• Pharmaceutical QC: Active pharmaceutical ingredient (API) assay, excipient blending verification, and tablet weight uniformity testing per USP & Ph. Eur. guidelines.
• Materials science: Density determination (via sink-float method), powder flow characterization, and catalyst loading precision.
• Food & beverage QA: Net content verification, ingredient proportioning, and nutritional labeling compliance.
• Education & research labs: Teaching metrology principles, gravimetric analysis, and method validation studies.

FAQ

Does the 321LS meet ISO/IEC 17025 requirements for accredited testing laboratories?

Yes—the balance supports documented traceability, uncertainty estimation, and calibration interval justification per ISO/IEC 17025:2017 Clause 6.4 and 6.5. Its SCS logs are admissible as evidence during accreditation audits.
Can the internal calibration be scheduled to run automatically at startup?

Yes—calibration triggers can be configured for power-on, time-of-day, or temperature delta events, ensuring continuous metrological readiness.
Is the USB interface compatible with modern operating systems without third-party drivers?

Yes—it operates as a Human Interface Device (HID), transmitting weight data as keyboard input—fully compatible with Windows 10/11, macOS Monterey+, and major Linux distributions.
What is the recommended calibration frequency under GLP conditions?

Per GLP Annex 1, daily verification using certified weights is advised; internal calibration should be performed before first use and after any environmental shift exceeding ±1.5 °C.
Does the 321LS support density determination with built-in calculation routines?

Yes—it includes a dedicated density mode that computes solid density using air buoyancy correction and user-input reference fluid density (e.g., ethanol, water), compliant with ASTM D792 and ISO 1183-1.