AND GF-203A Precision Top-Loading Balance (220 g / 0.001 g)

Overview

The AND GF-203A is a high-reliability precision top-loading balance engineered for routine quantitative weighing in quality control laboratories, academic research settings, and pharmaceutical production environments. It operates on electromagnetic force compensation (EMFC) principle—where the mass-induced displacement of the weighing pan is counteracted by a precisely regulated electromagnetic current—and converts this equilibrium condition into a stable digital readout with 0.001 g resolution. Designed for ISO/IEC 17025-compliant workflows, the GF-203A delivers consistent performance under standard ambient conditions (20 ± 5 °C, < 80 % RH non-condensing), with built-in environmental compensation for minor temperature drift and air current fluctuations. Its compact footprint and vertical column architecture minimize bench space requirements while maintaining mechanical stability essential for reproducible measurements.

Key Features

• Electromagnetic force compensation sensor with auto-zero tracking and dynamic damping control ensures rapid stabilization—typically ≤1.0 second for full-scale loads, and as fast as 0.8 seconds for small reference masses (e.g., 5 g).
• External calibration capability using certified weights traceable to NIST or JCSS standards supports audit-ready documentation per ISO 9001, ISO/IEC 17025, and FDA 21 CFR Part 11 requirements.
• Stainless steel weighing pan (128 × 128 mm) with raised perimeter edge prevents sample spillage and facilitates easy cleaning—critical for GMP-regulated environments handling active pharmaceutical ingredients (APIs) or hazardous compounds.
• Backlit LCD display with large, high-contrast digits (18 mm height) enables clear readability under varied lighting conditions, including laminar flow hoods and glove boxes.
• Integrated RS-232 interface allows direct connection to laboratory information management systems (LIMS), electronic lab notebooks (ELN), or statistical process control (SPC) software without third-party adapters.
• Robust housing constructed from ABS polymer with reinforced base provides resistance to mechanical shock and static discharge—validated per IEC 61326-1 for electromagnetic compatibility in shared instrumentation labs.

Sample Compatibility & Compliance

The GF-203A accommodates solid, granular, and low-viscosity liquid samples within its 220 g capacity limit. Its open-top design permits unrestricted access for spatula-based loading, volumetric flask placement, or tare container integration. The balance meets international metrological standards including OIML R 76-1 (Class II accuracy), JIS B 7721 (Japanese Industrial Standard for non-automatic weighing instruments), and EN 45501 (European harmonized standard). For regulated industries, it supports GLP/GMP documentation through optional audit-trail-enabled firmware (requires AND WinCT software v4.0+), enabling timestamped calibration logs, user authentication, and change history retention.

Software & Data Management

Data output follows standard ASCII protocol via RS-232, compatible with common serial-to-USB converters and legacy lab systems. AND’s WinCT software (Windows-compatible, free download) provides real-time data streaming, automatic CSV export, statistical analysis (mean, SD, CV%), and customizable report templates aligned with ISO 10012 and USP . All transmitted values include unit suffix (g), polarity sign, and status flags (e.g., “ST” for stable, “OL” for overload). No cloud dependency or proprietary drivers are required—ensuring long-term interoperability and IT security compliance.

Applications

• Pharmaceutical formulation: Accurate dispensing of excipients and APIs during tablet development and batch release testing.
• Chemical synthesis: Stoichiometric reagent weighing prior to reaction setup; yield determination post-purification.
• Materials science: Density calculation via mass/volume correlation using calibrated volumetric glassware.
• Food safety labs: Moisture content analysis (gravimetric loss-on-drying per AOAC 950.46), ash determination (AOAC 942.05).
• Environmental testing: Weighing filter papers pre- and post-particulate collection (EPA Method 201A, ISO 12141).
• Academic teaching labs: Fundamental instruction in measurement uncertainty, significant figures, and error propagation principles.

FAQ

What calibration weights are required for the GF-203A?
A single 200 g Class M2 or better certified weight (traceable to national metrology institute) is sufficient for full-range verification and adjustment.
Does the GF-203A support internal calibration?
No—it is externally calibrated only, which enhances long-term stability and simplifies regulatory validation by eliminating motorized calibration mechanisms subject to wear.
Can the balance be used in a fume hood?
Yes, provided airflow velocity at the pan surface remains below 0.2 m/s and ambient temperature is stabilized; optional draft shield (AND part # SH-128) is recommended for optimal performance.
Is the RS-232 interface opto-isolated?
Yes—the interface includes galvanic isolation to prevent ground-loop interference when connected to PCs or PLCs in electrically noisy industrial settings.
How is repeatability verified during routine operation?
By performing ≥10 consecutive weighings of a stable test weight (e.g., 100 g stainless steel standard) under identical environmental conditions; observed standard deviation must not exceed ±0.001 g.