Beiguang Jingyi GDAT Series High-Frequency Q-Meter for Dielectric Constant and Loss Tangent Measurement of Plastics and Elastomers

Overview

The Beiguang Jingyi GDAT Series High-Frequency Q-Meter is an engineered precision instrument designed for the quantitative determination of dielectric constant (ε_r) and dissipation factor (tan δ) of insulating polymeric and elastomeric materials—particularly plastics, rubber compounds, ceramic composites, and advanced non-metallic dielectrics. It operates on the principle of high-frequency series resonance, leveraging a digitally stabilized RF signal source and automated capacitance-frequency tracking to deliver traceable, repeatable measurements across a broad frequency spectrum (10 kHz to 160 MHz). Unlike broadband impedance analyzers or low-frequency LCR meters, the GDAT series employs resonant cavity methodology optimized for high-Q material characterization—enabling accurate extraction of intrinsic dielectric loss mechanisms in bulk samples under controlled field conditions. Its architecture conforms to the measurement philosophy outlined in GB/T 1409–2006, which aligns with international practices for evaluating electrical insulation performance at power, audio, and radio frequencies—including meter- and decimeter-wave bands.

Key Features

• Wide-frequency coverage: 10 kHz – 160 MHz, segmented into four calibrated bands with automatic band switching and digital frequency synthesis (DDS)
• Q-value measurement range: 2 to 1023, with five manual/auto-selectable ranges (30, 100, 300, 1000) and real-time auto-ranging capability
• Integrated dual-electrode test fixture system: Independent cylindrical and parallel-plate electrode configurations—ensuring compliance with ASTM D150 and IEC 60250 sample geometry requirements
• Microprocessor-controlled tuning: ATMega128-based core with stepper-motor-driven main capacitor (CT), enabling precise, backlash-free capacitance positioning and automatic resonance search (frequency sweep or capacitance sweep mode)
• High-stability signal generation: Automatic amplitude control (AAC) loop maintains ±0.1 dB output level stability over temperature and load variations
• Four-line backlit LCD interface: Displays real-time parameters including excitation frequency, CT value, inductance (L_x), Q-value, Q-range status, auto-search indicators, and pass/fail comparison status
• Residual parameter compensation: Factory-calibrated correction for residual inductance (L₀ ≈ 7–26 nH) and stray capacitance ensures measurement integrity below 1 µH and sub-pF levels

Sample Compatibility & Compliance

The GDAT Series supports standardized dielectric testing of solid, rigid, and flexible polymer specimens—including thermoplastics (e.g., PVC, PE, PP), thermosets (e.g., epoxy, phenolic), elastomers (e.g., silicone, EPDM), and ceramic-polymer composites. Sample mounting follows GB/T 1409–2006 and ISO 2577 protocols: flat-surface specimens are measured using parallel-plate electrodes (diameter 25 mm or 50 mm, adjustable gap), while tubular or irregular geometries utilize coaxial cylindrical electrodes. The instrument meets electromagnetic compatibility (EMC) requirements per GB/T 18268.1–2010 (IEC 61326-1) and safety standards per GB 4793.1–2007 (IEC 61010-1). While not certified to FDA 21 CFR Part 11, its data logging and pass/fail threshold functions support GLP-compliant documentation when integrated with external audit-trail software.

Software & Data Management

The GDAT Series operates as a standalone benchtop instrument with no embedded PC or proprietary software stack. All measurement logic, calibration routines, and user interface functions are implemented in firmware. Data output is limited to on-screen display and audible pass/fail feedback (via built-in buzzer). For laboratory integration, users may record results manually or via external RS-232 (optional) or analog voltage output (0–5 V proportional to Q or tan δ). No cloud connectivity, remote control API, or database export is provided—consistent with industrial QA/QC environments requiring deterministic, validation-ready operation. Calibration records, Q-value tolerance settings, and frequency-specific correction coefficients are retained in non-volatile memory and survive power cycles.

Applications

• Quality assurance of polymer insulators used in cable jacketing, transformer bushings, and printed circuit board substrates
• R&D evaluation of dielectric filler dispersion (e.g., BaTiO₃, SiO₂) in rubber matrices for tunable permittivity
• Process monitoring of crosslink density in vulcanized elastomers via tan δ temperature sweeps (when paired with environmental chamber)
• Characterization of microwave-absorbing composites for aerospace shielding applications
• Validation of high-frequency stability in antenna encapsulants and radome materials
• Academic research on relaxation dynamics in amorphous polymers using frequency-domain dielectric spectroscopy (FDS) principles

FAQ

What standards does the GDAT Series comply with?

It implements the test methodology specified in GB/T 1409–2006, which is technically equivalent to ASTM D150 and IEC 60250 for dielectric constant and loss tangent measurement. Frequency accuracy and Q-value uncertainty are validated against national metrology institute traceable reference inductors (e.g., BQG-2 standard coil set).

Can it measure liquid or powder samples?

No—the GDAT Series is configured exclusively for solid-state dielectric testing using fixed-geometry electrodes. Liquids require guarded electrode cells; powders demand pelletization and sintering prior to measurement.

Is calibration required before each use?

A 30-minute warm-up is mandatory for thermal stabilization. Daily verification using a reference inductor (e.g., LKI-1 set) is recommended for production environments. Full recalibration is advised every 12 months or after mechanical shock.

Does it support temperature-controlled measurements?

The base unit has no integrated temperature stage. However, the electrode fixtures are compatible with third-party environmental chambers (−40 °C to +150 °C) when cabling and grounding are implemented per IEC 60601-1 leakage current limits.

How is measurement uncertainty quantified?

Per GB/T 1409–2006 Annex B, total Q-value uncertainty comprises: ±5% inherent error (10 kHz–10 MHz), ±7% working error (10 kHz–10 MHz), ±6% inherent error (10 MHz–160 MHz), and ±8% working error (10 MHz–160 MHz), plus ±2% of full-scale reading. Residual parameter corrections further reduce systematic bias by up to 15% in low-inductance regimes.