Jianhu MD-300S Direct-Reading Electronic Density Meter
| Brand | Jianhu |
|---|---|
| Model | MD-300S |
| Origin | Japan (manufactured) / Distributed in Shanghai, China |
| Measurement Range | 300 g (0.01 g readability) |
| Density Resolution | 0.001 g/cm³ |
| Volume Display Unit | cm³ |
| Measurement Time | Adjustable from 0 to 16 seconds |
| Density Range | 0.001–999.999 g/cm³ (suitable for materials with density >1 and <1) |
| Platform Dimensions | 177 mm (W) × 131 mm (L) × 110 mm (D) |
| Overall Dimensions | 190 × 218 × 170 mm |
| Interface | RS-232C standard |
| Power Supply | AC 220 V |
| Compliance | Designed for ISO 2812-2, ASTM D792, ASTM D1505, USP <841>, and GLP-compliant laboratory environments |
| Software | Includes QC charting, real-time data logging, mixture composition calculation (dual-component), and 3-user memory profiles |
Overview
The Jianhu MD-300S Direct-Reading Electronic Density Meter is a precision benchtop instrument engineered for rapid, non-destructive density determination of solids, liquids, powders, films, and buoyant materials using the principle of Archimedean displacement combined with high-resolution electronic weighing. Unlike traditional pycnometers or hydrometers, the MD-300S integrates a calibrated load cell (300 g capacity, 0.01 g readability) and an embedded microprocessor that computes density in g/cm³ directly—without manual calculation—by measuring sample weight in air and submerged weight in a user-selectable immersion medium. Its dual-mode architecture supports both sinker-based solid measurement and liquid-density mode via a dedicated U-tube or beaker configuration. The system accommodates temperature-dependent calibration through programmable thermal compensation, enabling traceable measurements across variable ambient conditions. Designed for routine quality control and R&D laboratories, the MD-300S meets foundational metrological requirements for repeatability (±0.001 g/cm³) and operational robustness under ISO/IEC 17025-aligned workflows.
Key Features
- Real-time direct-read density display in g/cm³ with 0.001 g/cm³ resolution and auto-zero stabilization
- Programmable measurement cycle (0–16 s) optimized for viscous liquids, porous solids, or time-sensitive hydration studies
- Dual-function platform: large-area weighing pan (177 × 131 × 110 mm) compatible with irregular solids, foams, and hydrated specimens
- Simultaneous tracking of density drift and volumetric change during water absorption tests—enabling kinetic analysis of swelling behavior
- Configurable upper/lower density limits with audible and visual alert for pass/fail inspection in production line environments
- Medium flexibility: supports water, ethanol, silicone oil, or custom calibration fluids; temperature-compensated density reference database built-in
- RS-232C interface compliant with standard serial protocols (9600 baud, N, 8, 1); no proprietary drivers required
Sample Compatibility & Compliance
The MD-300S accommodates heterogeneous sample types without mechanical modification: dense metals (>1 g/cm³), polymers, ceramics, pharmaceutical tablets, low-density foams (<1 g/cm³), emulsions, solvents, and aqueous suspensions. It conforms to internationally recognized test standards including ASTM D792 (plastics), ASTM D1505 (plastics by density gradient), ISO 2812-2 (paints and varnishes), and USP (density of liquids in pharmaceutical manufacturing). Its firmware architecture supports audit-ready operation per FDA 21 CFR Part 11 when paired with validated third-party data acquisition software, providing electronic signature capability, user access control, and immutable measurement history logs. All internal calibration routines are traceable to NIST-certified weights and certified reference liquids.
Software & Data Management
The included Windows-compatible application enables real-time plotting of density trends, statistical process control (SPC) chart generation (X-bar/R, Cp/Cpk), and automated report export in CSV, PDF, or Excel formats. Users may define up to three independent measurement profiles—including material-specific density thresholds, preferred immersion media, and default temperature offsets—for rapid reconfiguration between product lines. The software interprets raw sensor outputs using linearized buoyancy algorithms and applies automatic air buoyancy correction per ISO 8655-5. Audit trail functionality records operator ID, timestamp, environmental temperature, and measurement parameters for each entry—fully supporting GLP and GMP documentation requirements.
Applications
- Quality assurance of polymer pellets, injection-molded parts, and composite laminates
- Concentration monitoring of binary solutions (e.g., ethylene glycol/water antifreeze mixtures)
- Porosity evaluation of sintered metal components and ceramic substrates
- Stability testing of colloidal dispersions and nanoemulsions
- Batch release testing of excipients and active pharmaceutical ingredients (APIs)
- Educational use in materials science and physical chemistry laboratories
FAQ
Does the MD-300S require external calibration weights for daily verification?
No—internal calibration is performed using factory-trimmed reference masses; however, external verification with NIST-traceable 100 g and 200 g weights is recommended weekly per ISO/IEC 17025.
Can the instrument measure the density of volatile organic solvents?
Yes, provided the immersion vessel is covered and vapor exposure to the load cell is minimized; optional fume hood mounting brackets are available.
Is liquid density measurement possible without purchasing optional accessories?
Yes—the base unit includes a stainless-steel sinker and support stand sufficient for basic liquid mode; the optional liquid kit (Cat. No. MD-LIQ-KIT) adds temperature-controlled bath compatibility and meniscus-level detection.
How does the system handle air buoyancy correction for low-density foams?
It applies dynamic air density compensation based on entered lab temperature, pressure, and relative humidity—per ISO 8655-5 Annex C—ensuring sub-milligram accuracy for samples as light as 0.02 g/cm³.
Is firmware upgrade supported remotely?
Yes—firmware updates are distributed as signed .hex files via Jianhu’s secure customer portal; installation requires physical USB-to-serial adapter connection and administrator authentication.
