Hanuo HN-018TD-II Transparent Glass Low-Temperature Circulating Bath

Overview

The Hanuo HN-018TD-II Transparent Glass Low-Temperature Circulating Bath is a precision-engineered thermal management system designed for laboratories requiring high-fidelity temperature control, real-time visual monitoring, and stable thermal homogeneity across extended operation cycles. Utilizing a dual-mode thermoelectric compression refrigeration and resistive heating architecture, the unit maintains setpoint accuracy within ±0.05 °C over its full operational range of 0–100 °C. Its defining feature—a triple-sided transparent borosilicate glass bath—enables unobstructed optical access to sample behavior, fluid dynamics, colorimetric transitions, and reaction kinetics without compromising thermal integrity. This configuration supports applications where in situ observation is critical: enzyme activity assays under controlled thermal ramping, polymerization onset detection, calibration of reference thermometers (per ASTM E77 and ISO 17025 Annex C), and validation of temperature-sensitive sensor responses.

Key Features

• Triple-side transparent borosilicate glass tank (chemical-resistant, low thermal expansion) for direct visual inspection of samples, fluid circulation patterns, and reaction progress
• PID digital temperature controller with 0.01 °C display resolution and adaptive tuning algorithms to minimize overshoot and stabilize temperature within <15 minutes after setpoint change
• Internal recirculation system with corrosion-resistant stainless-steel impeller and optimized flow path geometry to ensure radial and axial thermal uniformity ≤±0.03 °C across the 18 L working volume
• Compact desktop footprint (W×D×H ≈ 320×300×480 mm) suitable for fume hoods, biosafety cabinets, and benchtop analytical workstations
• Refrigeration capacity rated at 200 W at 0 °C ambient; heating power 1200 W with thermal cut-off protection and dry-run prevention circuitry
• Front-panel interface with dual-line LED display showing real-time bath temperature and user-defined setpoint; tactile membrane keys with haptic feedback

Sample Compatibility & Compliance

The HN-018TD-II accommodates standard immersion probes (e.g., Pt100, thermistor, or NIST-traceable RTDs), glassware up to Ø150 mm, and reaction vessels with vertical clearance up to 350 mm. The bath is compatible with water, ethanol–water mixtures, silicone oils (up to 100 cSt), and low-viscosity glycol solutions. It conforms to electrical safety standards IEC 61010-1:2010 and EMC directive 2014/30/EU. While not FDA 21 CFR Part 11–certified out-of-box, its deterministic temperature logging capability (via optional RS485/Modbus interface) supports audit-ready data capture when integrated into validated laboratory information management systems (LIMS) compliant with ISO/IEC 17025 and GxP requirements.

Software & Data Management

The unit operates autonomously via embedded firmware but supports external data acquisition through an optional RS485 port (Modbus RTU protocol). When connected to PC-based platforms such as LabVIEW, MATLAB, or custom Python scripts using PySerial, users can log timestamped temperature readings at configurable intervals (1–60 s), trigger alarms on deviation thresholds, and export CSV-formatted datasets with metadata (setpoint, actual temp, timestamp, status flags). No proprietary software installation is required; all communication follows open industrial protocols to facilitate integration into existing QA/QC workflows and automated calibration records.

Applications

• Calibration of liquid-in-glass thermometers, digital thermometers, and infrared sensors against reference standards (ASTM E220, ISO 17025 Clause 6.5)
• Temperature-controlled enzymatic assays and protein denaturation studies requiring optical clarity and thermal stability
• Thermal validation of viscometers, densitometers, and refractometers during instrument qualification (IQ/OQ)
• Controlled cooling/heating cycles for crystallization screening and phase transition analysis in pharmaceutical development
• Stabilization of laser sources, photodetectors, and optical benches in metrology labs where thermal drift must remain sub-mK
• Supporting ASTM D2857 (FTIR cell temperature control) and USP environmental monitoring system validation

FAQ

What is the maximum allowable working fluid viscosity for stable internal circulation?
The pump is optimized for fluids with kinematic viscosity ≤100 cSt at operating temperature; higher viscosities require external circulation or reduced bath volume.
Can this bath be used for external temperature control via an external loop?
No—the HN-018TD-II features internal circulation only; models with external port capability (e.g., HN-018TD-EX) are available upon request.
Is the glass tank resistant to hydrochloric acid or sodium hydroxide solutions?
Borosilicate glass (Schott Duran® equivalent) resists short-term exposure to ≤10% HCl and ≤5% NaOH at room temperature; prolonged contact or elevated temperatures require compatibility testing.
Does the unit include NIST-traceable calibration documentation?
Factory calibration certificates (with uncertainty budget per ISO/IEC 17025) are provided; NIST-traceable field calibration requires third-party service.
What is the typical warm-up time from 0 °C to 37 °C with a full 18 L load?
Approximately 22–26 minutes under standard ambient conditions (23 °C, 50% RH), verified per ASTM E29–23 Annex A3 methodology.