Hanuo HN-10A High-Precision Calibration-Grade Low-Temperature Circulating Bath
| Brand | Hanuo |
|---|---|
| Origin | Shanghai, China |
| Model | HN-10A |
| Bath Volume | 18 L |
| Temperature Range | -10 °C to 90 °C |
| Temperature Stability | ±0.01 °C over 30 min |
| Temperature Uniformity | ≤0.01 °C |
| Circulation Type | Internal Only |
| Control Mode | Refrigeration & Heating |
| Working Medium | Anhydrous Ethanol or Industrial Alcohol/Water |
| Power Supply | 220 V / 50 Hz |
| Total Power | 1.5 kW |
| Net Weight | 120 kg |
| Compliance | Designed for metrological calibration per JJG 2074–2016 (China), compatible with ISO/IEC 17025 traceability requirements |
Overview
The Hanuo HN-10A High-Precision Calibration-Grade Low-Temperature Circulating Bath is an engineered thermal reference system designed specifically for metrological temperature calibration in national and industrial calibration laboratories. It operates on the principle of active dual-mode (refrigeration + heating) temperature control within a thermally insulated stainless-steel bath chamber, enabling stable, uniform, and reproducible thermal environments across a wide operational range from –10 °C to +90 °C. Unlike general-purpose water/oil baths, the HN-10A is optimized for full-immersion calibration applications—ensuring minimal axial and radial thermal gradients (<0.01 °C) throughout its defined working zone (Φ130 × 480 mm). Its architecture complies with fundamental requirements for secondary standard temperature calibration equipment as outlined in JJG 2074–2016 (Calibration Specification for Liquid-in-Glass Thermometers) and supports traceable verification against national primary standards under ISO/IEC 17025-accredited quality management systems.
Key Features
- Fully welded 304 stainless-steel construction for both outer casing and inner bath vessel—resistant to corrosion from anhydrous ethanol, industrial alcohol, and aqueous media;
- PID-based digital temperature controller with high-resolution (0.001 °C) setpoint resolution and adaptive tuning algorithms for rapid stabilization and long-term drift suppression;
- Imported high-efficiency heating elements and R22 refrigerant-based cooling circuit, delivering precise bidirectional thermal control without external chiller dependency;
- Internal recirculation pump ensures homogeneous temperature distribution across the entire working volume (18 L), validated via multi-point platinum resistance thermometer (PRT) mapping;
- Thermal insulation design minimizes ambient influence—operational performance guaranteed at ambient temperatures ≤30 °C;
- Front-panel interface with real-time display of setpoint, measured bath temperature, stability status, and system fault diagnostics.
Sample Compatibility & Compliance
The HN-10A accommodates full-immersion calibration of primary and secondary temperature standards including mercury-in-glass thermometers (Class I/II), Beckmann differential thermometers, industrial Pt100 RTDs (per IEC 60751), and standard Cu–Constantan thermocouples (Type T). Its working zone dimensions (Φ130 × 480 mm) conform to national metrological guidelines for minimum immersion depth and lateral clearance. The unit is routinely deployed in CNAS-accredited calibration labs for verification tasks aligned with GB/T 28897–2012 (Industrial Platinum Resistance Thermometers) and supports audit readiness for GLP and GMP environments where thermal validation records must meet FDA 21 CFR Part 11 data integrity expectations (when paired with compliant data logging software).
Software & Data Management
While the HN-10A operates as a standalone hardware platform, it features RS232 and optional RS485 communication interfaces for integration into laboratory-wide calibration management systems. When connected to validated third-party software (e.g., MET/CAL®, DryCal®, or custom LabVIEW-based DAQ platforms), the bath enables automated temperature ramping, dwell sequencing, and timestamped data capture—including real-time stability metrics (±0.01 °C over 30 minutes) and thermal uniformity reports. All logged parameters support CSV export and are structured to satisfy ISO/IEC 17025 clause 7.7 (Reporting of Results) and clause 8.4 (Records for Calibration Activities).
Applications
- Primary and secondary calibration of liquid-in-glass, bimetallic, and electronic thermometers in metrology institutes;
- Verification and adjustment of process temperature sensors prior to field deployment in pharmaceutical, chemical, and food manufacturing;
- Reference source for thermal characterization of materials (e.g., coefficient of thermal expansion studies);
- Stable cold/hot source for controlled reaction kinetics experiments requiring sub-0.02 °C thermal repeatability;
- Support equipment for thermocouple wire annealing, RTD stability testing, and sensor hysteresis evaluation protocols.
FAQ
What temperature media are compatible with the HN-10A bath?
Anhydrous ethanol is recommended for operation below 0 °C; industrial alcohol or deionized water may be used above 0 °C. Viscosity and flash point constraints must be observed per manufacturer’s safety guidelines.
Is external circulation supported?
No—the HN-10A provides internal recirculation only. For external loop applications (e.g., jacketed reactors), consider the Hanuo HN-10A-EX variant with integrated outlet/inlet ports.
Can the unit be validated for ISO/IEC 17025 accreditation?
Yes—its documented temperature stability (±0.01 °C/30 min), uniformity (≤0.01 °C), and traceable control architecture enable inclusion in scope assessments when operated with certified reference thermometers and documented SOPs.
What maintenance intervals are recommended?
Refrigerant pressure and pump seal integrity should be verified annually; heating element resistance and PID controller calibration are advised every 24 months under continuous use.
Does the HN-10A comply with electromagnetic compatibility (EMC) directives?
It meets GB/T 18268.1–2010 (equivalent to IEC 61326-1) for laboratory equipment, ensuring reliable operation in shared instrumentation environments without signal interference.
