Hanuo HT856 Infrared Calibration Blackbody Constant-Temperature Bath

Overview

The Hanuo HT856 Infrared Calibration Blackbody Constant-Temperature Bath is a precision-engineered thermal reference source designed for metrological traceability in radiometric and thermometric calibration workflows. It functions as a high-emissivity blackbody cavity immersed in a temperature-controlled liquid medium—typically silicone oil or water—enabling stable, uniform, and reproducible thermal fields across its operational range of −5 °C to 100 °C. Unlike general-purpose thermostatic baths, the HT856 integrates a calibrated blackbody cavity with an effective spectral emissivity of ≥0.99 (measured at wavelengths relevant to common infrared thermometers, typically 3–14 µm), making it suitable as a primary reference standard for calibrating non-contact radiation thermometers, infrared pyrometers, thermal imaging systems, and radiometric sensors. Its operation is grounded in Planck’s law of blackbody radiation and the principle of thermal equilibrium, where the cavity’s surface temperature—accurately maintained and measured by a Pt100 resistance thermometer—is directly correlated to its emitted spectral radiance. This enables NIST-traceable calibration in accordance with ISO/IEC 17025-accredited laboratories and supports compliance with national metrological standards including JJG 856–2015 (Verification Regulation for Working Radiation Thermometers) and JJF 1030–2010 (Technical Performance Testing Specification for Constant-Temperature Baths).

Key Features

• High-stability temperature control with ±0.01 °C short-term stability over 30 minutes—engineered for calibration-grade repeatability
• Integrated blackbody cavity with verified emissivity ≥0.99, fabricated from high-thermal-conductivity anodized aluminum and optimized geometry to minimize reflection losses
• PID-based digital temperature regulation with auto-tuning capability and real-time deviation compensation
• Liquid-immersed Pt100 sensor (Class A, IEC 60751) mounted directly within the cavity wall for minimized measurement lag and spatial uncertainty
• Internal recirculation system ensuring homogeneous temperature distribution (<0.02 °C axial/radial gradient) throughout the 10 L working volume
• Refrigeration + heating dual-mode thermoelectric or compressor-assisted system enabling rapid ramping and sub-zero operation down to −5 °C
• LCD interface with dual-display: setpoint vs. actual cavity temperature, plus status indicators for cooling/heating phase and sensor integrity

Sample Compatibility & Compliance

The HT856 accommodates a broad range of infrared sensing devices—including handheld IR thermometers (e.g., Fluke 62 Max+, Testo 805i), fixed-mount radiation sensors (e.g., AMETEK Land Cyclops series), and uncooled microbolometer-based thermal cameras (e.g., FLIR E8, Seek Thermal CompactPRO)—via standardized mounting fixtures and aperture alignment jigs. It supports calibration protocols requiring multiple fixed-point checks (e.g., ice point, 50 °C, 100 °C) or continuous ramp profiling. The device complies with metrological requirements defined in JJG 856–2015 for radiation thermometer verification, including cavity temperature uniformity, emissivity validation, and stray radiation suppression. For quality-critical environments, it supports audit-ready documentation generation aligned with GLP/GMP practices and is compatible with 21 CFR Part 11-compliant software extensions for electronic signature and data integrity.

Software & Data Management

While the HT856 operates autonomously via its onboard controller, optional RS485/USB interface enables integration with third-party calibration management platforms (e.g., MET/CAL, Beamex MC6, or custom LabVIEW-based DAQ systems). Time-synchronized temperature logging at up to 1 Hz resolution, along with metadata tagging (operator ID, UUT serial number, ambient conditions), ensures full traceability. Export formats include CSV and XML, supporting import into LIMS or ERP systems. Firmware updates preserve calibration coefficients and maintain long-term drift compensation profiles—critical for multi-year accreditation cycles.

Applications

• Primary and secondary calibration of infrared thermometers in national metrology institutes and accredited calibration labs
• Performance verification of thermal imaging systems used in predictive maintenance, building diagnostics, and medical thermography
• Validation of emissivity correction algorithms in industrial process control systems
• R&D support for development of next-generation radiometric sensors, including MEMS-based IR detectors
• Educational use in university physics and instrumentation laboratories for teaching radiative heat transfer and temperature metrology fundamentals
• Quality assurance in pharmaceutical manufacturing, where IR-based sterilization monitoring requires documented thermal traceability

FAQ

What is the recommended working fluid for optimal performance across the full temperature range?
Deionized water is suitable from 0 °C to 80 °C; for operation below 0 °C or above 80 °C, low-volatility silicone oil (e.g., Dow Corning 200 Fluid, 50 cSt) is required to ensure thermal stability and prevent cavitation.
Can the HT856 be used for calibration under ISO/IEC 17025 requirements?
Yes—the instrument’s temperature stability, cavity emissivity certification, and traceable Pt100 sensor enable its use as a reference standard in ISO/IEC 17025-accredited laboratories when operated per manufacturer-defined procedures and supported by periodic verification against national standards.
Is external circulation possible with this model?
No—the HT856 is configured exclusively for internal recirculation. External pumping or external bath coupling is not supported due to thermal isolation and safety design constraints.
How often should the blackbody cavity emissivity be re-verified?
Emissivity verification is recommended annually or after any mechanical impact, cleaning with abrasive agents, or exposure to corrosive vapors; certified verification reports are available from authorized metrology service providers.
Does the unit include calibration documentation upon shipment?
Each HT856 ships with a factory calibration certificate (traceable to CNAS-accredited standards), including cavity temperature uniformity map, emissivity test report, and PID tuning parameters—valid for 12 months from date of issue.