OK Instruments OK-TH-85 Dual 85 Temperature and Humidity Environmental Test Chamber

Overview

The OK Instruments OK-TH-85 Dual 85 Temperature and Humidity Environmental Test Chamber is an engineered solution for accelerated reliability testing under the industry-standard “Dual 85” condition—85 °C and 85 % relative humidity (RH). Designed in accordance with IEC 60068-2-66, IEC 61215, JESD22-A101, and AEC-Q100 test protocols, this benchtop chamber enables precise, long-term stabilization of extreme thermo-hygrometric conditions required for evaluating material degradation, insulation integrity, electrochemical migration, and sealant performance. Its core architecture integrates independent heating, steam-based humidification, and air-cooled refrigeration subsystems—coordinated via a closed-loop PID control system—to maintain thermodynamic equilibrium across the working volume. Unlike general-purpose environmental chambers, the OK-TH-85 is specifically optimized for sustained operation at the critical 85 °C/85 % RH setpoint, where high absolute moisture content demands robust vapor generation capacity, condensate management, and dew-point–based dehumidification logic.

Key Features

• Stainless steel 304 inner chamber with seamless welding and high-temperature silicone door gasket—resistant to oxidation, corrosion, and hydrolytic degradation under continuous 85 °C/85 % RH exposure
• High-efficiency polyurethane insulation (≥100 mm thickness) minimizing thermal bridging and surface temperature rise during extended high-temperature operation
• Dual-mode humidification: boiler-type steam generator for rapid saturation and stable output; integrated water-level monitoring and auto-drain function to prevent scaling and mineral buildup
• Air-cooled refrigeration system with cascade-capable compressor—enabling both active dehumidification (via evaporator subcooling below dew point) and controlled cooling ramping for thermal cycling profiles
• Industrial-grade temperature sensor (PT100 Class A) and capacitive RH sensor (Vaisala HUMICAP®-compatible calibration traceability) mounted on dual-location probe array for spatial uniformity verification
• Programmable controller with ≥100-segment profile capability, real-time trend logging, USB data export, and RS485 Modbus RTU interface for integration into centralized lab monitoring systems
• Comprehensive safety architecture: over-temperature cutoff, dry-run protection for humidifier, refrigerant pressure monitoring, fan failure detection, and ground-fault circuit interruption

Sample Compatibility & Compliance

The OK-TH-85 accommodates PCB assemblies, photovoltaic modules (up to 1.2 m² footprint), automotive ECUs, polymer encapsulants, and coated metallic substrates within its 120 L internal volume (600 × 500 × 400 mm). It meets mechanical and climatic test requirements defined in IEC 60068-3-5 (humidity methods), IEC 61215-2 (photovoltaic qualification), MIL-STD-810H Method 507.6 (high-humidity storage), and GB/T 2423.50 (combined temperature/humidity cycling). All electrical components comply with CE marking directives (EMC 2014/30/EU, LVD 2014/35/EU), and the chamber’s control firmware supports audit-ready data integrity features—including user access levels, electronic signature prompts, and timestamped event logs aligned with GLP/GMP documentation expectations.

Software & Data Management

The embedded controller provides native support for standardized test sequences per IEC 60068-2-30 (damp heat, cyclic) and IEC 61215-2 MQT 10 (damp heat exposure). Optional PC software (OK-EnviroLog v3.2) enables remote supervision, multi-chamber synchronization, automated report generation (PDF/CSV), and deviation alerting via email/SNMP traps. Raw sensor data is recorded at configurable intervals (1–60 s) with metadata tagging (operator ID, test ID, chamber serial number). All logged files include CRC-32 checksums and are write-protected post-acquisition to satisfy FDA 21 CFR Part 11 requirements for electronic records and signatures when operated in validated environments.

Applications

• Photovoltaic module qualification: execution of IEC 61215 damp heat testing (1000 h at 85 °C/85 % RH) to assess delamination, solder bond integrity, and potential-induced degradation (PID)
• Electronics reliability assessment: evaluation of conductive anodic filament (CAF) formation, tin whisker growth, and conformal coating adhesion loss in high-RH bias conditions (JESD22-A101)
• Automotive component validation: thermal-hygric stress screening of ADAS sensors, infotainment displays, and battery management systems per AEC-Q100 Grade 2/3 specifications
• Material science research: accelerated aging of elastomers, adhesives, and composite laminates to quantify hydrolysis kinetics, color shift (ΔE), and tensile property decay
• Quality assurance in medical device manufacturing: stability testing of sterilized packaging under ISO 11607-1 accelerated aging parameters

FAQ

What water quality is required for stable 85% RH operation?
Deionized or distilled water (conductivity < 5 µS/cm) must be used to prevent scale deposition on the steam generator and humidity sensor drift.
Can the chamber perform temperature-humidity cycling per IEC 60068-2-30?
Yes—the controller supports programmable ramps, dwells, and transitions between temperature/humidity setpoints with adjustable rates and hold durations.
Is calibration certification included with shipment?
A factory-as-found calibration report (traceable to NIM, China) is provided; optional UKAS-accredited field calibration services are available upon request.
How is humidity uniformity verified across the working volume?
Uniformity is validated using a 9-point grid per IEC 60068-3-6, with maximum deviation from setpoint limited to ±3% RH at steady state.
What maintenance intervals are recommended for uninterrupted Dual 85 operation?
Monthly inspection of water reservoir, humidifier tank, and condensate drain line; quarterly cleaning of evaporator fins and sensor probes; annual full-system calibration and refrigerant pressure check.