OK Instruments OK-TH-3.0 Three-Zone Temperature and Humidity Environmental Test Chamber

Overview

The OK Instruments OK-TH-3.0 Three-Zone Temperature and Humidity Environmental Test Chamber is an engineered benchtop system designed for precise, repeatable simulation of climatic stress conditions in laboratory and quality assurance environments. Unlike single- or dual-zone chambers, its three-compartment architecture enables independent thermal and hygrometric control across distinct functional zones—typically configured as high-temperature, low-temperature, and ambient/humidity conditioning sections—allowing accelerated thermal cycling, cold-soak-to-humidification transitions, and multi-step environmental profiles without manual sample relocation. The chamber operates on fundamental thermodynamic principles: temperature regulation via a dual-stage, air-cooled refrigeration circuit using R404A and R23 refrigerants; humidity control through steam injection and precision dew-point modulation coupled with desiccant-assisted dehumidification. Its design conforms to the physical constraints and operational logic defined in IEC 60068-2 series standards, supporting both steady-state (e.g., IEC 60068-2-78, GB/T 2423.3) and dynamic test protocols (e.g., IEC 60068-2-30, GB/T 2423.4).

Key Features

• Three-zone independent control architecture enabling simultaneous or sequential execution of temperature ramping, dwell, and humidity conditioning phases
• Benchtop footprint optimized for space-constrained labs, with internal dimensions of 600 × 500 × 400 mm (W×H×D) and full SUS#304 stainless steel construction for corrosion resistance and cleanroom compatibility
• High-fidelity climate control: temperature uniformity ±0.5 °C and humidity uniformity ±2.5 %RH across working volume, validated per IEC 60068-3-5
• Intelligent touch-screen controller with real-time graphing, programmable multi-segment profiles (up to 99 cycles, 999 segments), and built-in data logging (≥30 days at 1-min intervals)
• Dual-refrigerant cooling system (R404A primary stage + R23 cascade stage) ensuring stable operation down to –40 °C with heating rate controllable between 1.0–3.0 °C/min
• Compliance-ready hardware: RS485 Modbus RTU interface, optional Ethernet/IP support, and audit-trail-capable firmware aligned with GLP/GMP documentation requirements

Sample Compatibility & Compliance

The OK-TH-3.0 accommodates a broad range of non-volatile, non-explosive samples—including electronic assemblies, polymer components, medical device packaging, PCBs, and automotive sensors—within its stainless-steel chamber. Its Φ50 mm cable port supports external sensor integration or power feedthrough without compromising seal integrity. All operational parameters meet or exceed the technical requirements of MIL-STD-810G Method 501.6 (High Temperature), Method 502.6 (Low Temperature), and Method 507.5 (Humidity), as well as corresponding Chinese national standards GB/T 2423.1–2423.4 and GJB 150.3–150.4. The system’s control algorithm and sensor calibration traceability are structured to support ISO/IEC 17025-accredited testing laboratories, and its data output format complies with FDA 21 CFR Part 11 when paired with validated software configurations.

Software & Data Management

The embedded controller provides native English/Chinese UI switching, intuitive profile editing, and real-time deviation alarms with configurable thresholds. Optional PC-based OK-EnviroLink software extends functionality with automated report generation (PDF/CSV), remote monitoring via LAN/WAN, user-level access control (admin/operator/guest), and electronic signature capability for 21 CFR Part 11 compliance. Logged data includes timestamped temperature, humidity, setpoint error, compressor status, and alarm history—all stored with SHA-256 hash integrity verification. Data export supports direct import into LIMS platforms and statistical process control (SPC) tools such as Minitab or JMP.

Applications

• Accelerated aging studies of adhesives, conformal coatings, and encapsulation materials under combined thermal-hygrometric stress
• Qualification testing of consumer electronics per JEDEC JESD22-A104 (Temperature Cycling) and A110 (Highly Accelerated Temperature and Humidity Stress Test)
• Stability assessment of pharmaceutical secondary packaging per ICH Q1A(R2) guidelines
• Validation of automotive ECU thermal management performance across extended operating envelopes
• Material coefficient of thermal expansion (CTE) characterization via controlled dimensional metrology within the chamber
• Pre-conditioning of test specimens prior to mechanical or electrical property evaluation (e.g., tensile strength, dielectric breakdown)

FAQ

What standards does the OK-TH-3.0 comply with for environmental testing?
It meets IEC 60068-2-1 (cold), IEC 60068-2-2 (dry heat), IEC 60068-2-30 (cyclic damp heat), GB/T 2423.1–2423.4, and GJB 150.3–150.4.
Can the chamber be customized for larger internal dimensions or extended temperature ranges?
Yes—OK Instruments offers engineering customization for chamber volume, extended low-temperature capability (e.g., –70 °C), and specialized humidity ranges (5–98 %RH) upon request.
Is the controller capable of generating compliant test reports for regulatory submissions?
When used with OK-EnviroLink software and properly validated, it supports ALCOA+ data integrity principles and generates audit-ready reports with electronic signatures.
How is temperature and humidity uniformity verified during factory calibration?
Uniformity is measured using nine calibrated PT100 sensors and capacitive RH probes per IEC 60068-3-5, with results documented in the Certificate of Calibration supplied with each unit.
What maintenance is required to sustain long-term accuracy?
Recommended quarterly inspection of condensate drain lines, annual recalibration of humidity sensors, and biannual verification of refrigerant charge and compressor oil levels per OEM service schedule.