OK Instruments OK-TH-800 Temperature and Humidity Controlled Chamber

Overview

The OK Instruments OK-TH-800 Temperature and Humidity Controlled Chamber is an engineered environmental test system designed for precise, long-term simulation of climatic conditions in laboratory and industrial quality assurance settings. It operates on the principle of closed-loop feedback control, integrating independent refrigeration, heating, humidification, and dehumidification subsystems to maintain stable or programmatically varying temperature and relative humidity (RH) profiles across its internal workspace. The chamber employs a dual-stage air-cooled refrigeration cycle capable of reaching −50 °C, complemented by resistive heating elements for rapid thermal response. Humidification is achieved via a stainless-steel shallow-water tank with electric immersion heaters, while dehumidification relies on condensation-driven moisture removal through the evaporator coil surface — a method aligned with IEC 60068-3-5 and ISO 16750-4 environmental testing methodologies. Its benchtop architecture supports integration into constrained lab spaces without compromising volumetric capacity or field uniformity.

Key Features

• Robust air-cooled refrigeration system with cascade compressor design for reliable low-temperature performance down to −50 °C
• High-stability Pt100 platinum resistance temperature sensors and capacitive RH transducers provide real-time feedback with traceable calibration paths
• Intuitive 7-inch color touchscreen controller with programmable multi-segment profiles (up to 99 cycles, 999 steps), supporting ramp-soak-hold sequences and user-defined dwell times
• Uniform airflow distribution via axial fan array and optimized duct geometry ensures temperature uniformity ≤ ±2 °C and humidity uniformity ≤ ±3 % RH across the full 1000 × 1000 × 800 mm working volume
• Comprehensive safety architecture including over-temperature cutoff, compressor high-pressure protection, water-level monitoring for humidifier, and ground-fault circuit interruption
• Corrosion-resistant interior chamber constructed from electropolished stainless steel (SUS304), minimizing particulate generation and facilitating GMP-compliant cleaning protocols

Sample Compatibility & Compliance

The OK-TH-800 accommodates a broad range of sample types — from printed circuit assemblies and automotive ECUs to polymer specimens, pharmaceutical packaging, and diagnostic reagent kits — without requiring modification to standard mounting fixtures. Its operational envelope satisfies key environmental stress screening requirements defined in JEDEC JESD22-A104 (Temperature Cycling), JESD22-A110 (Highly Accelerated Temperature and Humidity Stress Test), and MIL-STD-810H Method 507.5 (Humidity). While not certified to UL/CSA or CE as a standalone medical device, its construction and control architecture support validation under ISO/IEC 17025-accredited laboratories. All firmware logic adheres to deterministic timing constraints suitable for GLP-regulated stability studies, and data logging meets basic audit-trail expectations for non-21 CFR Part 11 environments.

Software & Data Management

The embedded controller records timestamped temperature and RH values at user-selectable intervals (1 s to 60 min) to internal flash memory (≥1 year at 1-min logging). Export is supported via USB 2.0 to CSV-formatted files compatible with Excel, MATLAB, or LIMS platforms. Optional Ethernet connectivity enables remote monitoring and alarm notification via SMTP or Modbus TCP. Though native software does not implement electronic signatures or full 21 CFR Part 11 compliance (e.g., role-based access control, biometric authentication), raw log files contain immutable metadata — including operator ID input, profile name, start/stop timestamps, and sensor fault flags — enabling manual reconstruction of test integrity for internal QA review.

Applications

• Electronics reliability: Thermal cycling and damp heat testing per IEC 60068-2-14 and IPC-9701 for solder joint fatigue analysis and conformal coating evaluation
• Automotive component validation: Climate endurance testing of infotainment modules, battery management systems, and ADAS sensors under combined thermal/humidity stress
• Materials aging: Accelerated degradation studies of elastomers, adhesives, and composite laminates per ASTM D3045 and ISO 4892-2 (when used in conjunction with UV exposure units)
• Pharmaceutical stability: ICH Q1A(R2)-aligned storage condition simulations (e.g., 25 °C/60 % RH, 30 °C/65 % RH) for bracketing and matrixing protocols
• Food packaging permeability: Moisture vapor transmission rate (MVTR) preconditioning of barrier films prior to gravimetric or infrared analysis

FAQ

What is the recommended water quality for the humidifier?
Distilled or deionized water is required to prevent scale accumulation on the heating element and water level sensor. Tap water or softened water may cause premature failure of the humidification system.
Can the chamber operate continuously at 98% RH below 10°C?
No. Achieving ≥98% RH below 10°C requires extended dwell time and may exceed the system’s dew-point control margin; operation in this regime is not validated and may result in condensation on samples or instrumentation.
Is external ventilation necessary for safe operation?
Yes. The air-cooled condenser requires unobstructed ambient airflow. Install in a room with ambient temperature between 5–28°C and minimum clearance of 50 cm on all sides, especially rear and top surfaces.
How often should sensor calibration be performed?
We recommend annual verification against NIST-traceable references for both temperature and humidity channels. Field calibration using dry-wet bulb comparison or portable hygrometer checks should occur before each critical test campaign.
Does the OK-TH-800 support custom communication protocols for factory automation integration?
The standard Modbus TCP interface allows integration with SCADA and MES systems. Custom protocol development (e.g., OPC UA, MQTT) is available under OEM engineering services agreement.