OK Instruments OK-TH-500.0 Benchtop Temperature and Humidity Controlled Environmental Test Chamber

Overview

The OK Instruments OK-TH-500.0 is a benchtop temperature and humidity controlled environmental test chamber engineered for precision, repeatability, and long-term stability in academic research laboratories. It operates on a dual-loop PID-controlled refrigeration and humidification system, enabling independent regulation of temperature and relative humidity across a wide operational envelope. The chamber utilizes forced-air convection with balanced airflow distribution to ensure uniform thermal and hygric conditions throughout the working volume—critical for material aging studies, electronic component reliability assessment, and biological stability testing. Designed to meet the rigorous demands of university-based teaching, thesis-level research, and third-party service platforms, the OK-TH-500.0 complies with fundamental requirements of ISO 17025-accredited testing environments and supports experimental protocols aligned with ICH Q1A(R3), ASTM D4332, and JEDEC JESD22-A101 standards.

Key Features

• Benchtop footprint (800 × 700 × 500 mm interior) optimized for space-constrained university labs without compromising usable volume (~280 L)
• Air-cooled refrigeration system with environmentally compliant R134a refrigerant; no external water supply or chiller required
• Stainless steel (SUS304) inner chamber and insulated double-wall construction for corrosion resistance and thermal efficiency
• High-resolution 7-inch color touchscreen controller with intuitive graphical interface and multi-segment programmable profiles (up to 99 cycles, 999 steps)
• Real-time data logging via embedded SD card slot and standard Ethernet port; exportable CSV files for traceable analysis
• Comprehensive safety architecture: over-temperature cut-off, humidity sensor fault detection, compressor high-pressure protection, fan failure monitoring, and dry-run prevention for humidifier
• Optional RS485/Modbus RTU interface for integration into centralized lab automation systems or LIMS

Sample Compatibility & Compliance

The OK-TH-500.0 accommodates diverse sample types—including PCB assemblies, polymer films, pharmaceutical dosage forms, seed samples, sensor modules, and small-scale battery cells—within its thermally stable workspace. Its humidity control mechanism employs ultrasonic humidification combined with a stainless steel water reservoir and automatic level detection, minimizing mineral deposition and ensuring consistent RH delivery. For regulated applications, the system supports GLP-compliant operation through user-accessible audit trails, password-protected parameter modification, and time-stamped event logs. While not pre-certified to FDA 21 CFR Part 11, the controller firmware permits configuration of electronic signature workflows and data integrity safeguards compatible with institutional validation protocols.

Software & Data Management

The embedded controller runs OK Instruments’ proprietary ChamberControl™ firmware, offering real-time graphing of temperature/humidity trajectories, deviation alarms with configurable thresholds, and automatic generation of compliance-ready test reports. Data export functionality includes timestamped CSV files with millisecond-resolution sampling intervals (configurable up to 1 Hz). Optional PC-based software (ChamberLink Pro) enables remote supervision via TCP/IP, synchronized multi-chamber coordination, and statistical process monitoring (SPC) overlays for trend analysis. All logged data retain full metadata—including operator ID, chamber serial number, calibration status flags, and environmental ambient readings—ensuring full traceability per ISO/IEC 17025 Clause 7.5.

Applications

• Materials science: Accelerated aging of biodegradable polymers (e.g., PLA, PHA) under cyclic humidity exposure to quantify hydrolytic degradation kinetics
• Electronics reliability: Testing moisture sensitivity levels (MSL) of surface-mount components per J-STD-020; evaluating thermal expansion mismatch in flexible hybrid electronics
• Pharmaceutical research: Conducting ICH-aligned long-term and accelerated stability studies on solid oral dosage forms at 25 °C/60 % RH and 40 °C/75 % RH
• Energy storage: Characterizing electrolyte volatility, separator dimensional stability, and cell swelling behavior in Li-ion batteries under controlled humidity gradients
• Agricultural biotechnology: Simulating regional storage climates for seed viability assays and fungal growth inhibition trials
• Cultural heritage science: Replicating seasonal microclimates to assess hygrothermal stress effects on parchment, wood, and pigment binders

FAQ

What is the maximum allowable sample load for stable humidity control?
For optimal RH stability (<±3 % RH fluctuation), total non-volatile sample mass should not exceed 15 kg. Higher loads may require extended equilibration times and are subject to validation per ASTM E2805.
Does the chamber support unattended operation for 72+ hour tests?
Yes—the system features continuous power-fail recovery, auto-resume programming, and low-water-level alarm with graceful shutdown to prevent heater damage.
Can the internal sensors be externally calibrated?
The PT100 temperature sensor and capacitive RH sensor are field-replaceable and traceably calibratable using NIST-traceable reference instruments; calibration certificates are issued upon request.
Is condensation management addressed during rapid cooling cycles?
An integrated condensate evaporation system actively removes accumulated moisture from the evaporator coil surface, preventing frost buildup and maintaining consistent cooling capacity across repeated thermal transitions.
How is airflow uniformity verified within the working chamber?
OK Instruments provides a factory-generated airflow mapping report (per ISO 16770 Annex B) showing velocity distribution and thermal gradient profiles at nine standardized measurement points across the chamber volume.