OK Walk-in Environmental Test Chamber OK-STH-4.8m²

Overview

The OK Walk-in Environmental Test Chamber OK-STH-4.8m² is a large-scale, human-accessible industrial environmental simulation system engineered for precision thermal stress testing under controlled, programmable temperature conditions. Designed in accordance with the functional definition of walk-in chambers per IEC 60068-3-5 and ASTM E1542, it provides a sealed, thermally insulated enclosure capable of generating and maintaining stable temperature profiles across a wide operational range—from cryogenic lows (down to −70°C) to elevated highs (+150°C). Unlike benchtop or upright chambers, this system features an internal volume of 4.8 m³ (1800 mm W × 1500 mm H × 1500 mm D), enabling full-scale evaluation of assembled equipment, vehicle subsystems, energy storage modules, and bulk material lots. Its core measurement principle is closed-loop PID-controlled thermal conditioning via forced-air convection, with real-time feedback from calibrated Pt100 Class A sensors distributed across multiple spatial zones to ensure traceable thermal uniformity.

Key Features

• Modular structural design using high-density polyurethane (PU)-filled insulated panels (100–150 mm thickness) with stainless steel or color-coated steel cladding, ensuring thermal integrity and long-term dimensional stability.
• Dual-stage refrigeration system with scroll or semi-hermetic compressors, copper finned-tube condensers (air- or water-cooled variants available), and expansion valves optimized for low-temperature pull-down performance—particularly critical for −60°C and −70°C configurations.
• High-power nickel-chromium alloy heating elements integrated into the air circulation ductwork, delivering linear, controllable heating rates between 1.0 and 4.0°C/min under no-load conditions.
• Robust air management architecture: heavy-duty centrifugal blower with backward-curved impeller, engineered vertical airflow path (top-down supply, bottom return), and adjustable baffle systems to minimize stratification and achieve ≤ ±3°C uniformity across the working volume per ISO 16750-4 Annex B verification protocols.
• Programmable touchscreen controller compliant with IEC 62443-3-3 cybersecurity baseline; supports up to 999 segments, 99 cycles, and ramp/soak profiles with user-defined dwell times, rate limits, and alarm thresholds.
• Integrated safety layer: independent mechanical over-temperature cutouts, refrigerant pressure switches, door interlock circuits, and ground-fault circuit interrupters (GFCI) aligned with UL 61010-1 and EN 61000-6-2 EMC requirements.

Sample Compatibility & Compliance

The OK-STH-4.8m² accommodates physically large test articles—including electric vehicle battery packs (up to 1.2 m tall × 1.0 m wide), photovoltaic inverters, avionics enclosures, and structural composite panels—without requiring disassembly. Optional penetrations (up to Ø100 mm, configurable quantity/location) support external power feeds, data cabling, and sensor leads while preserving thermal seal integrity. The chamber meets fundamental compliance prerequisites for environmental qualification per MIL-STD-810H Method 501.7 (High Temperature), Method 502.7 (Low Temperature), and Method 503.7 (Temperature Shock), as well as automotive standards including ISO 16750-4, GB/T 2423.1–2023 (cold), and GB/T 2423.2–2023 (dry heat). While not certified to GLP or FDA 21 CFR Part 11 out-of-the-box, its data logging architecture supports audit-ready configuration when paired with optional time-stamped CSV export and password-protected user roles.

Software & Data Management

The embedded controller records temperature setpoints, actual chamber readings, compressor status, heater duty cycle, and alarm events at user-selectable intervals (1 s to 60 min). Raw logs are exportable via USB or Ethernet to standard CSV format for post-processing in MATLAB, Python (Pandas), or statistical analysis platforms. Optional PC-based software (OK-EnviroLog Pro) adds remote monitoring, multi-chamber fleet management, automated report generation (PDF/Excel), and configurable email/SMS alerts. All logged data includes UTC timestamps, operator ID fields, and firmware version metadata—facilitating traceability during internal quality audits or third-party certification reviews. Historical data retention exceeds 30 days at 1-second resolution on internal flash memory, with no cloud dependency or vendor lock-in.

Applications

• Automotive R&D: Thermal cycling validation of ADAS ECUs, traction inverters, and 48V/800V battery systems per LV-124 and VW 80101 specifications.
• Renewable Energy: Accelerated aging studies of grid-tied inverters and lithium-ion battery modules under combined high-humidity-free thermal stress (when paired with optional humidification retrofit).
• Electronics Manufacturing: Burn-in screening and HALT pre-screening of telecom base station hardware, server chassis, and industrial PLCs.
• Aerospace Ground Testing: Functional verification of UAV flight controllers and satellite payload components under simulated stratospheric cold soak (−60°C) and desert operational heat (+70°C).
• Materials Science: Characterization of polymer coefficient of thermal expansion (CTE), metal fatigue initiation under thermal gradient loading, and adhesive bond strength degradation kinetics.

FAQ

What is the standard warranty period for the OK-STH-4.8m²?
The unit carries a 24-month parts-and-labor warranty covering refrigeration, heating, control, and structural components. Compressor coverage extends to 36 months under normal operating conditions.
Can this chamber be upgraded to include humidity control later?
Yes—OK Instruments offers factory-installed or field-retrofittable steam-based humidification systems (±2% RH accuracy, 10–95% RH range) compatible with all OK-STH series chambers. Structural reinforcement and electrical upgrades are included in the retrofit package.
Is external cooling water required for the −70°C configuration?
For continuous operation below −60°C, a water-cooled condenser is strongly recommended. Air-cooled variants are viable only for intermittent use and ambient temperatures ≤ 25°C.
How is temperature uniformity verified and documented?
Uniformity is validated using nine calibrated Pt100 probes placed at standardized locations (center + eight corners) per ISO 16750-4 Annex B. A full verification report—including probe calibration certificates and deviation plots—is provided with each shipment.
Does OK Instruments support custom I/O integration for factory automation systems?
Yes—Modbus TCP and RS-485 interfaces are standard. Optional Profibus DP, EtherNet/IP, and OPC UA drivers are available upon request for MES/SCADA connectivity.