OK Environmental Walk-in Climate Test Chamber OK-STH Series

Overview

The OK Environmental Walk-in Climate Test Chamber OK-STH Series is an engineered large-volume environmental simulation system designed for rigorous thermal and hygrothermal stress testing of industrial components, subsystems, and finished products. Built upon a robust dual-stage refrigeration architecture with cascade compressor technology (utilizing Tecumseh/Tecumseh-derived hermetic compressors), the chamber delivers precise, repeatable control across extreme temperature and humidity conditions. Its operational principle integrates PID-controlled electric heating, steam-based humidification via stainless-steel immersion heaters, and a balanced air circulation system with axial fans and optimized ductwork—ensuring uniform thermal distribution per ISO 16750-4, IEC 60068-3-5, and MIL-STD-810H environmental test method requirements. Unlike benchtop chambers, the OK-STH is specifically structured as a walk-in enclosure, enabling full-scale validation of automotive ECUs, avionics racks, medical imaging systems, server cabinets, and aerospace structural assemblies under real-world climatic exposure protocols.

Key Features

• Modular structural design with double-wall construction: outer panel of pre-painted galvanized steel, inner liner of SUS304 stainless steel, and high-density polyurethane foam insulation (≥100 mm thickness, λ ≤ 0.022 W/m·K)
• Dual-mode refrigeration system: single-stage for standard ranges (−20 °C to +80 °C); optional cascade configuration (−70 °C to +150 °C) using R404A/R23 refrigerant pairs
• High-fidelity climate control: 10.4″ color touchscreen HMI (YX-880 controller) with real-time logging, multi-segment programmability, and alarm history traceability
• Integrated safety architecture: independent overtemperature cutout (mechanical backup), phase failure protection, low-water cutoff for humidifier, ground fault circuit interrupter (GFCI), and door-mounted emergency stop
• Large observation window (tempered double-glazed, anti-fog coated) with internal LED lighting and optional UV-blocking film for optical testing compatibility
• Configurable access: hinged or sliding personnel door with magnetic seal, optional pass-through ports (Φ100–300 mm) with thermal break gaskets and cable management sleeves

Sample Compatibility & Compliance

The OK-STH accommodates specimens up to 50 m³ in volume—including complete vehicle infotainment units, battery modules, HVAC assemblies, and Class III medical devices—without compromising spatial uniformity. All configurations comply with mandatory test standard requirements including GB/T 2423.1–2023 (cold), GB/T 2423.2–2023 (dry heat), GB/T 2423.3–2016 (damp heat, steady state), GB/T 2423.4–2022 (damp heat, cyclic), and GJB 150.3A–2009 / GJB 150.4A–2009. The chamber’s performance validation report includes data on temperature deviation, humidity stability (10–98% RH, ±3% RH tolerance), and ramp linearity—all documented per ISO/IEC 17025-accredited calibration procedures. Optional IQ/OQ documentation packages support GLP and GMP-regulated laboratories seeking FDA 21 CFR Part 11-compliant audit trails.

Software & Data Management

The YX-880 embedded controller supports Ethernet TCP/IP communication (Modbus RTU/TCP), enabling remote monitoring and centralized fleet management via OK’s proprietary LabLink™ software suite. Data export formats include CSV, PDF test reports, and XML metadata compliant with ASTM E2500-22 Annex A3. All logged parameters—chamber setpoints, actual readings, alarm events, and compressor duty cycles—are time-stamped with NTP-synchronized UTC timestamps and stored in non-volatile memory for ≥12 months. Optional 21 CFR Part 11 add-on provides electronic signature enforcement, role-based user access control (admin/operator/auditor tiers), and immutable audit logs with SHA-256 hash verification.

Applications

• Automotive: Validation of ADAS sensor housings, powertrain control units, and EV battery thermal management systems per ISO 16750-4 and LV-124
• Aerospace: Environmental screening of flight-critical avionics per DO-160G Section 4 (temperature), Section 5 (humidity), and Section 6 (altitude simulation interface)
• Electronics manufacturing: Burn-in and HALT/HASS pre-screening of PCBAs, telecom base station enclosures, and 5G mmWave RF modules
• Pharmaceutical packaging: Accelerated stability studies of blister packs and cold-chain shippers under ICH Q1A(R2) and USP conditions
• Academic research: Long-duration climate aging of polymer composites, solar panel encapsulants, and building material prototypes

FAQ

What is the standard lead time for a custom OK-STH chamber?
Typical build-to-order lead time is 12–16 weeks from PO confirmation, inclusive of factory acceptance testing (FAT) and calibration certificate issuance.

Can the chamber be integrated into an existing BMS or MES platform?
Yes—native Modbus TCP and optional OPC UA gateway support enables seamless integration with Siemens Desigo, Honeywell Experion, or Rockwell FactoryTalk environments.

Is on-site installation and commissioning included?
Standard delivery is FOB Guangdong; however, OK-certified field service engineers provide optional SAT (site acceptance testing), operator training, and ISO 17025 traceable calibration at destination.

How is humidity controlled below 0 °C?
Sub-zero humidity operation uses dew-point referencing with chilled mirror hygrometry (Vaisala HMP155), avoiding condensation-related measurement drift during freeze-thaw cycling.

What maintenance intervals are recommended for the refrigeration system?
Compressor oil analysis and refrigerant purity checks every 24 months; filter driers replaced annually; full system leak check and charge verification prior to each annual recalibration.