Walk-in Environmental Stress Screening Chamber – OK-TH Series

Overview

The OK-TH Series Walk-in Environmental Stress Screening Chamber is an engineered environmental test system designed for accelerated reliability validation of industrial components, electronic assemblies, automotive modules, and aerospace subsystems under controlled temperature and humidity stress conditions. Operating on the principle of forced-air convection with dual-channel PID-regulated refrigeration and steam-based humidification, the chamber delivers precise, repeatable thermal and hygrothermal profiles across its full working volume. It supports static and dynamic environmental stress screening (ESS), burn-in, preconditioning, and long-duration stability testing in accordance with internationally recognized test standards—including GB/T 2423.1 (cold), GB/T 2423.2 (dry heat), GB/T 2423.3 (steady-state damp heat), and GB/T 5170.18 (performance verification of environmental test equipment). The chamber’s structural architecture features double-wall insulated construction with high-density polyurethane foam (≥100 mm thickness), seamless stainless steel inner chamber, and airtight gasketed access door—ensuring thermal integrity, low leakage rates, and minimal energy drift over extended operation cycles.

Key Features

• Modular walk-in design available in five standard internal volumes (100 L to 1000 L), enabling scalable deployment from R&D labs to production QA floors;
• High-efficiency refrigeration system utilizing hermetically sealed compressors (Embraco or Bitzer), eco-friendly R404A/R134a blended refrigerant, and copper-aluminum finned evaporator coils;
• Steam generator-based humidification system with deionized water feed, integrated level sensor, and automatic drain flush cycle to prevent mineral buildup;
• Intelligent LCD touchscreen controller (10.4″ TFT display) supporting bilingual (English/Chinese) interface, multi-segment programmable profiles, real-time curve plotting, and on-screen alarm diagnostics;
• Triple-layer vacuum-coated observation window with embedded low-power fluorescent lighting (Philips TL-D series), eliminating condensation without mechanical wipers;
• Electrical isolation architecture: separate routing of water lines, power distribution, and control signal pathways to eliminate cross-contamination risk and support Class I electrical safety compliance;
• Thermal uniformity validated per GB/T 5170.18–2017: ±1.0°C temperature deviation and ±3.0% RH variation within the 1/10 boundary-defined effective test space.

Sample Compatibility & Compliance

The OK-TH chamber accommodates large-format samples—including server racks, EV battery packs, HVAC control units, and military-grade enclosures—without requiring disassembly or fixture adaptation. Its flat-floor design, reinforced floor loading capacity (≥500 kg/m²), and optional interior lighting and power feed-through ports support in-situ functional monitoring during exposure. All models are factory-verified against GB/T 2423 series standards and fully compatible with ISO/IEC 17025-accredited calibration protocols. While not pre-certified to IEC 60068-2 or MIL-STD-810H out-of-the-box, the chamber’s documented performance envelope and traceable sensor calibration (NIST-traceable Pt100 RTDs and capacitive RH sensors) enable straightforward qualification for those standards via user-conducted test method validation per ASTM E2234 or ISO/IEC 17025 Clause 7.8.

Software & Data Management

The embedded controller provides native data logging at user-selectable intervals (1 s to 60 min), storing up to 10,000 hours of timestamped temperature/humidity/alarms in non-volatile memory. Export is supported via USB 2.0 to CSV or Excel-compatible formats. Optional Ethernet/Wi-Fi connectivity enables remote monitoring through secure HTTP/HTTPS web interface (no cloud dependency). Audit trail functionality includes operator login tracking, parameter change history, and alarm event timestamps—meeting basic GLP/GMP documentation requirements. For regulated environments, third-party software integration (e.g., LabVIEW, MATLAB, or custom SCADA) is supported via Modbus TCP or RS485 protocol.

Applications

• Accelerated life testing of printed circuit board assemblies (PCBAs) and solder joint reliability under thermal cycling and humidity soak;
• Pre-conditioning of lithium-ion battery modules prior to vibration or shock testing per UN 38.3 Section 38.3.4;
• Environmental screening of automotive ECUs per ISO 16750-4 (climatic loads) and AEC-Q200 stress categories;
• Stability assessment of medical device packaging systems (ISO 11607) under accelerated aging conditions;
• Validation of material compatibility (seals, adhesives, conformal coatings) under prolonged high-humidity exposure;
• Qualification of outdoor-rated telecom infrastructure under combined high-temperature/high-humidity stress per Telcordia GR-3108.

FAQ

What is the maximum allowable sample weight inside the chamber?
The floor load rating is 500 kg/m² for all models; actual capacity depends on footprint distribution—consult dimensional drawings for localized support recommendations.
Does the chamber support ramp-soak cycling profiles?
Yes. The controller supports up to 99 segments per program, including linear ramps, dwell periods, and loop functions, with independent setpoint resolution of 0.1°C and 0.1% RH.
Is external calibration certification included?
Factory calibration certificates (traceable to national metrology institutes) are provided with each unit; ISO/IEC 17025-accredited third-party calibration is available as an add-on service.
Can the chamber be integrated into an existing MES or LIMS environment?
Via optional Modbus TCP gateway or OPC UA bridge, raw sensor data and status flags can be streamed to enterprise systems for automated pass/fail decision logic and audit-ready reporting.