OK Walk-in Constant Temperature & Humidity Chamber OK-STH-8.3m²

Overview

The OK Walk-in Constant Temperature & Humidity Chamber OK-STH-8.3m² is a fully engineered environmental test system designed for system-level reliability validation under controlled thermal and hygrothermal conditions. Unlike benchtop or upright chambers, this walk-in chamber features an internal usable volume of 8.3 m³ (2000 mm × 2000 mm × 2000 mm), enabling direct human access for instrumenting, interconnecting, and monitoring large-scale test articles—including complete electric vehicles, battery energy storage systems (BESS), avionics racks, photovoltaic inverters, and telecom server cabinets. Its operational principle relies on dual-stage refrigeration (cascade compression cycle), precision PID-controlled steam humidification, and high-volume laminar air distribution—ensuring traceable, repeatable, and spatially uniform environmental profiles across the entire working volume. The chamber complies with fundamental requirements of ISO 16750-4 (road vehicles), IEC 60068-2 (environmental testing), and MIL-STD-810G Method 502.6 (low temperature) and Method 507.5 (humidity), serving as a foundational infrastructure for GLP-compliant qualification testing in regulated industrial sectors.

Key Features

• Structural integrity: 150 mm thick insulated sandwich panels with double-skin galvanized steel cladding and high-density polyurethane (PU) core (λ ≤ 0.022 W/m·K), assembled via modular cam-lock joints for field scalability and maintenance accessibility.
• Reinforced load-bearing steel frame with anti-vibration base mount, supporting static loads up to 1,200 kg distributed across the floor plate.
• Hermetically sealed walk-in door with triple-layer low-E tempered glass viewport, electrically heated anti-fog film, mechanical safety lock, and automatic door seal pressure compensation.
• Cascade refrigeration system comprising separate high-temperature (R404A) and low-temperature (R23) compressor stages, delivering stable operation down to −70°C with integrated oil management and hot-gas defrost logic.
• Steam-based humidification system with deionized water feed, stainless-steel evaporator, and condensate recovery loop—capable of maintaining 20–98% RH at temperatures ≥ +10°C.
• Redundant safety architecture: independent high-limit temperature cutoffs (mechanical and electronic), refrigerant high-pressure cutout, door-open alarm, and emergency power-off (EPO) interface compliant with IEC 60204-1.

Sample Compatibility & Compliance

The OK-STH-8.3m² accommodates physically integrated test objects exceeding 1,800 mm in any dimension, including full-size EV battery modules (up to 2,000 mm × 1,500 mm × 250 mm), outdoor-rated DC fast chargers, and 19-inch rack-mounted 5G baseband units. Optional through-wall ports (Φ60 mm, IP65-rated) support thermocouple, current/voltage, CAN bus, and fiber-optic signal penetration without compromising chamber integrity. All control firmware and data logging functions adhere to FDA 21 CFR Part 11 requirements for audit trail, electronic signature, and data integrity—validated per IQ/OQ protocols. Calibration certificates are traceable to NIM (National Institute of Metrology, China) and include as-found/as-left verification at three spatial points (center, upper corner, lower corner) per ISO/IEC 17025.

Software & Data Management

The chamber integrates a CE-certified PLC-based controller with a 10.1″ capacitive touchscreen HMI running OK-EnviroControl™ v4.2 firmware. Users define multi-segment temperature/humidity profiles with ramp/soak logic, real-time deviation alarms, and conditional branching (e.g., “hold until internal dew point reaches −40°C”). Data acquisition records up to 32 analog channels (including external sensor inputs) at 1 Hz resolution, stored locally on encrypted SD card and simultaneously streamed via Modbus TCP or OPC UA to enterprise MES/LIMS platforms. Built-in report engine generates PDF test summaries with embedded trend plots, statistical summaries (mean, std dev, min/max), and digital signatures—fully compliant with ISO 9001:2015 clause 8.5.2 (preservation of documented information).

Applications

• Automotive: Cold-start validation of BEV powertrains at −40°C; HVAC performance mapping across humidity gradients; thermal runaway propagation studies in 48V/800V battery packs.
• Aerospace: Environmental stress screening (ESS) of UAV flight control systems per DO-160G Section 4 (temperature) and Section 10 (humidity); ground-support equipment thermal soak testing.
• Energy Storage: UL 9540A-compliant cell-to-pack thermal propagation tests; calendar life assessment of LiFePO₄ BESS under 40°C/95% RH accelerated aging.
• Telecom Infrastructure: Thermal management validation of O-RAN radios under combined high-temperature/high-humidity conditions per ETSI EN 300 019-1-3 Class 3.2.
• Industrial Electronics: Burn-in qualification of industrial PLCs and motor drives per IEC 60721-3-3 Class 3K5, including 168-hour continuous operation at 85°C/85% RH.

FAQ

What is the maximum allowable heat load from DUTs during operation?
The chamber’s cooling capacity is rated for up to 5 kW continuous internal heat dissipation at −40°C ambient. For higher loads (e.g., powered battery testing), optional liquid-cooled condenser retrofit or external chiller integration is available.
Can the chamber be validated for GMP/GLP compliance?
Yes—full IQ/OQ documentation packages, including sensor calibration maps, alarm response verification, and software configuration audit reports, are provided upon request and align with Annex 15 and WHO TRS 996 requirements.
Is remote monitoring supported over corporate networks?
Standard Ethernet (RJ45) and optional 4G LTE modem enable secure HTTPS-based remote viewing of live parameters, historical trends, and alarm logs via browser or OK-EnviroView™ mobile app.
How is humidity controlled below 0°C?
Humidity control is disabled below +10°C per IEC 60068-3-5. Sub-zero testing operates in dry-cold mode only; frost formation on sensors and surfaces is mitigated by periodic hot-gas defrost cycles synchronized with temperature stabilization phases.
What electrical supply is required for installation?
Three-phase 380 VAC ±10%, 50 Hz, 63 A dedicated circuit with TN-S earthing is mandatory. Voltage imbalance must not exceed 2% between phases.