OKE Rapid Temperature Change Environmental Test Chamber

Overview

The OKE Rapid Temperature Change Environmental Test Chamber is an engineered climatic simulation system designed for accelerated thermal stress testing of electronic components, automotive modules, aerospace subsystems, and industrial control units. It operates on a single-stage vapor-compression refrigeration cycle, optimized for controlled ramp rates between –70 °C and +180 °C (standard operating range; extended ranges available per configuration). The chamber employs a dynamic air circulation architecture with axial-flow centrifugal fans and multi-directional ducting to ensure uniform temperature distribution (±0.5 °C at load, per IEC 60068-3-5). Unlike conventional thermal chambers, this system prioritizes thermal transition fidelity—achieving typical ramp rates of 10 °C/min (–40 °C to +85 °C, empty chamber), validated via NIST-traceable PT100 sensor arrays mounted at ISO-defined test volume corners and center. Its structural integrity conforms to ISO 16750-4 (road vehicles) and MIL-STD-810H Method 502.7 (temperature shock), supporting both steady-state and programmed thermal cycling protocols.

Key Features

• Hermetically sealed Tecumseh-derived single-stage compressor, rated for continuous operation at ambient temperatures up to 35 °C and relative humidity ≤80% RH.
• Finned-tube evaporator with enhanced surface area geometry, delivering 30% higher heat transfer coefficient versus standard smooth-tube designs (per ASHRAE Fundamentals, Ch. 19).
• Brazed plate heat exchanger fabricated from AISI 316L stainless steel, featuring chevron-pattern corrugations, full vacuum-brazed joints, and hydraulic resistance <0.8 bar at nominal flow—reducing system pressure drop and improving refrigerant charge efficiency.
• Import-sourced critical controls: Sanhua (Ranco) solenoid valves (IP67-rated), Castel manual isolation valves (DN10, PN25), and Danfoss liquid line filters (100 µm mesh, desiccant integrated).
• Double-wall insulated construction using 150 mm polyurethane foam (density ≥42 kg/m³, λ ≤0.022 W/m·K), with vacuum-degassed filling to eliminate thermal bridging and moisture ingress.
• Integrated power feedthroughs (up to 30 A, 250 VAC) with thermal cutoff protection, enabling powered-in-test (PIT) configurations where DUTs generate internal heat loads up to 500 W during conditioning.

Sample Compatibility & Compliance

The chamber accommodates test specimens up to 1,000 mm (W) × 1,000 mm (D) × 1,000 mm (H), with customizable interior dimensions and optional internal mounting rails. It supports non-condensing humidity operation (10–95% RH, optional dehumidification module required). All electrical interfaces comply with IEC 61000-6-3 (EMC emission limits) and IEC 61000-6-2 (immunity). Mechanical design adheres to ISO 13849-1 PL e (Category 4) for safety-related control functions. Documentation packages include Factory Acceptance Test (FAT) reports, refrigerant charge logs, and calibration certificates traceable to national metrology institutes (NIM or NPL equivalents). Validated for GLP-compliant validation per IQ/OQ protocols aligned with ASTM E145 and ISO/IEC 17025 requirements.

Software & Data Management

Control is managed via a dedicated 7-inch capacitive touchscreen HMI running embedded Linux OS, supporting programmable profiles with up to 99 segments, 999 cycles, and conditional branching (e.g., dwell-on-reach, deviation-triggered abort). Real-time data logging records temperature, setpoint, compressor status, fan speed, and alarm history at user-selectable intervals (1 s to 60 min). Export formats include CSV and PDF (with digital signature support). Optional Ethernet/Wi-Fi connectivity enables remote monitoring via Modbus TCP or OPC UA, with audit trail functionality meeting FDA 21 CFR Part 11 requirements for electronic records and signatures (when paired with third-party validation-ready SCADA platforms).

Applications

This chamber is routinely deployed in reliability laboratories for thermal shock screening (JEDEC JESD22-A106), solder joint fatigue assessment (IPC-9701), battery cell thermal runaway propagation studies (UL 1642 Annex B), and qualification of avionics enclosures per RTCA DO-160G Section 4. It also serves QC labs performing incoming inspection per AEC-Q200 stress tests and R&D teams conducting accelerated life modeling (Arrhenius-based failure rate estimation). Its rapid transition capability reduces test duration by up to 60% compared to conventional chambers—critical for high-throughput production validation.

FAQ

What are the standard internal dimensions and maximum payload capacity?
Standard models range from 150 L to 1,000 L working volume; payload capacity is determined by thermal mass and airflow constraints—not weight alone. Load calculations require DUT-specific thermal inertia data.

Can the chamber perform humidity-controlled rapid temperature transitions?
Yes—but only when equipped with the optional refrigerant-based dehumidification module and humidity sensor (Vaisala HMP155); dew point control is limited to ≥–40 °C under rapid ramp conditions.

Is the system compliant with MIL-STD-810H Method 502.7?
Yes—the chamber’s thermal transition profile, uniformity, and instrumentation meet all mandatory parameters in Clause 4.2.2 (Test Conditions) and Annex A (Instrumentation Requirements) when operated per documented OQ protocol.

Do you provide IQ/OQ documentation and on-site validation support?
Factory-supplied IQ/OQ templates are included; on-site validation services are available through certified third-party partners accredited to ISO/IEC 17025.

What refrigerant is used, and is it compliant with F-Gas Regulation (EU) No 517/2014?
R-404A is supplied as standard; R-449A retrofit kits are available upon request to meet GWP reduction targets under current EU regulatory timelines.