YiHeng LHS Series Temperature and Humidity Controlled Chamber
| Brand | YiHeng |
|---|---|
| Origin | Shanghai, China |
| Manufacturer Type | Direct Manufacturer |
| Region Category | Domestic (China) |
| Model | LHS Series |
| Price Range | USD 3,300 – 10,500 (FOB Shanghai) |
| Instrument Type | Vertical Chamber |
| Temperature Range | Type I: −5 to 80°C |
| Type II | −10 to 70°C |
| Humidity Range | Type I: 40–85% RH |
| Type II | 40–95% RH |
| Temperature Uniformity | ±0.5°C (high-temp), ±1.0°C (low-temp) |
| Humidity Deviation | ±3% RH |
| Heating Rate | 1.0–3.0°C/min |
| Internal Chamber Dimensions | See Technical Datasheet |
Overview
The YiHeng LHS Series Temperature and Humidity Controlled Chamber is an engineered environmental test system designed for precise, long-term simulation of controlled climatic conditions in laboratory, quality assurance, and R&D environments. Based on dual-loop PID control architecture with TMHM (Temperature & Humidity Mutual Harmonization) regulation methodology, the chamber maintains stable thermal-hygrometric equilibrium by dynamically coordinating refrigeration capacity, heating output, and steam-based humidification. Unlike single-variable control systems, TMHM prevents overshoot and coupling effects—particularly critical during transitions between low-temperature/high-humidity or high-temperature/low-humidity setpoints. The chamber complies with core operational requirements defined in ISO 17025-accredited laboratories and supports GLP-compliant stability testing per ICH Q1A(R3) guidelines when configured with audit-trail-capable data logging.
Key Features
- Zero-ozone-depleting refrigerant system (R134a or R404A, depending on model variant), fully compliant with Montreal Protocol Phase-Out schedules and EU F-Gas Regulation (EU No. 517/2014).
- Electropolished mirror-finish stainless steel interior (SUS304), featuring radius-rounded corners (R ≥ 15 mm) and adjustable multi-position shelving for optimal airflow distribution and ease of decontamination.
- Dual-sensor humidity control using Vaisala HUMICAP® or equivalent capacitive RH transducers (traceable to NIST standards), calibrated at three points (40%, 60%, and 80% RH) across the operating range.
- Independent over-temperature cut-off circuit with mechanical bimetal switch (non-resettable fuse option available), providing fail-safe protection independent of the main controller.
- Standard 25 mm diameter access port on left side wall, fitted with silicone gasket and brass compression collar—compatible with thermocouple feedthroughs, gas sampling lines, or optical fiber conduits.
- Modular power management architecture: compressors sourced from Embraco (Brazil) or Panasonic (Japan); fan motors rated IP54; condensate evaporation pan integrated into base chassis.
Sample Compatibility & Compliance
The LHS chamber accommodates a broad spectrum of non-hazardous solid and packaged samples—including pharmaceutical primary packaging, polymer films, electronic assemblies, seed viability specimens, and accelerated aging test coupons. Its internal volume (available in 150 L to 1000 L variants) permits uniform exposure under ASTM E145-22 Class II (forced-air circulation) conditions. All models meet EN 60068-2-1 (cold), EN 60068-2-2 (dry heat), and EN 60068-2-78 (damp heat, steady state) test profiles. Optional validation packages include IQ/OQ documentation templates aligned with FDA 21 CFR Part 11 requirements for electronic records and signatures.
Software & Data Management
The standard microprocessor-based controller (YiHeng YC-8000 series) provides real-time display of chamber status, setpoint tracking, and alarm history with timestamped event logging (≥10,000 entries). RS485 Modbus RTU interface enables integration with SCADA platforms or centralized lab monitoring systems (e.g., LabVantage, Thermo Fisher SampleManager). Optional data logger modules support CSV export, configurable sampling intervals (1 s to 60 min), and encrypted local storage on industrial-grade SD cards. When paired with optional thermal printer (Epson TM-T88V), continuous strip-chart recording meets ISO/IEC 17025 clause 7.7 traceability mandates.
Applications
- Stability studies for pharmaceutical products under ICH Q5C and Q1E protocols.
- Accelerated aging tests of adhesives, coatings, and composite laminates per ASTM D3045 and ISO 11341.
- Environmental stress screening (ESS) of printed circuit boards prior to HALT/HASS qualification.
- Seed germination and plant tissue culture preconditioning in agricultural research facilities.
- Calibration verification of portable hygrometers and temperature probes using chamber-as-reference methodology.
- Material compatibility testing of packaging components exposed to tropical or desert climate profiles.
FAQ
What is the typical calibration interval recommended for the humidity sensor?
We recommend annual recalibration against NIST-traceable reference standards, with intermediate verification using saturated salt solutions (e.g., LiCl, MgCl₂, NaCl) every 3 months.
Can the chamber operate continuously at 85% RH and 80°C?
Yes—Type I models are rated for continuous operation at this condition, provided ambient room temperature remains ≤25°C and relative humidity ≤60% to ensure condenser efficiency.
Is remote monitoring supported via Ethernet or Wi-Fi?
Ethernet connectivity is available via optional gateway module (YiHeng NET-100); Wi-Fi is not supported due to RF interference risks with precision analog sensor circuits.
Does the system support user-defined ramp-soak profiles?
Yes—the controller supports up to 24 programmable segments per cycle, including linear ramps, dwell periods, and conditional triggers based on elapsed time or sensor deviation thresholds.
What documentation is included for regulatory submissions?
Factory calibration certificates (with uncertainty budgets), material compliance declarations (RoHS, REACH), and electrical safety reports (IEC 61010-1) are supplied standard; full 21 CFR Part 11 validation kits require separate order.
