The Darwin Chambers PH052 is a stability chamber engineered to meet or exceed FDA and ICH requirements for pharmaceutical, cosmetic, and nutraceutical stability testing. It delivers precise environmental control through thermoelectric cooling and ultrasonic humidification, eliminating the temperature uniformity issues inherent in steam boiler systems. The chamber maintains tight control tolerances across its internal volume, supported by redundant cooling circuits and a microprocessor-based PID controller with autotuning and fuzzy logic capabilities.
## Technical Specifications
**Environmental Control**
• Temperature range: 18°C to 50°C
• Temperature control accuracy: ±0.2°C
• Temperature uniformity: ±0.7°C (5-point mapping with corner and center sensors)
• Humidity range: Ambient absolute humidity to 90% RH at 42°C dewpoint
• Humidity control accuracy: ±0.3% RH
• Humidity uniformity: ±2%
• Control resolution: 0.1°C (temperature), 0.1% RH (humidity)
**Sensors & Measurement**
• Temperature sensor: 3-wire PT100 Class A RTD
• Humidity sensor: Rotronic HC2A-S with ±0.8% RH and ±0.1 K accuracy at 23°C ±5 K
**Chamber Construction**
• Interior: 304 stainless steel with matching door liner
• Exterior: Heavy-gauge powder-coated galvanized steel
• Shelving: Two 304 stainless steel shelves
• Door: Positive magnetic seal, self-closing with 120° stay-open feature and lockable handle (two keys included)
• Access port: 2″ ID with foam insert
• Interior lighting: LED with safety shield and door-switch control
**Cooling & Humidification**
• Cooling: Multiple independent thermoelectric units providing inherent redundancy
• Humidification: Ultrasonic system with ¼” poly tube push-to-connect water inlet
**Controller & Integration**
• Microprocessor-based PID with standard Fuji Electric controller
• Functions: Autotuning, fuzzy logic, programmable alarms, calibration correction, ramp/soak, uniformity offset
• Optional touchscreen interface; Watlow and Allen Bradley controllers also supported
**Water Supply Requirements**
• Conductivity: 0.1 µS to 10 µS
• Total dissolved solids: Less than 10 PPM
• Supply pressure: 1–10 PSI
## Typical Applications
Stability testing for drug products, cosmetics, and dietary supplements under regulated GMP conditions.
