Description

Conditioning System

Precise air control system ensures conditioned air is distributed uniformly across your product shelves. A stainless steel impeller moves the air through the conditioning components within the enclosed plenum.

Air is then distributed and returned through the plenum’s side wall portswhich are specifically arranged for maximum uniformity and efficientthermal transfer. The conditioning system features include:

• Temperature control to within ±0.2°C
• Relative humidity control to within ±0.7% RH
• Temperature uniformity of ±2.0°C
• Relative humidity uniformity of ±5.0%

Cabinet Construction

Double-wall chamber construction provides you with years of continued, trouble-free use. The interior is heliarc-welded at the seams to form a hermetic seal which prevents moisture from migrating into the insulation.

Each chamber size is proportioned to allow you ease of passage through a standard doorway. Construction features and options include:

• Heavy-gauge stainless steel interior with scratch-resistant enamel on exterior of cabinet.
• Closed-cell urethane insulation for superior high/low temperaturestability and minimal heat transfer. The door is also completely foamedfor thermal performance and rigidity.
• Heavy-duty door hinges, full peripheral magnetic door gaskets andpositive action latch with a lock to maintain a secure, uniform seal.
• Removable stainless steel plenum cover and wall air chases forease in cleaning and maintenance.
• Heavy-duty casters (on floor models) and adjustable levelingfeet for ease in installation.
• Highly reflective specular metal wall coverings on all vertical surfaces.

Proportional Refrigeration System

BES incorporates a proportional liquid/hot gas refrigeration design to maintain close tolerance temperature control and rapid acceleration to your setpoint. The compressor life is extended by modulating refrigerant flow as required. All facets help maintain the life of your chamber under photostability conditions. The proportional refrigeration system features are as follows:

• Air-cooled, hermetically sealed compressor with environmentally safe, non-toxic, CFC-free refrigerants. Optional water-cooled units are available.
• Expansion valve refrigeration control provides higher heat removal capacity than conventional capillary tube designs and provides immediate response to added heat loads.

Lighting System

BES’ upright floor models provide up to (3) simultaneous light studies with adjustable, uniformly-controlled light levels across your product shelves. Intensities are easily and individually controlled at each light bank with a microprocessor-based controller and a photo diode sensor to provide a fully automated, closed-loop control system. The features of each light bank are as follows:

• Automatic adjustment of lamp output to maintain intensities at varied conditions.
• Interchangeable cool white, near-ultraviolet, full spectrum, and dual source cool white/UV banks designed to meet Options 1 and 2 of current ICH/FDA guidelines. Three banks are accommodated in the upright floor model; one bank is provided in the benchtop model.
• Independent light level and timing controls are provided at each individual light bank. Light bank timers provide precise testing durations.
• Individual front reflector panels allow the chamber’s door to open without disturbing tests at other light shelves (floor model only).
• Highly transparent light barrier for maximum transmission of visible and near-ultraviolet light while providing protection for the bulbs.
• Stainless steel light bank shell with specular aluminum interior for corrosion resistance and high reflectivity.
• Shelf-mounted telescoping sensor capable of accurate measurement and control of light levels through varied temperatures, product heights and reflective conditions. Each light surface has a controlling sensor.
• Precision, silicon photo diode light sensor custom-designed by ES and factory calibrated per NIST traceable standards.
• Light level setpoint configuration in kilolux or watts per sq. m. with a digital light level display. Optional units available on request.
• High frequency electronic dimming ballasts offer up to 20% more efficiency than traditional electromagnetic ballasts.

BES control panel features standard high/low visual and audible alarms for temperature, humidity and lighting. The alarms offer you instant visual indication and time-delayed audible indication for quick notification. The temperature and humidity alarms automatically shutdown specific mechanical equipment. The alarm monitoring system features include:

• Alarm silence function on all parameters with up to 60 minutes of delay time (individually adjusted for each parameter).
• Standard N. O./N. C. dry alarm contacts for remote monitoring of each parameter. There is one temperature, one humidity and one general lighting alarm.

Temperature Control System

BES user-friendly microprocessor-based control system incorporates a P.I.D. controller with a subpanel-mounted process board. This board features an L.C.D. backlit display and 4-function membrane switchpad. The system includes digital setpoint and process display of your controlled parameters, while indicator lights monitor power and alarm functions. A non-volatile memory retains your setpoints for restart in the event of a power failure. All controls are mounted on a hinged access panel for ease of maintenance. Features include:

• Temperature display configuration in °C or °F.
• Precision, platinum RTD temperature sensor calibrated per NIST traceable standards.

Upright floor model control panel shown with temperature and humidity control and optional three dual source light bank controls (6 total light systems)

Benchtop model control panel shown with temperature and humidity control,standard dual source light bank controls (2 total light systems) and optional strip chart recorder

Humidity Control System

BES solid-state controlled electric steam humidifier maintains close tolerance humidity control. The humidity system features a direct-set microprocessor control with digital setpoint and process display for your ease of use and readability. High/low humidity capability is dependent on your model selection. See the Humidity Performance Curve sheet for specific ranges on each model. The humidity system includes:

• High output vapor generator with float switch actuated solenoid fill system.
• Dual refrigeration coil design for dehumidification at temperatures depicted on the Humidity Performance Curve sheet.
• Humidity display configuration in % RH.
• Solid-state variable capacitance humidity sensor calibrated per NIST traceable standards.

Product Literature: BES_Photo_Stab_Chmbr