Thermo Scientific™ Forma™ Environmental Chambers Available on GSA/VA Contract for Federal Government customers only.

Perform a variety of applications with these environmental chambers, which can be configured for a variety of purposes and are available in multiple capacities.

Manufacturer: Thermo Scientific™ 3940

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Catalog No. 13-067-066

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    Capacity (English) 29 cu. ft.
    Width (English) Interior 31 in.
    Height (Metric) Interior 152.4cm
    Depth (Metric) Interior 68.6cm
    Cabinet Material Cold-rolled steel, powder-coated cabinet
    Voltage 208/220V
    Display Digital dual LED
    Temperature Resolution 0.1°C
    Compressor 1/4hp, air-cooled
    Heat Output 1750W (6000 BTU/hr.) at 220V, 1600W (5500BTUH) at
    Humidity Resolution 0.01
    Humidity Sensor Bulk polymer
    Humidity Source Steam generator; initial fill approx. 1 qt. (1L)
    Water Resistivity 50kilohm to 1megohm resistance
    Lighting Interior Lighting
    Defrost Adjustable defrost timer; factory set for two 15-min. defrost cycles/24 hr.
    Refrigerant CFC-free, R134A
    Width (English) Exterior 38 in.
    Width (Metric) Exterior 96.5cm
    Height (English) Interior 60 in.
    Depth (English) Interior 27 in.
    Width (Metric) Interior 78.7cm
    Capacity (Metric) 821.2L
    Programmability Temperature ramp and soak, up to 24 steps
    Hertz 60Hz
    Temperature Uniformity ±0.3 at 25° to 37°C
    Temperature Sensor RTD
    Temperature Accuracy ±0.1 at 25° to 37°C
    Relative Humidity Relative humidity control via steam generator from above ambient to 95% at 37°C
    Humidity Accuracy ±5.0%
    Humidity Display Digital, dual LED (direct set and read in % RH)
    Height (English) Exterior 88.5 in.
    Certifications/Compliance ICH, FDA, TAPPI, ASTM™
    Capacity 29 cu. ft., 821.2L
    Dimensions (D x W x H) Interior 27 x 31 x 60 in. (68.6 x 78.7 x 152.4cm)
    Electrical Requirements 208/220V 60Hz
    Height (Metric) Exterior 224.8cm
    Depth (Metric) Exterior 81.3cm
    Amperage 15A
    Shelves 6 supplied; 19 max.
    Temperature Range (Metric) 0° to 60°C
    Humidity Control Microprocessor, PID
    Humidity Range Above ambient to 95% at 37°C (98.6°F)
    Input Water Pressure Water Inlet Gravity to 40psi
    Water Consumption 0.25 gal./hr. input water volume
    Depth (English) Exterior 32 in.

    Perform a variety of applications withThermo Scientific™ Forma™ environmental chambers, which can be configured for a variety of purposes and are available in multiple capacities. With a wide range of accessories and years of experience in constructing cabinets, we can construct units to match your most stringent applications.

    Broad Range of Features and Controls:

    • Wide temperature range of 0° to 60°C that enhances the flexibility of the unit
    • Relative humidity control via steam generator from above ambient to 95% at 37°C (not available w/Cat. No. 3920)
    • Sophisticated digital controls
    • Programmable ramp and soak cycles for temperature and RH†
    • Durable cabinets with true laminar airflow through side plenums for extremely tight uniformity
    • Phenolic-coated evaporator for use in applications that create corrosive byproducts
    • Manual control of defrost and refrigeration cycles
    • Visible/audible safety alarms alert to over- and undertemperature conditions, deviation of humidity from set parameters (except Model 3920)

    Durable Construction:

    • Cold-rolled steel, powder-coated cabinet
    • 2 in. (5.1cm) thick, CFC-free, foamed-in-place polyurethane insulation
    • Stainless-steel interior with solid stainless-steel adjustable shelves
    • Directed horizontal airflow system for excellent uniformity
    • Locking swivel casters for easy mobility during installation and cleaning
    • Leveling feet for stability and added safety in the lab

    Broad Range of Options:

    • Interior lighting for Models 3920, 3940 and 3949 (Optional)
    • Reinforced shelving and flooring for heavy loads
    • Heatless dryer for lower humidity levels
    • Access ports for probes, sensors
    • Interior convenience receptacles
    • CO2 (IR sensor)
    • 6 in. and 12 in. temperature chart recorder
    • Other custom options available

    Compatible with:

    • Recorders (197075, 198036, 198039, 198042, 201144, 201145, 201146, 201147)
    • Reach-In/Environmental Chamber Solid Stainless-steel Shelf (224139)
    • Reach-In/Environmental Chamber Perforated Stainless-steel Shelf (224155)
    • Reinforced Stainless-steel Shelf (224161)
    • Fixed Reinforced Stainless-steel Shelf for two shakers (1900005)
    • Stainless-steel Door Glass Cover, factory installed (190591)

    Recommended for:

    Ideal for growth, stability and shelf-life testing applications

    Ordering Information

    † Humidity controller available on 3940/3949, 3911/3913 only


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