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™ 3911

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Catalog No. 13-987-065

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    Depth (Metric) Exterior 81.3cm
    Amperage 15A
    Shelves 3 supplied; 11 max.
    Voltage 208/220V
    Programmability Temperature ramp and soak, up to 24 steps
    Temperature Resolution 0.1°C
    Hertz 60Hz
    Temperature Uniformity ±0.3 at 25° to 37°C
    Temperature Accuracy ±0.1 at 25° to 37°C
    Heat Output 1750W (6000 BTU/hr.) at 220V, 1600W (5500BTUH) at
    Humidity Accuracy ±5.0%
    Humidity Control Microprocessor, PID
    Defrost Adjustable defrost timer; factory set for two 15-min. defrost cycles/24 hr.
    Refrigerant CFC-free, R134A
    Water Consumption 0.25 gal./hr. input water volume
    Capacity 11 cu. ft., 311.5L
    Capacity (English) 11 cu. ft.
    Width (Metric) Exterior 96.5cm
    Height (English) Interior 24 in.
    Width (English) Interior 31 in.
    Width (Metric) Interior 78.7cm
    Cabinet Material Cold-rolled steel, powder-coated cabinet
    Display Digital dual LED
    Temperature Range (Metric) 0° to 60°C
    Compressor 1/4hp, air-cooled
    Relative Humidity Relative humidity control via steam generator from above ambient to 95% at 37°C
    Humidity Display Digital, dual LED (direct set and read in % RH)
    Humidity Source Steam generator; initial fill approx. 1 qt. (1L)
    Water Resistivity 50kilohm to 1megohm resistance
    Height (English) Exterior 51.5 in.
    Width (English) Exterior 38 in.
    Depth (English) Exterior 32 in.
    Height (Metric) Exterior 130.8cm
    Height (Metric) Interior 60.9cm
    Depth (Metric) Interior 68.6cm
    Temperature Sensor RTD
    Humidity Range Above ambient to 95% at 37°C (98.6°F)
    Humidity Resolution 0.01
    Humidity Sensor Bulk polymer
    Input Water Pressure Water Inlet Gravity to 40psi
    Certifications/Compliance ICH, FDA, TAPPI, ASTM™
    Electrical Requirements 208/220V 60Hz
    Depth (English) Interior 27 in.
    Capacity (Metric) 311.5L
    Dimensions (D x W x H) Interior 27 x 31 x 24 in. (68.6 x 78.7 x 60.9cm)

    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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