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Room Construction
Rooms are constructed of
prefabricated metal tongue and groove sectional panels. An
assembled room has continuous steel perimeters to hold
panels tightly in place.
Panel features include:
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100% insulation
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Light weight for easy handling – average
weight of the largest panel is 84 lbs.
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Alignment pins for accurate fit.
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Steel straps connect locking arms with
locking pins on opposite sides of panels.
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Cam-actuated locks ensure tight fits and
accommodate frequent assembly/disassembly for relocating
or enlarging the room.
Viewing Windows
The standard multipane window has a 14" by 23" viewing area.
Thermostatically controlled heater wire in the window casing
minimizes condensation and frost formation on the window
surface. Custom size windows are available.
Lighting
All lighting fixtures are vapor
proof and sealed. Both incandescent and fluorescent lighting
fixtures are available.
Incandescent lighting is recommended for high temperature
units operating above +110°F and low temperature units
operating below 0°F.
Forced Air Circulation Systems
All rooms incorporate forced air circulation. Differences in
the size of the chamber and its internal configuration are
accommodated by various airflow patterns, including
horizontal, vertical, or a combination of both. These
provide an even distribution of air and tight temperature
control. Noise is also a consideration.
The air circulation systems use external
heavy duty motors to distribute air evenly and constantly
recirculate it, maintaining uniform and accurate
temperatures and humidity. The high quality motors have
internal cooling fans, protectors, and stainless steel
shafts. Aluminum or stainless steel squirrel cage blowers
circulate the air. All mixing is within a plenum that is
external to the room work area.
In tight tolerance environmental rooms, air
must be evenly distributed and constantly recirculated at a
higher than normal rate in order to maintain uniformity and
accuracy. A portion of one wall of the room is devoted to a
conditioning plenum. Air is drawn into the lower part of the
plenum through a set of cleanable filters, across an
evaporator coil and vertically across electric heaters. The
air then enters centrifugal fans and is discharged into a
perforated ceiling plenum. The air flows vertically downward
in the room and is returned horizontally through the
cleanable filters to the wall plenum.
Electric Heating System
The combination of airflow, instrument response, and
fast-reacting heaters provides very accurate and straight
line control of temperatures.
Air is passed over the fast response, low
watt density heaters with ceramic cores. This type of system
provides very accurate air and humidity control. A separate
instrument precisely controls the heat level.
The heating systems have a long life and are
very reliable, with no down time.
Instrumentation
Instrumentation consists of either
single or two-channel microprocessor programmers with an
accuracy of ±.25°C or better at the sensor. The sensors are
fast acting 100 Ohm. platinum type.
Other options include: RS-232, IEEE-488
interface.
Safety
Standard is a redundant control circuit with its own
controller and failsafe contactor. To prevent thermal
runaway, the safety control shuts off power to the heater
circuit and the circulation blowers continue to distribute
heat within the room. This feature is particularly important
if there are heat-generating items in the room. When the
temperature goes down, the safety control closes and power
is restored to the heaters.
Other available safety options are: High
Temperature Safety with Complete Shut Down of Room with
Manual Reset and Visual Indication, Low Temperature Safety
with Complete Shut Down of Room with Manual Reset and Visual
Indication, Both High and Low Temperature Safety with Manual
Reset on Both and Visual Indication, Audible Alarm, and
Remote Station Alarms.
Electrical Requirements
Standard power requirements
include 208V 3PH 60HZ, 220/240V 3PH 60HZ, 460V 3PH 60HZ,
208/220V 1PH 60HZ. Other power requirements are available
upon request.
Temperature Ranges
Various ranges can be provided,
including fast change rates with your product load. Ranges
from -73°C (-100°F) to +85°C are available.

Humidity
Standard ranges available
are: 20% to 95% ±5% RH. 10% to 98% ±2% RH. Different ranges
available including special dehumidity ranges to 5% RH.
Humidity System
Two Humidity systems are
standard:
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Fine Mist System is recommended when
doing continuous testing with high live loads.
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Steam Generator System is recommended for
rooms being used for low and high humidity testing
within the range of +40°F to +130°F.
The conditioned Fine Mist System uses your
local water supply. Steam is created within a plenum outside
the room area by spraying a fine mist over a stainless steel
sheath-type heater. The circulation system carries this
steam throughout the room.
The Steam Generator System uses an external
self-contained steam generator with all necessary safety and
water level controls to provide humidities to saturation
point within the room.

Refrigeration Systems
AES supplies a refrigeration package that supports the load
demands of the Walk-In Environmental Room.
All systems:
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Operate continuously in cooling mode.
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Provide a hot gas by-pass system to
automate capacity reduction when the room is at the set
point temperature.
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Are constructed with high quality
components including: liquid line solenoids, liquid
sight glass, dryers, strainers, and TX valves.
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Contain Copeland semihermetic (or equal)
compressors.
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Contain Penn (or equal) controls.
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Comply with ASHRAE guidelines for piping
and rating.
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Are factory-assembled and tested.
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Are simple to maintain because components
are easily accessible and clearly labeled.
Up to 5 HP units can be mounted on the roof
of the room. Larger units are installed on the floor next to
the room.
Comprehensive piping diagrams, schematics,
and charging data are available. |