Autowave™ - Communications & Power Industries

Communications & Power Industries, Inc.
Beverly Microwave Division
150 Sohier Road
Beverly, MA 01915
Tel: (978)922-6000
Fax: (978)922-8914
Industrial Microwave Heating Systems
Microwave Furnace for Laboratory
and Short Run Production
• Computerized monitor and control via LabVIEW™
• Computerized data-logging (standard)
• Mode-stirring device for more even distribution of
microwave fields in the applicator (standard)
• High Temperature capability of over 1800°C with samples
in a suitably insulated container
• Working volume more than 2,800 cubic inches
• In-depth knowledge of microwave theory is not required
• Available in 3 or 6 Kilowatt models as characterized below
• Available in 2 applicator sizes as characterized below
• Optional vacuum and gas handling systems for process
atmosphere control
• Optional Infrared non-contact temperature measurement
with feedback to control temperature
• Optional computerized process-step sequencing
3 KW microwave power model
6 KW microwave power model
Power Input Voltage
208/Y120 volt
50-60 Hz
208/Y120 volt
50-60 Hz
Power Input Current
20 amps at full microwave power
30 amp main circuit breaker
45 amps at full microwave power
70 amp main circuit breaker
5°C minimum
30°C maximum
5°C minimum
30°C maximum
15 PSI minimum
20-30 PSI recommended
50 PSI maximum
35 PSI minimum
37-45 PSI recommended
50 PSI maximum
50 PSI
50 PSI
1.5 GPM
Cooling Water Heat Load
(at full microwave power)
6 KW maximum
12.5 KW maximum
Ambient Air Temperature (operating)
5°C minimum
35°C maximum
5°C minimum
35°C maximum
1.5 KW maximum
3.5 KW maximum
2.45±0.02 GHz
2.45±0.02 GHz
Forward Microwave Power
3.0 KW minimum
6.0 KW minimum
Applicator Chamber Microwave Power
(waveguide tuned for minimum reflected power)
2.5 KW minimum
5.0 KW minimum
Cooling Water Temperature (source)
Cooling Water Pressure Drop
(differential from inlet to outlet)
Cooling Water maximum applied pressure
Cooling Water Flow
(at recommended pressure differential)
Ambient Air Conditioning Load
(at full microwave power)
Microwave Characteristics
Microwave Frequency
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February 26, 2008
Dimension A (inch)
Dimension B (inch)
Dimension C (inch)
Dimension D (inch)
Dimension E (inch)
Dimension F (inch)
Doorway opening required for installation (inch)
(Table/Desk removed)
System weight (pound)
(without optional features added and without the shipping container and packing
Working volume for object(s) being processed (cubic inch)
(includes any trays, boxes, fixtures, etc.)
Working footprint size for object(s) being processed (inch)
(includes any trays, boxes, fixtures, etc.)
(12 X 20)
(15 X 25)
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February 26, 2008
Standard Features
Mode Stirring Device
The standard mode stirring device is controlled via a switch
that is located on the panel at the desk.
Materials used in the applicator chamber
The applicator door and work-table inside the applicator
chamber are constructed of Aluminum alloy.
applicator side-wall and chamber end that is opposite the
main chamber door is constructed of a non-magnetic
stainless steel alloy.
Water cooling
The side-wall of the applicator chamber and the work-table
inside the chamber are forced-water cooled. In addition,
the magnetron and waveguide isolator are also force-water
cooled. Other system components may also be water
Computer control
National Instruments Corporation's LabView™ software
was used to develop the control software that is used in all
variations of the Autowave™ product line. An executable
version of the control software as well as the source code
that was used to develop the software is included with
each Autowave™ system.
A license for the full
development LabView software package may be
purchased directly from National Instruments Corporation.
A laptop/notebook computer equivalent to the Dell Inspiron
1501 is standard. For interface and control of system
components, the computer is USB connected to a National
Instruments Corporation multi-function DAQ module. The
computer's operating system is Windows©.
Applicator atmosphere
The standard system is configured for processing in
ambient air at ambient pressure. A pressure relief valve on
the applicator chamber will equalize pressure with the
ambient atmosphere when/if the pressure internal to the
chamber exceeds the ambient atmospheric pressure.
Main door seals
There are two seals on the main applicator chamber door.
A Viton® o-ring seal provides a hermetic seal between the
door and the chamber. An RF seal is achieved by using a
Parker Monel mesh-strip with elastomer core in an o-ringlike groove on the door. Both of these seals are field
Waveguide tuning
A hand-operated 3-stub waveguide tuner is standard. The
applicator chamber and working-load contained therein
presents a mismatch for the transfer of microwave energy
from the waveguide into the chamber. When it is used
properly, the 3-stub tuner adjusts the match-conditions so
that the maximum energy can be transferred into the
working load.
Waveguide isolator
A microwave waveguide isolator is used to keep any
reflected energy from returning to magnetron.
magnetron may be damaged by excessive reflected energy
and the isolator protects the magnetron. The isolator is
water cooled and it is capable of absorbing reflected
microwave energy up to the rated power level of the
Autowave™ system.
Vacuum & gas handling (manual)
In the Autowave™ system, the purpose of the optional
vacuum and gas handling sub-system is to provide for a
faster introduction of the working gas to the applicator
chamber. A rotary vane mechanical pump and 3-valves
are provided for that purpose. The pump is capable of
reducing the pressure within the chamber to less than 0.3
millibars. A hand-operated valve controls the connection of
the pump to the chamber. A different hand-operated valve
controls the connection of the regulated working gas to the
chamber. A third hand-operated valve is used for venting
the chamber to the ambient atmosphere. When this
vacuum and gas handling option is specified, a chamber
pressure gauge is provided as a part of the optionpackage.
CPI has experience only with air and dry nitrogen gasses
used for the working atmosphere. It is possible that
alternate gasses may also be used. Regardless of the
type of working gas, the chamber pressure should be
Autowave Products
greater than 1,000 millibars when microwave power is
being injected into the chamber. Care should be taken to
assure that the gas in the applicator chamber does not
become ionized. Ionizing the gas and continuing to keep
the gas ionized will result in braking of the quartz barrier
window at the applicator chamber microwave launching
location. Care should also be exercised to assure that the
gas used will have no possibility of combining with other
materials that may be present that would be capable of
igniting or forming an explosive mixture of materials.
Vacuum & gas handling (automatic)
The three valves described in the manual option are
automated. This option also includes interlocks to assure
that microwave power is applied to the applicator chamber
only when the chamber pressure exceeds 1,000 millibars.
The computer controlled valves will exhaust the chamber
then backfill with the desired gas.
The number of
exhaust/backfill cycles is user-selected. At the conclusion
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February 26, 2008
of the process run, the chamber is vented to the ambient
atmospheric pressure for ease in breaking the hermetic
seal on the main chamber door.
Aluminum applicator chamber
The standard applicator chamber side-wall and chamber
end that is opposite the main chamber door is constructed
of a non-magnetic stainless steel alloy. Selecting this
option will change the chamber side-wall and end that is
opposite the main chamber door to an Aluminum alloy.
The applicator door and work-table inside the applicator
chamber are already constructed of Aluminum alloy.
Infrared (IR) non-contact temperature transducer
The standard Autowave™ system allows the user to input
a microwave power level setpoint to control the forward
microwave power being generated by the magnetron. Due
to many variables within a processing run or from one
processing run to another, the temperature of the object
being processed might vary significantly. This option adds
an IR temperature transducer plus the software that is
used to automatically control the temperature of the object
being processed. There are 2 automatic processing
modes that can be selected by the user when this option
has been included into the Autowave™ system. They are
as follows.
• User enters a setpoint for the desired temperature.
Microwave power is then controlled automatically to
achieve and then maintain the setpoint temperature.
• User enters multiple steps for either power or
temperature setpoints. Microwave power is controlled to
achieve the setpoint value in the duration that is
specified for each step of the process.
Automatic waveguide tuning
As noted above in the standard waveguide tuning
description, there is generally a significant reflection of
microwave energy because of the dynamic microwave
match condition that happens as the working load changes
temperature. In addition, the load itself and positioning of
the load within the applicator chamber may change from
one process run to the next. A fully automatic 3-stub tuner
will counteract load and other variations that cause a
reflection of microwave energy. This assures that the most
microwave power that is available from the magnetron will
be delivered to the working load.
Consistency in
performance from run-to-run with similar working loads is
more easily achieved when this option is selected.
When it is time to scale-up your process
60 KW, 2.45 GHz, NEMA 4X enclosure
120 KW, 2.45 GHz, NEMA 12 enclosure
10 KW, 28 GHz, Laboratory enclosure
Applicator Design tools
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