AAT MEGA II CLEANER, Operating Manual

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9600 Operating Manual Rev. 3.4 10/15/2005 5
2.0 INSTALLATION AND SET UP
2.1 INTRODUCTION
Austin American Technology's Mega® II is a revolutionary new closed-loop,
solvent regenerative, electronic assembly cleaning system with ION detection
and statistical process control capability. This has been made possible by the
development of a new solvent system and associated cleansing ION exchange
resins for solvent purification and reuse. The Mega II cleaner constantly
monitors the resistivity of a special recyclable, non-ozone depleting, non-
flammable, safe organic solvent with outstanding solubility and surface tension
properties. In the Mega II cleaner system, the solvent (Megasolv™ JB) is
recirculated through a unique ion-exchange process in which the soils dissolved
from the electronic assemblies are transferred into an Ion Absorption Chamber
(IAC) and a “cleaned” solvent (free of contamination) is obtained repeatedly for
each cleaning cycle. Megasolv JB was formulated to, and is successful in,
preventing “white residue” which is common when using many other solvent
types such as IPA. The system can also be used with 100% water and mixture of
water and IPA for other cleaning applications.
The process is fully automated and controlled at all times utilizing a
Programmable Logic Controller (PLC), while ionic contamination levels are
monitored by a resistivity controller. By applying the Onsager Theory as it
relates to the conductance of ions in solution, the ionic contamination of each
batch of circuit assemblies is directly obtained by resistivity detection. The
complete cleaning cycle (wash, rinse and dry) is engineered so that it requires
only one process chamber, eliminating the need for additional materials
handling or transferring, and offers an extremely small foot print.
The operator interface is conveniently located and easy to use. Up to five
cleaning profiles with varying time and set point parameters may be stored and
recalled at the push of a button. Maintenance parameters are set by entering a
code number. A two line display indicates status throughout the cleaning
process, as well as alarm and warning conditions. Two RS232 outputs are
available for data transfer and statistical process control software is available in
a Windows format. Data includes wash and rinse cycle time, cleanliness levels,
and chemistry temperature.
The Mega II offers numerous safety features. The process chamber is always
empty when not in use and must be closed and latched before the cleaning cycle
begins. Solvent replenishment is automated; the operator is never in contact
with the solvent during normal operation. At the completion of the cleaning
cycle the process tank drains into the integral holding tank at a controlled rate
(minimizing drag-out); at the completion of the drying cycle the process
chamber is clean, dry, free of solvents and ready for the operator to remove the
cleaned assemblies.