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| SK1600-RIC double board - 24 in / 20 out on 13" x 9" mounting plate with power transformer |
Application Article
Customer Utilizes SK1600-RIC in Existing Enclosure for Automatic Valve Control.
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| SK1600-RIC double board - 24 in / 20 out on 13" x 9" mounting plate with power transformer |
Controller used - SK1600-RIC
Total Digital Inputs - 24
Total Digital Outputs - 20
Total Analog I/O - 1 - 4 depending on requirements.
Communication Protocol - No Communications Required
Operator Interface - No Operator Interface Required
The thin film industry works on one basic premise and that is to evacuate a vessel such that the thin film coatings can be applied to substrates with a far decreased risk of contamination. Most coatings contain many layers of material such as Titanium, Nickel, Gold, Quartz, Magnesium Flouride, Etc. These coatings are most often applied in very small amounts (500+ Angstroms). These coatings span many industries with heavy use in the semiconductor and optics industries. For example the Hubble space telescope uses a very large mirror that was made of glass coated with aluminum in a vacuum chamber that was custom built for that single application. Since adhesion to the substrate is most important, the evacuation of the chamber is still one of the most impor tant parts of the process. The evacuation process consists of sequentially operating specialized low and high vacuum pumps through vacuum levels ranging from atmosphere (760 Torr) to roughly the level of vacuum in space (1 x 10-9 Torr). The process takes anywhere from 10 minutes to over an hour depending on the size of the chamber and the capacity and speed of the pumps being used. This process is ultimately complete when the final desired level of vacuum is reached, sometimes as low as (1 x 10-6 Torr). The Yeagle Technology Inc. "Intellitrol Automatic Valve Controller" is a device that provides both manual and automatic sequencing of the valves connected to these pumps to achieve the base pressure required for thin film process execution. One touch automatic functionality provides the user with the ability run perhaps the longest portion of their process without actually being there to facilitate it.
The Intellitrol monitors key pressures throughout the system and controls valves accordingly. It not only guards against improper sequencing but also uses an eloquent system of delays intended to protect pump packages potentially worth tens of thousands of dollars. Additional risk reduction is achieved with automatic functionality since downtime from an improper sequence could potentially amount to a week or more depending on the difference of pressures throughout the system at the time of failure. For high production customers this is the most important feature of this device. It offers three modes of operation. The first is a one-touch control designed to automatically sequence the pump down process. The second allows for manual control of the valve s in a protected fashion as to prevent the user from executing an improper sequence yet allow for a system with performance issues or leaks to still be a viable tool until such a time as repair can take place. The third mode is offered with service in min d and provides unprotected control for every output.
The development of this device was geared towards satisfying a number of specifications. Most important of all was to find a controller that would give the most amount of functionality at the lowest cost. A simple value analysis showed us that using a PLC would fit this application very well. Realistically any PLC fit this application, however we wanted something with a low cost of development and still be able to fit into our desired enclosure. We found that the SK1600RIC from Entertron was a perfect fit for our application on many levels. Not only did it fit into our enclosure similarly to any board we would have developed on our own, but, it also looked like a board we would have developed on our own. This feature definitely added a level of eloquence to our product that we could not have achieved with any other PLC we would have specified. It also supports all of our requirements. Above all it fit within one of our most demanding specifications - an enclosure with a rack mountable panel just 3.5 inches tall. The ultimate requirement for this device is to fulfill all specifications for the lowest cost. The controller itself and the software were what we decided would amount to most of our development budget. Entertron's software is offered free of charge and is very easy to use. We have used some of their other products for some smaller applications and the performance has been incredible. We have had so much success with these products that we plan to move forward with them for both custom control projects and also as volume increases on our main product line.
Information for this article was provided by Steven Pfalzgraf of Yeagle Technology. For more information on Yeagle's capabilities, please visit their web site - http://www.ytionline.com
