Publications Details
The automation of the Facility for Atmospheric Corrosion Testing (FACT)
An interactive computerized and automated system to provide environmental control for atmospheric corrosion experiments has been added to the FACT, as well as computerized data acquisition for sample weighing. The FACT allows control of corrosive gas concentrations to simulate industrial atmospheric conditions and requires constant manual adjustment to provide a stable test environment. Because constant manual adjustment is impractical, we have automated this facility to achieve the desired stability. This system incorporates an IBM PC AT using Keithley's Series 500 hardware and Quick500 software development environment to calibrate gas analyzers, and to monitor exposure time, test chamber temperature, and gas concentrations. A second PC has been connected to a Mettler M3 microbalance through an IEEE-488 interface communicating under Lotus Measure. Weighings with a sensitivity of 1 {times} 10{sup {minus}6} gram are transferred directly into a Lotus 123 spreadsheet where the data can then be easily manipulated and plotted. Under computer control, the FACT can now run unattended for more than a week and maintain much better control over gas concentrations (200 {plus minus} 5 ppb and 10 {plus minus} 0.5 ppb for NO{sub 2} and H{sub 2}O and H{sub 2}S, respectively) than was possible with manual control (100 {plus minus} 25 ppb for either gas), after initial stabilization. 9 figs.