An automated flow-temperature-humidity control system
GARY O. NELSON, Robert D. Taylor · American Industrial Hygiene Association Journal · 1980
An automated system that controls air flow, temperature, and humidity has been developed from a commercially available temperature=humidity indicator and a specially built flow-temperature-humidity control module. Parameters are set using direct-reading dials on the control module. The air flow is maintained using a mass-flow controller while process controllers connected to the indicator regulate humidity and temperature. The system will run indefinitely without need for operator intervention. If the module and indicator are calibrated properly, accurate air flows (+/- 2% of full scale), temperatures (+/- 0.3 degrees C), and humidities (+/- 2% RH) can be achieved.