Abstract: A system for controlling environmental conditions including irrigation or misting in greenhouses having a plurality of crop beds within one greenhouse enclosure arranged into a plurality of sense zones and a plurality of control zones comprises a plurality of sensors stationed over crop beds within each sense zone comprising an aspirated enclosure and means therein for generating analog electrical signals indicative of web bulb and dry bulb temperatures and also means for generating an analog electrical signal indicative of incident light over the bed of a microcomputer.

Abstract: A system for controlling environmental conditions including irrigation or misting in greenhouses having a plurality of crop beds within one greenhouse enclosure. Aspirated enclosures have associated temperature sensors for measuring dry bulb temperature and humidity, the temperature of a surface over the bed and also a sensor of incident light over the bed. A computer is programmed with a task for inputting temperature data and for calculating the vapor pressure deficit over each bed and for inputting incident light data for measuring a parameter indicative of physiological crop age. A task establishes times for supply of water based upon the gathered data.

Abstract: A system for controlling environmental conditions in greenhouses having a plurality of crop beds. The system comprises sensors stationed over crop beds comprising an aspirated enclosure and means therein for generating analog electrical signals indicative of wet bulb and dry bulb temperatures. The system comprises a microcomputer located within the greenhouse having a central processing unit with associated scratch memory and program memory sections; an analog to digital input section for receiving the analog electrical signals from the sensors; an output section for converting the computer logic signals to electrical signals at power levels to operate electromechanical apparatus; and serial digital pathway means for connecting the central processing unit, input section and output section.