STUDY AND DEVELOPMENT OF HUMIDITY AND TEMPERATURE CONTROL SYSTEM BY USING SMARTPHONES FOR LETTUCE GREENHOUSES

Abstract

This research article aimed at studying and testing the temperature and humidity control performance of a greenhouse fogging system. It used fogging to evaporate water with latent heat and used fans to help dissipate the accumulated heat from the greenhouse. The SONOFF WiFi was used as a module for turning the electrical devices in the greenhouse on and off via a smartphone. A temperature and humidity sensor was used for turning the fogging nozzles on and off to water the lettuce and to monitor the feedback. This is to control the balance of temperature and humidity as desired, which can be operated via a smartphone. A 24 V 6.9 bar high-pressure water pump was installed for water transmission with 4 fogging nozzles of 0.6 millimeters and a 4 inch cross section ventilation fan. Two fan to ventilate the greenhouse. Temperature and humidity results could be were used checked via the eWeLinK application that was connected via WiFi to SONOFF WiFi. Temperature can be controlled in the range of 26 to 31 °C, and the temperature from the outside environment can be reduced by a maximum of 8 °C. The greenhouse could control humidity in the range 70% to 87%. Therefore, the balance of temperature and humidity can be controlled within certain limits. In order to work from smartphone to SONOFF WiFi, there was still a problem of delay response time during some internet interruptions.