Aplikasi PLC untuk Mengendalikan Pertumbuhan Tanaman Krisan pada Sistem Ebb and Flow

Abstract

Progroninrable Logic Controller (PLC) is a form of controller which can be programmed for various needs. The basic mechanism ($how PLC works is by connecting or disconnecting electric current ofan instrument. lhe objective offhis research is to design and evaluate the performance of PLC in handling Multi Input and Multi Oulput (IMIMO) in floriculture for chrysanthemum. The !LC is given task to activate pump for supplying nutrient solution periodically and to control plant environment according to spec~fied set point. The environmental parameters are acidity and temperarure of nutrient solution, air temperature and humidity inside the greenhouse. lfone of these environmental parameters is above or below the set point, then an appropriate action will he taken nccording to the programmed algorithm in the PLC. Special attention has been paid for controlling the acidity of nutrient solution. Ifthe acidil), of nutrient solrition is 5.257, then it will be corrected by opening the bases solenoid valvefor 75 times until the acidih, increase to 6.01 7, according to the specijied sef point (6.0 - 6.5). lfthe acidify is 6.755, then it will be corrected by opening the acids solenoid valve for 23 times until its acidity decrease to 6.505. Results showed that PLC performed well in controlling the environnrenpt arameters of chwsanthemum grown in ebb andflow system.