Design and implementation of four level elevator using PLC and VFD

Abstract

designed and implemented. The controller used is a Programmable Logic Controller (PLC) which reads all inputs provided by the system from the different sensors and call buttons inside and outside the cabin and produces accordingly output signals based on a program written in Functional Block Diagram (FBD) language, developed to control the different functionalities of the system. The four level controller is based on the first-come first-served basis, with the exception of priority cases, to reduce energy consumption. The PLC used is a Siemens S7-200 with 24 digital inputs, 16 digital outputs, and an analog input/output expansion module. A Variable Frequency Drive (VFD) is used to drive the AC Motor in both directions, forward and reverse, in a suitable speed to move the elevator cabin between floors in a smooth manner, Altivar 312 from Schneider Electric is the one used.