3. Preparation

3.1. Task Description

The conveyor band shown below is to be controlled by a Siemens PLC. Inductive sensors (1) are mounted on both sides of the conveyor to detect if a workpiece carrier is there. A retroreflective sensor (2) is used to count how many pillars the workpiece has. Different workpieces will be provided with different number of pillars.

The assignment is as follows: first, the conveyor should be waiting in an idle state. If the sensor at the beginning of the conveyor (i.e., on the left side) detects a workpiece, the conveyor’s motor should be turned on and the workpiece should be transported to the right side. While the workpiece passes the retroreflective sensor in the middle, the number of pillars on the piece should be counted and saved in a variable of type integer.

Fig. 3.1 The conveyor band in question

Fig. 3.2 Workpieces with different pillar counts

3.2. Preparation before the session

Todo

Draw a state machine diagram that describes the software to fulfill the above assignment.

Read through and prepare PLC-Basics and TIA Portal Basics before the lab session.