PLC (Ladder Logic Diagram)
- 1. FAKULTI KEJURUTERAAN PEMBUATAN SEMESTER I 2017/18 BMFA4223 INDUSTRIAL AUTOMATION Assignment 1 (10% Carry Mark). Name: Sisubalan a/l Selvan Student ID: B051410128 Answer all the questions in this MS Word file, name the file with your Student ID (i.e: B071610530.docx) and submit to Ulearn before the due date. Question 1 A PLC is used to control the sequence in an automatic drilling operation. A human operator loads and clamps a raw workpart into a fixture on the drill press table and presses a start button to initiate the automatic cycle. The drill spindle turns on, feeds down into the part to a certain depth (the depth is determined by limit switch), and then retracts. The fixture then indexes to a second drilling position, and the drill feed-and-retract is repeated. After the second drilling operation, the spindle turns off, and the fixture moves back to the first position. The worker then unloads the finished part and loads another raw part. Let: X1 = spindle up X2 = spindle at desired depth X3 = fixture at position 1 X4 = fixture at position 2 X5 = start button Y1 = spindle on Y2 = spindle down Y3 = fixture to position 2 C1 = drill cycle permit C2 = hole 1 drilled C3 = hole 2 drilled. Construct the ladder logic diagram for the system.
- 3. FAKULTI KEJURUTERAAN PEMBUATAN Question 2 A machine is being designed to wrap boxes of chocolate. The boxes arrive at the ,achine on a conveyor belt. The list below shows the process steps in sequence. i. The box is manually inserted on a conveyor by the operator. ii. The push button START is pressed by the operator and the conveyor (C) starts moving. iii. Process stops operating when the STOP button is momentarily pressed. iv. The box arrives and is detected by an optical sensor (P). After this the conveyor (C) is stopped and the box is clamped in place (H). v. A wrapping mechanism (W) is turned on for 2 seconds. vi. A sticker cylinder (S) is turned on for 1 second to put consumer labelling on the box. vii. The clamp (H) is turned off and the conveyor (C) is turned on. Contruct an Input/Output (I/O) table and develop a ladder diagram for the system. Note: Don’t forget to include the regular start and stop inputs.
- 5. FAKULTI KEJURUTERAAN PEMBUATAN Question 3 The sequence of operation to implement the process illustrated in figure below is to be follows: i. Normally open start and normally closed stop push buttons are used to start and stop the process. ii. When the start button is pressed, solenoid A energizes to start filling the tank. iii. As the tank fills, the empty level sensor switch closes. iv. When the tank is full, the full level sensor switch closes. v. Solenoid A is de-energized. vi. Agitate motor starts automatically and runs for 3 minutes to mix the liquid. vii. When the agitate motor stops, solenoid B is energized to empty the tank. viii. When the tank is completely empty, the empty sensor switch opens to de-energize solenoid B. ix. The start button is pressed to repeat the sequence. Construct and Input/Output (I/O) table and construct the PLC ladder logic diagram for the system.