ISSN Vol.03,Issue.06, May-2014, Pages:

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1 ISSN Vol.03,Issue.06, May-2014, Pages: KHIN SU HLAING 1, KYAW ZIN LATT 2 1 Electronic Department, Mandalay Technological University, Mandalay, Myanmar, khinsuhlaing235@gmail.com. 2 Electronic Department, Mandalay Technological University, Mandalay, Myanmar, kyawzinlattsbo@gmail.com. Abstract: This paper describes the automatic control of rheometer. Rheometer is a quality control instrument that is used in rubber-related manufacturing industries. Rheometer can measure viscosity and viscoelasticity of fluids, semi-solids and solids. The operation of rheometer is fully controlled by using Programmable Logic Controllers (PLC S) which acts the heart of the system. The system sequence of operation is designed by ladder diagram and the plc programming software. Sensor usually plays its vital part as an input signal transmitter for the plc in the system. By programming the PLC we control the entire system. During this project, sensor has been used to sense the temperature and to control the DC motor. The input signal that has been sent from the sensor to the plc has being made as a reference. Signal in order to determine the output signal that exactly a same with the plc programming language based on the user requirement. The entire system is more flexible and time saving. This developed apparatus is useful not only for testing purpose, but it can be used for research for other types of materials also. Keywords: Rheometer, PLC, Ladder Diagram, Sensor, DC Motor. I. INTRODUCTION Rheometer is a quality control instrument that is used in rubber-related manufacturing industries. The rheometer is used to measure the viscosity of the rubber. The measurement of viscosity must be done in presence of temperature. Today, rubber is finding a wide variety of applications from daily usage to the industrial applications. The field of automation has had a notable impact in a wide range of industries beyond manufacturing. Automation is the use of control systems and information technologies to reduce the need for human work in the production of goods and services. In the scope of industrialization, automation is a step beyond mechanization. Whereas mechanization provides human operators with machinery to assist them with the muscular requirements of work, automation greatly decreases the need for human sensory and mental requirements as well. In order to design a control circuit, it should be divided into several units or modules for its particular task or control which first can be tested or implemented independently and then combined together. The block diagram of PLC Based Rheometer Control System is described in Figure 4.To accomplish the PLC based control system, the design uses four major components: PLC controller, DC motor driver, LM35 sensor and IR sensor. LM35 sensor is used to know the temperature and IR sensor is used to control the DC motor. If the 24Vdc is supplied to the PLC input, the output of PLC shows the ON state of heater the shutter is closed.ir sensor is used to stop the shutter motor. And then the torque motor starts forward to press the sample. If the temperature sensor gets the required temperature, the output of the PLC shows OFF state of the heater and torque motor stops. And then the shutter motor and torque motor start reverse. IR sensor is used to stop the motor. Figure 1 shows the overall block diagram of the system. Programmable Logic Controller DC Motor Drive Circuit DC Motor Drive Circuit LM35 Sensor IR Sensor Fig. 1.Block Diagram of the System. Torque Motor Shutter Motor Heater II. PROGRAMMABLE LOGIC CONTROLLER A. Introduction of PLC PLC is a solid state device. They are well-adapted to a range of automation tasks.all control operations are done using the PLC. The entire bottling process is automated by feeding the necessary conditions into the PLC using ladder logic. Ladder logic is one of the methods of programming a PLC. Thus, depending on the logic developed the various 2014 SEMAR GROUPS TECHNICAL SOCIETY. All rights reserved.

2 KHIN SU HLAING, KYAW ZIN LATT operations take place and the filling and capping of bottles are done. PLC consists of an I/O unit, central processing unit, and a memory unit. The input/output unit of the PLC acts as an interface to the real world. Inputs from real work are given to the input unit which is manipulated based on the programming, and the results are given back to the real world through the output unit of the PLC. All logic and control operations, data transfer and data manipulation operations are done by the central processing unit. The results and statuses are stored in the memory of the PLC. PLC s are used for a wide range of applications especially in the field of control and automation. Figure 2 shows the block diagram of PLC. initial language closely resembles the diagrams used to document the relay logic. By using this approach, the engineers and technicians using the early PLCs did not need retraining to understand the program. To introduce ladder logic programming simple switch circuits are converted to relay logic and then to PLC ladder logic. Any control task modifications are done by changing the program. This is why the use of the PLC is preferred to the traditional hard wired circuits in industrial controls. PLC architecture is shown in figure 3. Fig. 3. PLC Architecture. Fig. 2.Block Diagram of PLC. B. Ladder Programming algorithm There are many types of programming languages in Programmable Logic Controller, PLC. Languages are typically fixed to Ladder Logic (LD), Sequential Function Block (SFC), Function Block Diagram (FBD) and Structure Text (ST). The common program language of PLC is ladder diagram. Programmable Logic Controller (PLC) is a specialized computer used to control industrial machines and processes. PLC has a CPU that is dedicated to run one program that monitors different inputs and logically manipulates the outputs for the desired control. Output/Input signals are DI (Digital Input), AI (Analog Input), PI (Pulse Input), DO (Digital Output), AO (Analog Output) and PO (Pulse Output). There are four basic steps in the operation of all PLCs: which continually take place in a repeating loop: Input Scan, Program Scan, Output Scan and Housekeeping. Thus PLC plays an important role in the feature industry. C.Ladder Logic Ladder diagram is an automatic control diagram language that developed during World War II. Ladder logic is the primary programming language of programmable logic controllers. Since the PLC was developed to replace relay logic control systems, it was only natural that the D. Ladder Softwre Implementation Fig. 4. Auto Station Main Interface. The AutoStation installation package issued by Invt Auto-Control Technology Co., Ltd. (for short, Invt) is an executable program. The main interfaces include 7 sections: Menu, Tool bar, Project Manager Window, Instruction Tree window, Information window, Status bar and Operation area. Figure 4 shows the auto station main interface.

3 III. HARDWARE DESIGN FOR THE SYSTEM This design can be divided into several units or modules. They are sensor unit, processing unit and power unit. There are some devices and components used in the in the design to implement each unit. These devices used in this system are as follows; Power Supply Unit IR Sensor IVC1 1006MAT PLC controller H-bridge DC motor LM35 Temperature Sensor A precision IC temperature sensor Calibrated directly in degree Celsius Sensitivity 10mV/ C 0.5 C accuracy (at +25 C ) Rated for full -55 C to +150 C A. Power Supply Unit The DC power supply unit is vital component in modern electronic devices as they need a wide range of DC voltages for their operations. The purpose of a power supply is to provide the required amount of power specified voltage from primary source. B. IR Sensor In this system, TSOP 1738 IR sensor is used to control the DC motor. The pin diagram of the IR sensor is shown in figure 5. The features of IR sensor are: Photo detector and preamplifier in one package Internal filter for PCM frequency Improved shielding against electrical field disturbance TTL and CMOS compatibility Output active low Low power consumption High immunity against ambient light Fig. 6. LM35 Sensor. D. Features of IVC1 1006MAT PLC Controller The programmable controller PLC that is used in this research is IVC1-1006MAT. It has 10 inputs and 06 outputs. As shown in Figure 7, PORT0 and PORT1 are for Fig. 5. Pin Diagram of IR Sensor. Continuous data transmission possible (1200 bit/s) Suitable burst length. 10 cycles/burst C. LM35 Temperature Sensor LM35 sensor is used to sense the temperature from the heater. LM35 temperature sensor is shown in figure 6. The features of LM35 sensor are; Fig. 7. Structure of IVC1 series basic module. communication. PORT0 is RS232, and use socket Mini DIN8, while PORT1 is RS485 or RS232. The bus socket is for connecting extension modules. The mode selector switch can be set to ON or OFF. E. H-bridge DC Motor Bial control of a DC motor requires a circuit called an H-bridge. The H-bridge, named for its schematic appearance, is able to move current in either through the motor winding. H-bridge topology was chosen

4 KHIN SU HLAING, KYAW ZIN LATT in this system. An H-Bridge configuration using BJTs is shown in Fig 8. It is called an H-Bridge, because it looks like an H letter. An H-bridge is an electronic circuit which enables electric motors to be run forward or backward action. It is available as integrated circuits or can be built from separate components for specific design. In this system, the DC motor with H-bridge driver circuit is used to open and close the shutter and to press the rubber. The motor can provide for both s: clockwise (CW) and counter clockwise (CCW). This circuit uses four transistors for forward and reverse s. Its operation is as follows. To rotate the DC motor four transistors are used. When the transistor Q1 and Q4 are ON and the other transistors are OFF, a positive voltage will be applied across the motor and the motor will rotate clockwise. When the transistor Q2 and Q3 are ON and the other transistors are OFF, the voltage across the motor will be negative, allowing counter clockwise operation of the motor. In DC motor, clockwise for Up-condition and counter clockwise is for Downcondition. Fig. 9. Connection of programming cable. Vcc A Q1 Q3 D M B Q2 Q4 C GND Fig. 8.H-bridge DC-motor Circuit. IV. SIMULATION RESULT OF THE SYSTEM The simulation of rheometer is carried out with the Auto Station in order to know the performance of the controller. AutoStation software platform is used to perform the experiment. The PLC for experiment is equipped withivc1-1006mat programmable logic controller. Figure 9 shows the connection of programming cable and figure 10shows the ladder diagram of the system. Circuit overview of the system is shown in figure 11. In this system, the ladder program must be run in the PLC controller by downloading ladder software. Basic requirements are also needed; PLC Programming Device ( personal computer ) Programming Software and Connector Cable Fig. 10. Ladder Diagram of Rheometer.

5 TABLE 1: LIST OF SYMBOL MEANING FROM LADDER DIAGRAM Input Output X 0 = System Start X 1 = System Stop X 2 = Sensor 1 X 3 = Temperature Sensor X 4 = Sensor 2 Y0 = Heater ON Y1 = Shutter motor forward Y2 = Torque motor forward Y3 = Shutter motor reverse Y4 = Torque motor reverse VII. REFERENCES [1] Carlos A Smith and Armando B Corripio, Principles and Practices of Automatic Process Control, John Wiley & Sons July [2] A.A. Collyer and D.W. Clegg, Rheological Measurement, Second Edition, Chapman and Hall, [3] Krishan Kant, Computer-based Industrial Control, prentice hall of India Pvt.Ltd, [4] W.Bolton, Programmable Logic Controllers, Fourth Edition. [5] International Journal of Mechanical and Production Engineering, ISSN: , Volume-1, Issue- 4, Oct X 5 = Sensor 3 Y5 = LED [6] International Journal of Emerging Technology and Advanced Engineering Website: (ISSN , Volume 2, Issue 8, August 2012). Fig. 11.Circuit Overview of The System. V. SUMMARY The software implementation of the rheometer control system is described. The desired programming software is used in autostation for PLC controller. This system is used in rubber-related manufacturing industries. The rheometer is used to measure the viscosity of the rubber. This machine is very suitable for the industries and laboratory. The IR sensor and LM35 temperature sensor are reliable parts of the system for compared to other. VI. CONCLUSION The operation of rheometer is successfully done with the use of PLC. Utilizing the IR sensors and LM35 sensor, PLC controls the total rheometer. The PLC offers a compromise between advance control techniques and present day technology. The PLC reduces the operator intervention. A rheometer is successfully developed by using PLC. Rheometer can also be used for other types of materials. By this investigation, the quality of rubber/polymer materials such that the product that is produced complies with international standards can be test.