DESCRIPTION:
The process setup consists of heating tank fitted with t hyristor-controlled heater for on line heating of the water. Water is supplied from laboratory constant head tank and its flow can be manipulated and measured by provided Rotameter. The temperature of the heated water is sensed by RTD sensor. This measured variable through Temperature Transmitter is communicated to Digital Indicating Controller. Error is calculated and output, accordingly, is communicated to Thyristor Controlled heater to achieve the Set Point. These units along with necessary piping are supported in a well-designed housing and are fixed on base plate. The present set-up is completely computerized controlled. The Digital Indicating Controller have a facility to interface the system with computer which enables to change the PID parameters using computer. The educational software and data-logging package has been developed for unit. This software is compatible to interfacing unit designed by us. This software package provides a comprehensive educational software environment within which the PID investigations can be performed. This software is capable to tabulate the sample readings according to the requirement of experiment under study and results obtained can be compared. The real time data acquisition can be done by interfacing the set-up with computer using software. This software can be used outside the laboratory with the computer to familiarize the students with the equipment and procedures with the help of Flow Diagrams provided in the software. In flow diagrams Set Point, Process Variable and Controllers Output are visible on the screen and this data can be transferred in Excel Files for further calculations, plotting graphs etc. Software allows the user to have control on sampling time, data logging, printing the stored data, preparing spread sheets in Excel etc.
EXPERIMENTATION:
To study the open loop or manual control
To study the proportional control
To study the two mode (P+I) control
To study the two mode (P+D) control
To study the three mode (PID) control
To study the tuning of controller (Open loop method) using Zeigler-Nichols method.
To study the stability of the system using the BODE PLOT.
Auto Tuning
UTILITIES REQUIRED:
Water Supply: 2 LPM.
Electricity supply: 1 Phase, 220 VAC.
Computer: Pentium IV, Windows XP version pre-loaded. One RS 232 Serial communication port free for interfacing unit.
Table for Setup support.
TECHNICAL DETAILS:
Temperature Transmitter Input RTD PT-100 (0-100°C), output 4-20 mA.
Process tank Material Stainless Steel, Capacity 0.5 lit,
Heater Nichrome Wire Heater, Capacity1 kW
Thyristor Controller Input 4-20mA for heater.
Flow Measurement Rotameter.
Piping Size 1/4”
Interfacing unit For input-output communication with auto/manual facility
Micro-processor Controller PID Setting, auto tuning, fully programmable with serial communication
Software For experimentation, PID control, Data logging, trend plot, offline analysis and printing.
Instruction Manual An ENGLISH instruction manual will be provided along with the Apparatus
The whole unit is assembled rigidly on a base plate.
|
