Environment Temperature Control Using Modbus and Rs485 Communication Standards
Environment Temperature Control Using Modbus and RS485 Communication Standards
Abstract – This paper reports an undergraduate engineering team’s effort to develop a system which emulates a curing process chamber found in many industry settings. Based on industry utilization of bus protocols, it has been determined that the de facto standard Modbus protocol under the industry recommended standard interface RS485 is an appropriate communication method for this closed-loop control system. This paper will outline and discuss the implementation of these standards within this system and will also explain the differences between an established and de-facto standard and why this is important when deciding which protocols should be implemented for a particular project.
INTRODUCTION
The Engineering Technology and Industrial Distribution Department at Texas A&M University is pursuing an initiative to integrate curriculum from Electronics Engineering Technology, Mechanical and Manufacturing Engineering Technology and Nuclear Engineering to create a Power Engineering Technology program. In addition to developing new courses for this path of study, existing courses are being redeveloped. In the Electronics Engineering Technology Program, the Instrumentation and Control Systems course is being restructured to focus on a systems-level development process. In the power industry, master and multi-slave control over a standardized architecture is a prime example of changes in the program. A team enrolled in the Instrumentation and Control Systems course has undertaken a project to develop a system which will be used to facilitate the laboratory requirement for this course. This project will also provide a reference design for future students learning similar communication systems.
SYSTEM OVERVIEW
The temperature control system, depicted in Figure 1, emulates a curing process chamber found in many industry settings. The system reads the temperature of the chamber and adjusts it
Abstract – This paper reports an undergraduate engineering team’s effort to develop a system which emulates a curing process chamber found in many industry settings. Based on industry utilization of bus protocols, it has been determined that the de facto standard Modbus protocol under the industry recommended standard interface RS485 is an appropriate communication method for this closed-loop control system. This paper will outline and discuss the implementation of these standards within this system and will also explain the differences between an established and de-facto standard and why this is important when deciding which protocols should be implemented for a particular project.
INTRODUCTION
The Engineering Technology and Industrial Distribution Department at Texas A&M University is pursuing an initiative to integrate curriculum from Electronics Engineering Technology, Mechanical and Manufacturing Engineering Technology and Nuclear Engineering to create a Power Engineering Technology program. In addition to developing new courses for this path of study, existing courses are being redeveloped. In the Electronics Engineering Technology Program, the Instrumentation and Control Systems course is being restructured to focus on a systems-level development process. In the power industry, master and multi-slave control over a standardized architecture is a prime example of changes in the program. A team enrolled in the Instrumentation and Control Systems course has undertaken a project to develop a system which will be used to facilitate the laboratory requirement for this course. This project will also provide a reference design for future students learning similar communication systems.
SYSTEM OVERVIEW
The temperature control system, depicted in Figure 1, emulates a curing process chamber found in many industry settings. The system reads the temperature of the chamber and adjusts it
References: [1] http://en.wikipedia.org/wiki/De_facto_standard [2] http://www.iso.org/iso/home.htm [3] http://www.simplymodbus.ca/ [4] http://www.simplymodbus.ca/ASCII.htm [5] http://www.lammertbies.nl/comm/info/RS-485.html [6] http://www.wut.de/kpics/e-6wwww-13-grus-000.gif