Single-Board-Heater-System/C2/Introduction-to-Single-Board-Heater-System/English

Title of script: Introduction to Single Board Heater System

Author: Rupak Rokade

Keywords: SBHS, block diagram, video tutorial

Visual Clue	Narration
Show slide	Welcome to the spoken tutorial on “Introduction to Single Board Heater System”
Show slide	In this tutorial we will see the Salient features of SBHS Block diagram explanation of SBHS
Show slide	The Single-board Heater System is abbreviated as SBHS It is a micro-controller based lab-in-a-box temperature control setup. The setup has been designed to cater to the needs of undergraduate & postgraduate control courses.
Show slide	It revolves around the concepts of Electronics Serial port communication Micro-controller programming Data acquisition interface Control theory. These concepts serve as the basic foundation for its development.
Show slide	Next we shall talk about the salient features of SBHS. SBHS is a 3000 rupee device with its hardware design and codes released as an open source. However, please note that the actual price during purchase may vary. An open source software is used to interface SBHS. More details can be sought from: sbhs.os-hardware.in
Show slide	It has small time constant of around 1 minute. Hence, one can do realistic experiment in 10 minutes This setup is also available for remote access under Virtual labs project One can access it remotely and get a feel for it. Later the user can buy it or assemble it and set it up as a lab at college or at home.
Show the respective module on the SBHS picture on the slide	Figure shows the picture of Single Board Heater System. It has a SMPS to generate 12 Volt regulated DC power supply.
Show the respective module on the SBHS picture on the slide	A metal blade and a heater coil situated below this metal support.
Show the respective module on the SBHS picture on the slide	A computer fan.
Show the respective module on the SBHS picture on the slide	A display.
Show the respective module on the SBHS picture on the slide	USB and RS232 ports. We would now see the block diagram of SBHS.
Show slide	The figure shows the block diagram of "Single-board Heater System". The SBHS consists of Power Supply 8-bit micro-controller Display Fan Heater Assembly Temperature Sensor Instrumentation amplifier and associated circuitry ISP Serial and USB port We would now see a brief explanation of the various blocks in SBHS.
Show slide	First we will see the Power Supply. The Power supply is basically a 12V 400 watt SMPS. This 12V supply is used directly but most of the circuitry requires 5V supply. Hence separate voltage regulators are used wherever necessary. Also, to avoid any ambiguous temperature readings due to power supply fluctuations, the voltage regulators for System and sensor are kept separate.
Show slide	Next is Micro-controller. An 8-bit ATmega16 micro-controller is used. Micro-controller plays a very important role. It controls every single hardware present on the SBHS, directly or indirectly. It executes various tasks like Setting up communication between computer and SBHS Controlling the amount of current passing through the heater coil Controlling the fan speed Reading the temperature value Displaying parameter values and various other necessary operations.
Show slide	Next comes the Heater and Fan. The heater assembly consist of a metal plate placed about 3.5 mm away from a nichrome wire coil. When current passes through the coil, the coil gets heated. This heat is transfered to the metal plate through convection increasing its temperature.
Show slide	The fan used is a small regular computer fan. It is used for cooling the heated metal plate. Due to some tried and tested reasons, it is placed below the heater.
Show slide	Next comes the Driver block. This is nothing but a device which varies the amount of power delivered to the fan and heater. MOSFETS are used for the same. MOSFETS are operated as per the commands given by the micro-controller. These MOSFET's are actually switched at some PWM frequency.
Show slide	Now we will talk about the Temperature sensor. AD590 is the Temperature sensor used for sensing the temperature of the heated plate. The output of this sensor is in micro ampere per kelvin. The operating temperature ranges from -55 to 150 degree Celsius. Moreover, it does not requires any further process of linearization.
Show slide	Next we will see Instrumentation amplifier. Instrumentation amplifier is used for signal conditioning of the signal generated by AD590. It also provides good input impedance for the temperature sensor Hence, the signal generated by the sensor is not attenuated during signal conditioning.
Show slide	The Display and Indicators block. Display constitutes of a 16x2 LCD display. This means that the display is capable of displaying two lines of 16 characters each. No separate controller is required since it has its own in-built controller. It is used for displaying various parameters like temperature, fan, heater and machine ID (MID) . It is operated in 4-bit mode. The indicators include various on-board LEDs.
Show slide	Next we have Serial Voltage Level Converter block. Used for conversion of signals from serial to TTL and vice versa
Show slide	Next we have USB to Serial Converter block. Used for conversion of signals from USB to serial and vice versa
Show slide	Next we have USB and RS232 port block Used to connect the USB and RS232 cable
Show slide	Last we have the ISP block. ISP stands for "In-System Programming". It is actually a 10 pin male connector. Through this we can program the micro-controller with the help of proper programming device. This brings us to the end of this spoken tutorial on Introduction to Single Board Heater System. Let us summarise what we learnt in this tuttorial
Show slide	In this spoken tutorial we saw the Salient features and Block diagram explanation of SBHSThe various blocks briefly explained include Power Supply Microcontroller Heater and fan Driver Temperature Sensor Instrumentation Amplifier Display USB & RS232 ports ISP
Show slide	# Watch the video available at http://spoken-tutorial.org/What_is_a_Spoken_Tutorial. It summarises the Spoken Tutorial project. If you do not have good bandwidth, you can download and watch it
Show slide	The Spoken Tutorial Project Team Conducts workshops using spoken tutorials. Gives certificates to those who pass an online test For more details, please write to contact@spoken-tutorial.org
Show slide	# Spoken Tutorial Project is a part of the Talk to a Teacher project. It is supported by the National Mission on Education through ICT, MHRD, Government of India More information on this Mission is available at: http://spoken-tutorial.org/NMEICT-Intro Thanks for joining,this is Rupak Rokade from IIT Bombay signing off. Good bye

Contributors and Content Editors

Nancyvarkey, PoojaMoolya, Rupakrokade