Your Federal Quarterly Tax Payments are due April 15th Get Help Now >>

ECE5320 Assignment_1 by xiuliliaofz

VIEWS: 6 PAGES: 20

									              ECE5320 Mechatronics
Assignment#01: Literature Survey on Sensors and Actuators

          Topic: Electric Heating Elements
                      Prepared by:
                      Kaleb Nelson
     Dept. of Electrical and Computer Engineering
                  Utah State University
   E: kaleb.j.nelson@aggiemail.usu.edu ; T: (435)760-
          7749; F: (435)797-3054 (ECE Dept.)

                        3/6/2009
                                          Slide-2



                                   Outline
       –    Reference list
       –    To probe further
       –    Major applications
       –    Basic working principle illustrated
       –    A typical sample configuration in application
       –    Major specifications
       –    Limitations
       –    And many more relevant issues in applications (such
            as, how to choose, cost information, where to buy
            etc.)

7/25/2011           ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                     Slide-3



                     Reference list
  • http://en.wikipedia.org/wiki/Heating_element (1)
  • http://www.thomasnet.com/products/heating-
    elements-37950805-1.html (2)
  • http://www.watlow.com/products/heaters/index.cf
    m (3)
  • http://en.wikipedia.org/wiki/Joule_heating (4)
  • http://en.wikipedia.org/wiki/Trace_heating (5)
  • http://www.wattco.com/products.html (6)

7/25/2011      ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                    Slide-4

               To explore further
    (survival pointers of web references etc)
  • http://www.thefreedictionary.com/heating+eleme
    nt
  • http://en.wikipedia.org/wiki/Heating_element




7/25/2011     ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                       Slide-5



                 Major applications
  •   Electric range
  •   Space heater
  •   Electric oven
  •   Duct heaters




7/25/2011        ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                       Slide-6



             Major applications cont.
  •   Hair dryers/straighteners
  •   Electric blanket
  •   Toaster oven
  •   Other food industry applications




7/25/2011        ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                      Slide-7



            Major Applications Cont.
  •   Under floor heating
  •   Snow/ice prevention/melting
  •   Frost protection
  •   Frost protection
  •   Anti-condensation




7/25/2011       ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                        Slide-8



            Basic working principle (Ref 4)
  • The main idea behind electric heaters is that when
    you run a current through a conducting material,
    it releases heat.
  • This is sometimes referred to as “Joule heating”
  • This is also sometimes referred to as ohmic or
    resistive heating




7/25/2011         ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                       Slide-9



            Typical sample configuration
  • A heating element can often just be represented
    by a resistor in a circuit.
  • This resistor is connected to a power supply at a
    constant voltage




7/25/2011        ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                     Slide-10



            Typical configuration cont.
  • A typical application circuit is as shown.




7/25/2011       ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                    Slide-11



Kinds of basic heating elements (Ref 1)
  • “Bare Nichrome wire or ribbon”
  • “Screen-printed metal–ceramic tracks deposited
    on ceramic insulated metal (generally steel)
    plates”
  • “Tubular (sealed element): a fine coil of
    Nichrome wire in a ceramic binder, sealed inside
    a tough metal shell”



7/25/2011      ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                       Slide-12



   Kinds of basic heating elements cont.
  • “Heat lamp: a high-powered incandescent lamp
    usually run at less than maximum power to
    radiate mostly infrared instead of visible light.”
  • “PTC ceramic: This material is named for its
    Positive Thermal Coefficient of resistance.”
       – “Becomes extremely resistant above a composition-
         dependent threshold temperature”
       – “Acts as its own thermostat”


7/25/2011         ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                    Slide-13



             Major Specifications
  • Supply voltage
  • Operating temperature
  • Heating element watt density




7/25/2011      ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                     Slide-14



       Types of Heating Elements (Ref 6)
  •   Tubular
  •   Finned tubular
  •   Flange
  •   Boiler
  •   Screwplug
  •   Circulation
  •   Over The Side Immersion
  •   Strip
7/25/2011       ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                       Slide-15



            Types of Heating Elements cont.
  •   Finned strip
  •   Cartridge
  •   Band
  •   Silicone rubber
  •   Open coil
  •   Duct
  •   Infrared radiant


7/25/2011         ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                    Slide-16



                         Limitations
  • Since there are so many types of electric heating
    elements, there are very few limitations that apply
    to all types.




7/25/2011      ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                    Slide-17



                    How to choose
  • PTC Ceramics are good for applications where
    you don’t want to get too hot.
  • High temperature furnaces use materials such as
    platinum, molybdenum disilicide, and silicon
    carbide (1)




7/25/2011      ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                     Slide-18



                 Cost Information
  • The cost information is very variable.
  • This is due to the huge variation in product types.
    Obviously, small tubular heaters are going to be
    cheaper than heating elements for high
    temperature ovens.




7/25/2011       ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                          Slide-19



                            Where to buy
  • There are countless numbers of places to buy
    heating elements.
  • www.Thomasnet.com (product/service) searching
    under “electric heating elements” comes up with
    many different suppliers including:
       –    Wattco.com
       –    Hi-Temp Products Corp.
       –    Accu Therm, Inc.
       –    And many more.

7/25/2011            ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators
                                    Slide-20



              Where to buy cont.
  • If you are looking for a product that uses a
    heating element, you can find countless numbers
    of the previously mentioned applications at
    almost any store.




7/25/2011      ECE5320 Mechatronics. Assignment#1 Survey on sensors and actuators

								
To top