Summary of the content on the page No. 1
http://www.LGEservice.com
E-mail:Techsupport@LGEservice.com
MICROWAVE OVEN
SERVICE MANUAL
MODEL : MA-2005ST
CAUTION
BEFORE SERVICING THE UNIT, READ THE
SAFETY PRECAUTIONS IN THIS MANUAL.
Summary of the content on the page No. 2
SAFETY PRECAUTIONS This device is to be serviced only by properly qualified service personnel. Consult the service manual for proper service procedures to assure continued safety operation and for precautions to be taken to avoid possible exposure to excessive microwave energy. PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO AVOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY A) Do not operate or allow the oven to be operated with the door open. B) Make the following safety checks on
Summary of the content on the page No. 3
2-1. Function & Type (1/2) 1. How a Microwave Oven Works The microwave oven is one of the great inventions of the 20th century - millions of homes in world have one. Microwave ovens are popular because they cook food incredibly quickly. They are also extremely efficient in their use of electricity because a microwave oven heats only the food - nothing else. A microwave oven uses microwaves to heat food. Microwaves are radio waves. In the case of microwave ovens, the commonly used radio wave fre
Summary of the content on the page No. 4
2-1. Function & Type (2/2) 2) GRILL COOKING This is a method of cooking with radiant heat from the grill heater on the top of the oven. This is a traditional way of cooking which quickly seals and browns food evenly. The temperature inside the oven is fixed at 180°C, which is ideal grilling temperature for this oven. 3) CONVECTION COOKING This is a method of cooking with hot air from the convection heater situated at the rear of the oven. This method allows food to be browned evenly without losi
Summary of the content on the page No. 5
2-2. Installation & Utensils (1/2) 1. Installation 5. Fill a microwave safe container 1. Unpack your oven and place it on a flat level surface. with 300 ml (1/2 pint) of water. 2. Place your oven in the level location of tour choice with more Place on the GLASS TRAY and than 85cm height but make sure there is at least 30cm of space close the oven door. on the top and 10cm at the rear for proper ventilation. The front of the oven should be at least 8cm from edge of the surface to prevent tipping
Summary of the content on the page No. 6
2-2. Installation & Utensils (2/2) 2.COOKING UTENSILS 3.Plastic dishes, cups, freezer bags, and plastic wraps may be Utensils should be checked to ensure that they are suitable for use used in the microwave oven. Follow the manufacturer’s in the microwave oven. instructions or the information given in the cookbook when The following chart summaries the proper use of cooking utensils using plastics in the microwave oven. in your oven: 4.Metal utensils and utensils with metallic trim should not be
Summary of the content on the page No. 7
3-1. What’s the microwave? (1/2) 1. History of dielectric heating In 1945, Dr. Spencer working for RAYTHEON Co. in the U.S.A found out a pieces of chocolate in his pocket melting suddenly by the electric wave (ultra high frequency wave using for radar) on his experiment for radar. then began research in heating matters by the electric wave. So far, experiments for heating foods by the electric wave has been developed into the household telephone as well as microwave oven, etc. The heating metho
Summary of the content on the page No. 8
3-1. What’s the microwave? (2/2) 3. The safety of microwave oven Since the microwave oven can’t make the native fire like gas, you have no use for worrying about the fire. Because it doesn’t become hot like the ordinary electric range. It has been used in the dinner car of the trains etc. Microwave oven has the shielded structure strictly with metal case not to leak electric wave at once not only using but on opening the door. Because it uses the electric wave, the x-ray is never emitted. The
Summary of the content on the page No. 9
HEAT! HEAT! HEAT! HEAT! HEAT! HEAT! 3-2. Conventional heating vs. dielectric heating 2. Dielectric heating 1. Conventional heating FIRE! 1) The heating is uniform. FIRE! FIRE! 2) The temperature rise is fast (high). 3) If you break the electric power: The microwave oven stops FIRE! HEAT! FIRE! heating at once, so you can’t heat something with the heat WELL-DONE! of their surroundings. FIRE! HALF-DONE! FIRE! 4) Since it heats inside, the surface isn’t damaged. UNDER! WAVE DONE! WAVE WAVE WAVE FI
Summary of the content on the page No. 10
4-1. Construction of microwave oven Cavity Cabinet locking in microwave and holding food. Door Gate coming in and out food. Magnetron It has window Inject microwave and seal to oven. structure OVEN CAVITY PARTS Controller INTERIOR PARTS Control and supervise BASE PLATE PARTS DOOR PARTS operating state of oven. LATCH BOARD PARTS CONTROL PANEL PARTS - 15 -
Summary of the content on the page No. 11
4-2. How does the microwave oven operate? After plugging your oven into a standard household socket, press start button or turn the timer. And then switches (primary, secondary, timer) close the circuit. Eventually the input power will be applied to turntable motor, timer motor, fan motor, oven lamp and high voltage transformer. A high voltage of 2,100 volts AC is generated in the second winging of H.V.Transformer. And the voltage is doubled by H.V.Capacitor & H.V.Diode. The 4Kv DC voltage is
Summary of the content on the page No. 12
4-3. WARNING - High voltage circuit ( 4,000 volt ) * The half-wave voltage doubler circuit consists of the secondary winding of the high voltage transformer, H.V. diode (rectifier), and H.V. capacitor. The H.V. diode allows alternating current (AC) to flow in one direction only and INPUT INPUT - - + + + rectifies it to pulsating direct current (DC). The H.V. capacitor is able to store energy on one half of the AC cycle and release it on the other half cycle. SENONDARY SENONDARY * During the fi
Summary of the content on the page No. 13
4-4. Microwave generation system_Magnetron (1/2) GASKET ANTENNA (OUTPUT) FILAMENT (CATHODE) MAGNET (MAGNETIC CIRCUIT) ANODE MAGNET (FERRITE) VANE FILAMENT TERMINALS FEED THROUGH CAPACITOR FILTER CASE FILTER * The magnetron is the energy source for the microwave oven. ANTENNA The magnetron is a vacuum tube of special construction. ELECTRONS It is basically a diode with addition of a magnetic field. CATHODE It consists of a small, coiled heating element (filament) made of tungsten which readily e
Summary of the content on the page No. 14
4-4. Microwave generation system_Magnetron (2/2) * In order to create an electron flow from cathode to anode, the cathode must be heated and a potential difference must exist between the two. 2,450 MHz. This is accomplished by heating the cathode with 3, 4 to 3,5 V AC. ( from the ANTENNA filament winding of the high voltage transformer) and applying a negative 4000 V DC (from the voltage doubler circuit) to the cathode. ELECTRONS CATHODE * Originally the electrons would travel in a straight lin
Summary of the content on the page No. 15
5-1. Multiwave system What is Multi-Wave The multi-Wave system heats food more evenly than convectional microwave ovens. - 20 -
Summary of the content on the page No. 16
5-2. Infrared sensor What’s the infrared sensor? You may be annoyed when you defrost or reheat food with microwave oven. If you reheat soup, the result is superficial. The surface is hot but inside of the soup is still cold. You have to set the clock and push “Start” again. The cooking time is much longer than you expected. LG microwave oven reduce cooking time. Our revolutionary Infrared sensor makes it 3 times faster than the ordinary microwave. Infrared eye tracks the exact temperature of
Summary of the content on the page No. 17
5-3. Auto moving heater What’s does move automatically? Conventional microwave oven with grill has a heater on the ceiling of cooking room. Whether you cook a pizza or chicken, the position of heater is unmovable. We changed the old way. LG heater is moving when you choose grill, the heater goes down. The angle of heater varies as to each menu. You don’t have to worry about safety. The heater moves back to it’s position automatically after grilling. Your food is more evenly grilled and delici
Summary of the content on the page No. 18
SPECIFICATIONS ITEM DESCRIPTION MA-2005ST MODEL 120 Volts AC 60 Hz Power Requirement 1,550 Watts (13.6 A) Single phase, 3 wire grounded 1,150 Watts full microwave power (IEC705) Power Output 2,450 MHz Microwave Frequency 2M246, 2M248J Magnetron 0 ~ 99 min. 99 sec. Timer 7 9 13 23 /8” (W) x 13 /16” (H) x 18 /16” (D) Outside Dimensions 1 13 5 17 /16” (W) x10 /16” (H) x 18 /16” (D) Cavity Dimensions 42 lbs (approx.) Net Weight 46 lbs (approx.) Shipping weight Touch Control System Control Compleme
Summary of the content on the page No. 19
OPERATING INSTRUCTIONS FEATURES Oven Front Plate Window Door Screen Door Seal Display Window Control Panel Door Open Button Safety Door Lock System Turntable Rotating Ring CONTROL PANEL 1. DISPLAY WINDOW. 2. ONE TOUCH CONTROL: This menu has been pre programmed to cook food automatically by one touch. 1150W 3. AUTO DEFROST: This feature provides you with the best defrosting method for frozen foods. 1 4. CUSTOM COOK: This feature allows you to set and execute a frequently used single stage progra
Summary of the content on the page No. 20
OPERATING SEQUENCE The following is a description of component functions 7. AUTO DEFROST COOKING during oven operation. AUTO NUMBER OF START STOP/CLEAR DEFROST WEIGHT 1. SETTING THE CLOCK 8. CHILD LOCK STOP/CLEAR CLOCK NUMBER CLOCK This oven has a CHILD LOCK feature TO SET CHILD LOCK ex.) To set 4:30, touch number key [4],[3], and [0]. ¥ Touch and hold 0 pad LOCKED appears on NOTE: 1) This is a 12 hour clock. the display. 2) Clock will operate as long as power is applied to the oven. TO
