Lg Des11ea Service Manual

Microwave Oven

Service Manual

DECS11MA DES11EA DFS11G DFS11EA UCS11MA US11EA UFS11EA

CAUTION BEFORE SERVICING THE UNIT, READ THE SAFETY PRECAUTIONS IN THIS MANUAL.

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 all ovens to be serviced before activating the magnetron or other

microwave source, and make repairs as necessary; (1) interlock operation, (2) proper door closing, (3) seal and sealing surfaces (arcing, wear, and other damage), (4) damage to or loosening of hinges and latches, (5) evidence of dropping or abuse.

C) Before turning on microwave power for any service test or inspection within the microwave generating

compartments, check the magnetron, wave guide or transmission line, and cavity for proper alignment, integrity, and connections.

D) Any defective or misadjusted components in the interlock, monitor, door seal, and microwave generation

and transmission systems shall be repaired, replaced, or adjusted by procedures described in this manual before the oven is released to the owner.

E) A microwave leakage check to verify compliance with the Federal Performance Standard should be

performed on each oven prior to release to the owner.

SAFETY PRECAUTIONS

(Page)

SAFETY PRECAUTIONS

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Inside front cover

SPECIFICATIONS

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1-1

CAUTIONS

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2-1

INSTALLATIONS

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3-1

OPERATING INSTRUCTIONS

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4-1

COOKING DISPLAYS

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4-5

PROGRAMMING DISPLAYS

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4-5

OPERATION

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4-6

PROGRAMMING

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4-7

SCHEMATIC DIAGRAM

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4-9

CIRCUIT DESCRIPTION

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4-10

SERVICE INFORMATION

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5-1

TOOLS AND MEASURING INSTRUMENTS

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5-1

MICROWAVE LEAKAGE TEST

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5-1

MEASUREMENT OF MICROWAVE POWER OUTPUT

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5-3

DISASSEMBLY AND ADJUSTMENT

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5-3

INTERLOCK CONTINUITY TEST

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5-7

COMPONENT TEST PROCEDURE

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5-8

TROUBLE SHOOTING

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5-11

EXPLODED VIEW

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6-1

SCHEMATIC DIAGRAM OF P.C.B.

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7-1

PRINTED CIRCUIT BOARD

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7-2

CONTENTS

1-1

SPECIFICATIONS

This microwave oven is designed for commercial use only. It is not recommended for built-in installation.

ITEM

MODEL

Power Requirement

Power Output Microwave Frequency Magnetron Timer Outside Dimensions Cavity Dimensions Net Weight Shipping weight Control Complement

Nameplate Location

DESCRIPTION

230 Volts AC 50 Hz 1,600 Watts Single phase, 3 wire grounded 1,100 Watts full microwave power (IEC60705) 2,450 MHz 2M282 0 ~ 60 min. 21

/4” (W) x 141/4” (H) x 177/8” (D)

/4” (W) x 87/8” (H) x 163/8” (D)

51 kg 58 kg Touch Control System Clock : 00 ~ 60 Microwave Power for Variable Cooking Power level HIGH-------------------------------------------Full power throughout the cooking time 70% (Med.-High)

--------------------

approx. 70% of Full power 50% (Med.-Low)----------------------------approx. 50% of Full power 20% (Low)------------------------------------approx. 20% of Full power

Back Side

DECS11MA / DES11EA DFS11G / DFS11EA

UCS11MA / US11EA UFS11EA

240 Volts AC 50 Hz

1,700 Watts

• DO NOT operate on a 2-wire extension cord during repair and use.

• NEVER TOUCH any oven components or wiring during operation.

• BEFORE TOUCHING any parts of the oven, always remove the power plug from the outlet.

• For about 30 seconds after the oven stops, an electric charge remains in the high voltage capacitor. When replacing or checking, you must discharge the high voltage capacitor by shorting across the two terminals with an insulated screwdriver.

•

Remove your watches whenever working close to or

replacing the Magnetron.

• DO NOT touch any parts of the control panel circuit. A resulting static electric discharge may damage this P.C.B.

• NEVER operate the oven with no load.

• NEVER injure the door seal and front plate of the oven cavity.

• NEVER put iron tools on the magnetron.

• NEVER put anything into the latch hole and the interlock switches area.

• Proper operation of the microwave oven requires that the magnetron be assembled to the waveguide and cavity. Never operate the magnetron unless it is properly installed.

• Be sure that the magnetron gasket is properly installed around the dome of the tube whenever installing the magnetron.

2-1

CAUTIONS

Unlike other appliances, the microwave oven is high-voltage and high-current equipment. Though it is free from danger in ordinary use, extreme care should be taken during repair.

THE OVEN IS TO BE SERVICED ONLY BY PROPERLY QUALIFIED SERVICE PERSONNEL.

MICROWAVE RADIATION

Personnel should not be exposed to the microwave energy which may radiate from the magnetron or other microwave generating device if it is improperly used or connection. All input and output microwave connections, waveguide, flange and gasket must be secure never operate the device without a microwave energy absorbing load attached. Never look into an open waveguide or antenna while the device is energized.

Gasket

ANTENNA

COOLING FIN

MAGNETRON CHASSIS GROUND

FILAMENT TERMINALS

MAGNETRON

INSTALLATIONS

3-1

INSTALLING

1. Empty the microwave oven and clean inside it with a soft, damp cloth. Check for damage such as misaligned door, damage around the door or dents inside the cavity or on the exterior.

2. Put the oven on a counter, table, or shelf that is strong enough to hold the oven and the food and utensils you put in it. (The control panel side of the oven is the heavy side. Use care when handling.)

3. Do not block the vent and the air intake openings. Blocking vent or air intake openings can cause damage to the oven and poor cooking results. Make sure the microwave oven legs are in place to ensure proper air flow.

4. The oven should not be installed in any area where heat and steam are generated, because they may damage the electronic or mechanical parts of the unit. Do not install the oven next to a conventional surface unit or above a conventional wall oven.

5. Use microwave oven in an ambient temperature less than 104°F(40°C).

6. Place the microwave oven on a sturdy and flat surface at least 10 cm(4 inches) from the wall.

7. Place the microwave oven as far away as possible from TV, RADIO, COMPUTER, etc., to prevent interference.

8. Do not touch the front glass during or after cooking of the Grill and Combination mode. This glass is very hot during heater operating.

9. Do not operate the oven at microwave and combination mode with Grill rack placed in the cavity when the oven is empty.

EARTHING INSTRUCTIONS

This microwave oven is designed to be used in a fully earthed condition. It is imperative, therefore, to make sure it is properly earthed before servicing

WARNINGTHIS APPLIANCE MUST BE EARTHED

IMPORTANT

As the colors of the wires in the mains lead of this appliance may not correspond with the colored markings identifying the terminals in your plug, proceed as follows.

The wire which is colored green-and-yellow must be connected to the terminal in the plug which is marked with the letter E or by the earth symbol ( ) or colored green or green-and-yellow.

The wire which is colored blue must be connected to the terminal in the plug which is marked with the letter N or colored black.

The wire which is colored brown must be connected to the terminal in the plug which is marked with the letter L or colored red.

BEFORE YOU BEGIN, READ THE FOLLOWING INSTRUCTIONS COMPLETELY AND CAREFULLY.

The wires in this mains lead are colored in accordance with the following code:

Green-and-yellow: Earth Blue: Neutral Brown: Live

10cm

Display

Pads

Some items in display can be seen but will not glow.

FEATURES

CONTROL PANEL

4-1

OPERATING INSTRUCTIONS



Window Door Screen

Electronic Control

Safety Door Lock System

TIME ENTRY Use to enter heating time without changing

preprogrammed number pads.

Pads 1-0 Use to begin heating with preprogrammed

times and power levels or to enter times for “Manual Time Entry” cooking.

HOLD 0%, Use to select power level. Oven can heat at

full or reduced power. If oven power level is set to 0% oven does not heat for programmed time. If no power level is selected, oven operates at 100% power.

STOP/RESET Use to exit programming mode and stop

cooking during cooking cycle.

START Use to start “Manual Time Entry” program

or restart interrupted cooking cycle. Use to advance to next user option. Use to save times and power levels when programming pads.

DEFROST 20%, MEDIUM 50%, MED-HI 70%

DES11EA / US11EA

4-2

FEATURES

CONTROL PANEL

OPERATING INSTRUCTIONS



Window Door Screen

Electronic Control

Safety Door Lock System

DFS11EA / UFS11EA

Display

Some items in display can be seen but will not glow.

Pads

Use to enter heating time without changing preprogrammed number pads.

Use to begin heating with preprogrammed times and power levels or to enter times for “Manual Time Entry” cooking.

Use to select power level. Oven can heat at full or reduced power. If oven power level is set to 0% oven does not heat for programmed time. If no power level is selected, oven operates at 100% power.

Use to exit programming mode and stop cooking during cooking cycle.

Use to start “Manual Time Entry” program

Use to automatically increase the  programmed time for double quantities.

or restart interrupted cooking cycle. Use to advance to next user option. Use to save times and power levels when programming pads.

TIME ENTRY

Pads 1-0

POWER LEVEL

STOP/RESET

START

QTY2x

4-3

FEATURES

CONTROL PANEL

OPERATING INSTRUCTIONS



Window Door Screen

Electronic Control

Safety Door Lock System

DECS11MA / UCS11MA

Display

Some items in display can be seen but will not glow.

Pads

Use to enter cooking time.

Use to begin heating with preprogrammed times and power levels.

Use to select power level. Oven can heat at full or reduced power.

Use to start “Manual Time Entry” program or restart interrupted cooking cycle. Use to advance to next user option. Use to save times and power levels when programming pads.

DIAL

QUICK SET

START

70%,

50%,

DEFROST



4-4

FEATURES

CONTROL PANEL

OPERATING INSTRUCTIONS



Window Door Screen

Electronic Control

Safety Door Lock System

DFS11G

Display

Some items in display can be seen but will not glow.

Pads

Use to enter heating time without changing preprogrammed number pads.

Use to begin heating with preprogrammed

Use to enter times for “Manual Time Entry”

times and power levels or to enter times for “Manual Time Entry” cooking.

cooking. Use to select power level. Oven can heat at

full or reduced power. If oven power level is set to 0% oven does not heat for programmed time. If no power level is selected, oven operates at 100% power.

Use to exit programming mode and stop cooking during cooking cycle.

Use to start “Manual Time Entry” program

Use to automatically increase the  programmed time for double quantities.

or restart interrupted cooking cycle. Use to advance to next user option. Use to save times and power levels when programming pads.

TIME ENTRY

DIAL

Pads 1-0

POWER LEVEL

STOP/RESET

START

QTY2x

4-5

Cooking Displays

Shows when power is connected to oven. Open and close door to clear.

READY shows when oven control will accept entries. Appears after oven door is opened and closed.

33:33 shows heating time. When more than 1 heating stage is programmed, total time for all stages displays.

COOK shows when oven is operating. 20 indicates the microwave power level used. If power level

does not show, oven is heating at 100% power.

Cooking DisplaysCooking DisplaysCooking Displays

Programming Displays

Indicates programming mode. See “Programming” section of manual for programming procedure.

Indicates programming user options mode. See “User Options” section of manual for programming procedure.

Programming DisplaysProgramming DisplaysProgramming Displays

OPERATION

4-6

To avoid fire,do not dry newspapers or clothes in microwave oven.

CAUTION

Interrupting Operation

•

Open oven door to interrupt operation. Oven fan

continues to operate.Close door and press

START

pad to resume oven operation.

• Press STOP/RESET pad to interrupt operation.

Display continues to show countdown time.Press ST AR Tpad to resume oven operation and countdown timing.

Canceling Mistakes

•

If oven is operating,press STOP/RESET pad once to stop oven,then again to clear display.

•

If oven door is open and time shows in display,close oven door and press STOP/RESET pad to clear display.

Operating Preprogrammed Pads

Oven has 10 ~ 20 preprogrammed number pads. Instructions are written for factory programmed ovens. Ovens that are reprogrammed can respond differently than described below.

1. Open oven door ,place food in oven,and close oven

door

• If pad is not pressed in 30 seconds,open and close oven door again.

2. Press desired number pad.

• Oven operates and time counts down.

3. Oven stops heating and oven signal sounds when heating timing elapses.

Operating QTY 2X Pads

1.Press Pad.

2.Press desired number pad

• Example : press + =18 sec.

QTY

1 2 3 4 5 6 7 8 9 0

10 sec. 20 sec. 30 sec. 45 sec. 1 min. 1:30 min. 2 min. 3 min. 4 min. 5 min.

01 02 03 04 05 06 07 08 09 10

Pads Pads Pads

Heating Times

Preprogrammed Times and Cook Level

All preprogrammed pads arrive set at full power.

Option: Single Digit

11 12 13 14 15 16 17 18 19 20

10 sec. 20 sec. 30 sec. 45 sec. 1 min. 1:30 min. 2 min. 3 min. 4 min. 5 min.

20 sec. 40 sec. 1 min. 1:30 min. 2 min. 3 min. 4 min. 6 min. 8 min. 10 min.

Option: Double Digit

Manual Time Entry

Manual Time Entry feature allows the operator to enter time and power levels, and heat without changing the preprogrammed pads.

1. Open oven door, place food in oven, and close door.

• Display shows "READY".

• If pad is not pressed in 30 seconds, open and close oven door again.

2. Press TIME ENTRY pad.

• Display shows "00:00".

3. Press number pads to enter desired cooking time.

• For example, to heat for 2 minutes 30 seconds, press 2, 3, and 0 pads.

4. Press desired power level pad to change power level.

• If a power level pad is not pressed, oven defaults to 100% power.

• For example, pressing MEDIUM 50% pad sets oven to 50% power.

• Display shows current power level if other than 100 percent power.

5. Press START pad.

• Oven operates and time counts down.

6. Oven stops heating and oven signal sounds when heating timing elapses.

4-7

PROGRAMMING

Preprogrammed Number Pads

Oven has 10~20 preprogrammed number pads. Follow instructions below to program heating times and power levels for customized cooking.

1. Open oven door.

• If door is closed or RESET pad is pressed before finishing programming sequence, oven exits programming mode.

2. Press and hold pad 1 for approximately 5 seconds.

• After 5 seconds, signal sounds. Display shows

“PROGRAM” indicating program mode.

3. Press desired number pad.

• Display shows heating time, “COOK LEVEL” and

power level if other than 100 percent power.

4. Press number pads to enter desired cooking time.

• For example, to heat for 2 minutes 30 seconds, press

2, 3, and 0 pads.

5. Press desired power level pad to change power level.

• If a power level pad is not pressed, oven defaults to

100% power.

• For example, pressing MEDIUM 50% pad sets oven to

50% power.

• Display shows current power level if other than 100%

power.

6. Press START pad to save new heating time and power level in oven memory.

• Repeat step 3-6 to program additional pads.

7. Press RESET pad or close oven door to exit programming mode.

Multiple Heating Stages

Follow instructions below to program oven to perform 3 consecutive heating cycles without interruption.

1. Open oven door.

• If door is closed or RESET pad is pressed before finishing programming sequence, oven exits programming mode.

2. Press pad 1 for approximately 5 seconds.

• After 5 seconds, signal sounds.

3. Press desired number pad.

• Display shows heating time and preprogrammed number.

4. Press number pads to enter desired cooking time.

• For example, to heat for 2 minutes 30 seconds,

5. Press desired power level pad to change power level.

• If a power level pad is not pressed, oven defaults to

100% power.

• For example, pressing MEDIUM 50% pad sets

oven to 50% power.

• Display shows current power level if other than 100

percent power.

6. Press TIME ENTRY pad.

• Display briefly shows "STAGE 2" . Then cook time

and power level for stage show in display.

• Repeat steps 5-6 to create additional stages.

7. Press START pad to save new heating time and power level in oven memory.

8. Press RESET pad or close oven door to exit programming mode.

4-8

User Options

Follow the instructions below to customized the microwave oven’s operation. End-of-cycle signal, maximum heating time and other options can be changed to meeting your cooking needs.

1. Open oven door.

• If door is closed or RESET pad is pressed before finishing programming sequence, oven exits programming mode.

2. Press and hold pad 2 for approximately 5 seconds.

• After 5 seconds, signal sounds. Display shows “OPTION”.

3. Press number pad that matches desired option.

• “OP” represents optional program mode, first number represents option number and second number represents functions currently selected for option.

4. Press START pad to advance to next option. See table for options.

5. Press number pad (0,1-3) to change option.

6. Press START pad to save changes.

• Repeat steps 4-6 to change additional options.

7. Press STOP/RESET pad or close oven door to exit programming mode.

Optional Program Indicator

Pad Number

Option Selected

Numbered Pads Display Options (Factory Settings in Bold)

End of Cycle Beep

OP:10

OP:11 OP:12

3 second beep.

Continuous beep until door is opened. 5 beep bursts until door is opened.

Speaker Volume

OP:20 OP:21 OP:22

OP:23

Eliminates beep. Sets volume to low. Sets volume to mediu m.

Sets vo lume to hi g h.

Key Beep

OP:30

OP:31

Prevents beep when pad is pressed.

Allows beep when pad is pressed.

Keyboard Enable

Window

OP:40 OP:41

OP:42

OP:43

15 seconds after oven door is opened, k eyboard disabled. 30 seconds after oven door is opened, k eyboard disabled.

1 minute after oven door is opened, keyboard disabled.

2 minutes after oven door is opened, keyboard disabled.

Add Time During

Heating

OP:50

OP:51

Prevents adding heating time while oven i s heating.

Allows heating time to be changed while oven is heating when a memory pad is pressed.

Reset Door Open

OP:60

OP:61

Allows oven to resume heating time countdown after door is opened during cycle.

Cancels heating time count down after door is opened during cycle.

(some models)

Maximum Heating Time

OP:70

OP:71

Allows 60 minutes of heating time (some models). Allows 10 minutes of heating time.

Manual Operation

OP:80

OP:81

Allows use of preprogrammed pads only.

Allows use of manual tim e entry and preprogrammed pads.

(some models)

Double Digit Operation

OP:90

OP:91

Allows 10 (0-9) preprogrammed pads .

Allows 100 (00-99) preprogrammed pads.

Clean Filter Message

OP:00 OP:01 OP:02 OP:03

Do not display message. Display message for 24 hours every 7 days. Display message for 24 ho urs every 30 days. Display message for 24 ho urs every 90 days.

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