SAMSUNG CE979GSETAW Service Manual

MICROWAVE OVEN

CE979GSE

SERVICE

Manual

MICROWAVE OVEN

CONTENTS

1. Precautions

2. Specifications

3. Operating Instructions

4. Disassembly and Reassembly

5. Alignment and Adjustments

6. Circuit Description

7. Troubleshooting

8. Exploded Views and Parts List

9. PCB Diagrams

10. Schematic Diagrams

TAWIL

Samsung Electronics

(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.

PRECAUTIONS TO BE OBSERVED BEFORE AND DURING SERVICING TO A VOID POSSIBLE EXPOSURE TO EXCESSIVE MICROWAVE ENERGY

1. Precaution

1-1 Safety precautions ( )

Samsung Electronics 1-1

1. All repairs should be done in accordance with the procedures described in this manual. This product complies with Federal Performance Standard 21 CFR Subchapter J (DHHS).

2. Microwave emission check should be performed to prior to servicing if the oven is operative.

3. If the oven operates with the door open : Instruct the user not to operate the oven and contact the manufacturer and the center for devices and radiological health immediatly.

4. Notify the Central Service Center if the microwave leakage exceeds 5 mW/cm

2

5. Check all grounds.

6. Do not power the MWO from a "2-prong" AC cord. Be sure that all of the built-in protective devices are replaced. Restore any missing protective shields.

7. When reinstalling the chassis and its assemblies, be sure to restore all protective devices, including: nonmetallic control knobs and compartment covers.

8. Make sure that there are no cabinet openings through which people--particularly children--might insert objects and contact dangerous voltages. Examples: Lamp hole, ventilation slots.

9. Inform the manufacturer of any oven found to have emmission in excess of 5 mW/cm2, Make repairs to bring the unit into compliance at no cost to owner and try to determine cause. Instruct owner not to use oven until it has been brought into compliance.

CENTRAL SERVICE CENTER

10. Service technicians should remove their watches while repairing an MWO.

11. To avoid any possible radiation hazard, replace parts in accordance with the wiring diagram. Also, use only the exact replacements for the following parts: Primary and secondary interlock switches, interlock monitor switch.

12. If the fuse is blown by the Interlock Monitor Switch: Replace all of the following at the same time: Primary and secondary switches, as well as the Interlock Monitor Switch. The correct adjustment of these switches is described elsewhere in this manual. Make sure that the fuse has the correct rating for the particular model being repaired.

13. Design Alteration Warning: Use exact replacement parts only, i.e., only those that are specified in the drawings and parts lists of this manual. This is especially important for the Interlock switches, described above. Never alter or add to the mechanical or electrical design of the MWO. Any design changes or additions will void the manufacturer's warranty.10.Always unplug the unit's AC power cord from the AC power source before attempting to remove or reinstall any component or assembly.

14. Never defeat any of the B+ voltage interlocks. Do not apply AC power to the unit (or any of its assemblies) unless all solid-state heat sinks are correctly installed.

15. Some semiconductor ("solid state") devices are easily damaged by static electricity. Such components are called Electrostatically Sensitive Devices (ESDs). Examples include integrated circuits and field-effect transistors.

Immediately before handling any semiconductor components or assemblies, drain the electrostatic charge from your body by touching a known earth ground.

16. Always connect a test instrument's ground lead to the instrument chassis ground before connecting the positive lead; always remove the instrument's ground lead last.

Follow these special safety precautions. Although the microwave oven is completely safe during ordinary use, repair work can be extremely hazardous due to possible exposure to microwave radiation, as well as potentially lethal high voltages and currents.

17. When checking the continuity of the witches or transformer, always make sure that the power is OFF, and one of the lead wires is disconnected.

18. Components that are critical for safety are indicated in the circuit diagram by shading, or .

19. Use replacement components that have the same ratings, especially for flame resistance and dielectric strength specifications. A replacement part that does not have the same safety characteristics as the original might create shock, fire or other hazards.

1. High Voltage Warning Do not attempt to measureany of the high voltages--this includes the filament voltage of the magnetron. High voltage is present during any cook cycle.

Before touching any components or wiring, always unplug the oven and discharge the high voltage capacitor (See Figure 1-1)

2. The high-voltage capacitor remains charged for about 30 seconds after disconnection. Short the negative terminal of the highvoltage capacitor to to the oven chassis. (Use a screwdriver.)

3. High voltage is maintained within specified limits by close-tolerance, safety-related components and adjustments. If the high voltage exceeds the specified limits, check each of the special components.

1-2

Pretaution

Samsung Electronics

1-2 Special Servicing Precautions (Continued)

1-3 Special High Voltage Precautions

Fig. 1-1. Discharging the High Voltage Capacitor

2. Specifications

2-1 Table of Specifications

TIMER 99Mins POWER SOURCE 230V 50Hz, AC POWER CONSUMPTION MICROWAVE : 1,500W

MAX : 1,500W GRILL : 1,300W

OUTPUT POWER FROM 85W TO 850W (10 LEVEL POWER)

(IEC-705 TEST PROCEDURE) OPERATING FREQUENCY 2,450MHz MAGNETRON OM75PH(31)ESS COOLING METHOD COOLING FAN MOTOR OUTSIDE DIMENSIONS 517(W) x 340H) x 435(D)

2-2 Comparison Chart

MODEL

FEATURE

POWER LEVEL

ON TIME OFF TIME

% CE979GSE

10% 85W 4 sec 26 sec 20% 170W 7 sec 23 sec 30% 255W 10 sec 20 sec 40% 340W 13 sec 17 sec 50% 425W 16 sec 14 sec 60% 510W 19 sec 11 sec 70% 595W 22 sec 8 sec 80% 680W 25 sec 5 sec 90% 765W 28 sec 2 sec

100% 850W 30 sec 0 sec

CE979GSE

MORE/LESS O

AUTO COOK/DISH O AUTO DEFROST O AUTO REHEAT O TIME COOK O POWER LEVEL O GRILL O MICROWAVE/GRILL O

Samsung Electronics 2-1

3. Operating Instructions

,,,,,,,,,,,,,,,

3-1 Control Panel

Cehcop Cehcop

GRILL / COMBI

3-2 Features & External Views

DOOR LATCHES

,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,

START 1 Min

GLASS TRAY

STOP / CANCEL

deodorization

LIGHT

HEATER

,,,,,,,,,,,,,,,

DISPLAY

DOOR

VENTILATION

HOLES

GUIDE ROLLER

INHALATION

SLOT

SAFETY INTERLOCK

CONTROL PANEL

HOLES

Samsung Electronics 3-1

1. Remove five screws from the rear section.

2. Lift the outer panel by pulling it backwaeds

1. The magnetron incudes the shield case, permanent magnet, check coils and 500pF capacitors (all contained in one assembly).

2. Discharge the high voltage capacitor. (See page1-2)

3. Disconnect all lead wires from the magnetron.

4. Remove screw(1) securing the magnetron supporter.

5. Remove the magnetron supporter.

6. Remove the air cover

7. Remove screws(2) securing the thermal cutout switch.

8. Remove screws securing the magnetron to the wave guide.

9. Remove the magnetron very carefully.

10. Remove screws from the back panel to take out fan motor.

11. When removing the magnetron, make sure that its antenna does not hit any adjacent parts.

12. When replacing the magnetron, be sure to remount the magnetron gasket in the correct position, and make sure the gasket is in good condition.

4. Disassembly and Reassembly

4-1 Removal of Outer Panel

Samsung Electronics 4-1

4-2 Replacement of Magnetron and Fan Motor

Screw(1)

Screw(2)

Cover Air

Magnetron

Fan Motor

4-3 Replacement of High Voltage Transformer

4-4 Replacement of Door Assembly

4-2 Samsung Electronics

1. Discharge the high voltage capacitor. (See page 1-2)

2. Disconnect all the leads.

3. Remove four screws.

4. When replacing, connect the leads securely.

1. Remove bolts securing the upper hinge and lower hinge, then remove the door assmbly.

2. After replacing the door, check the operation of the primary interlock switch, the secondary interlock switch and the interlock monitor switch.

3. Microwave emission should not exceed 5§ /§† (All service adjustments should be made for minimum RF emission.)

Disassembly and Reassembly

H.V.TRANS

H.V.FUSE

HINGE UPPER

HINGE VOLT

H.V.CAPACITOR

4-5 Replacement of Lamp

Samsung Electronics 4-3

1. Disconnect harness-"A" assembly.

2. Remove screw securing the lamp cover

1. Remove the glass tray and assembly from cavity.

2. Turn the oven upside down.

3. Remove screws securing the elevation motor cover.

4. Disconnect all lead wires from the elevation motor.

5. Remove screws securing the elevation motor to the cavity.

6. Remove the elevation motor.

7. When replacing the elevation motor, be sure to remount it in the correct position.

8. Reconnect all the leads to the elevation motor.

9. Screw the elevation motor cover to the base plate with screw driver.

10. Remount the coupler in the correct position.

4-6 Replacement of Elevation Motor

Disassembly and Reassembly

ELEVATION MOTOR COVER

Lamp cover

Screw

ELEVATION

MOTOR

TANTABLE

MOTOR

WEIGHT SENSOR

SCREW

1. Remove the outer panel.

2. Disconnect all the connectors and terminals on

the heater and noise filter assembly.

3. Unscrew nuts securing the grill heater.

1. Disconnect all lead wires from the interlock

monitor switch and the door sensing switch.

2. Push up the mounting tabs.

3. Make necessary adjustments Do the microwave

emission check according to "ALIGNMENT AND ADJUSTMENTS" on page 5-2(whenever they any repaired or replaced).

1. Disconnect all lead wires from the primary

interlock switch.

2. Push up the mounting tabs which support the

primary interlock switch.

3. Make necessary adjustments and microwave

emision check according to "ALIGNMENT AND ADJUSTMENTS" on page 5-2(whenever they are repaired or replaced).

4-7 Replacement of Grill Heater

4-8 Replacement of Interlock Monitor Switch and Door Sensing Switch

4-9 Replacement of Primay Interlock Switch

4-4 Samsung Electronics

Disassembly and Reassembly

Interlock Switch Replacement

When replacing defective switches, be sure to check that the mointing tabs are not bent or broken.

GRILL HEATER

SCREW

PLATE SRRING

BRACKET HEATER

Primary Interlock S/W

Lever Switch

Interlock Monitor S/W

Door Sensing S/W

Body Latch

Guide S/W

1. Disconnect the oven from the power source.

2. Remove the 10A fuse from the fuse holder.

3. When replacing the 10A fuse, use an exact replacement and check the primary interlock , door sensing and interlock monitor switches.

4. When the above switches operate properly, check that the control circuit transformer is not defective.

1. Be sure to disclyarge any static electricity from your body, and avoid touching the "Touch control" clrcuitry.

2. Disconnect the connectors from the control circuit board.

3. Remove screws ¥L and ¥Msecuring the control circuit bord.

4. Lift up the control circuit board from right side and remove the hooks holding the contol circuit board to the box assembly.

1. Disconnect all lead wires from the gas sensor and the thermostat.

2. Remove screws securing the air guide.

4-10 Replacement of Fuse

Samsung Electronics 4-5

4-11 Replacement of Control Circuit Board

4-12 Replacement of Gas Sensor and ThermoSwitch

Disassembly and Reassembly

Screw¥L Screw¥M

Gas sensor

thermostat