Samsung M735 User manual

MICROWAVE OVEN
M735
SERVICE
Manual
MICROWAVE OVEN CONTENTS
400
560
120
M735
800W
12
3
4
5
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50
250
1. Precaution
2. Specifications
3. Operating Instructions
4. Disassembly and Reassembly
5. Alignment and Adjustments
6. Troubleshooting
7. Exploded Views and Parts List
8. Wiring Diagram
NSI

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/cm2
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
about 30 seconds after disconnection. Short
the negative terminal of the high-voltage
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
Samsung Electronics 2-1
M735
POWER SOURCE 230V 50Hz, SINGLE PHASE
POWER CONSUMPTION 1300W
OUTPUT POWER 120W/800W
OPERATING FREQUENCY 2450MHz
TIMER 60 MINUTES
COOLING METHOD AIR COOLING
MAGNETRON OM75SH(31)ESST
OUTSIDE DIMENSIONS 489(W) x 356(D) x 275(H)mm
OVEN CAVITY DIMENSIONS 306(W) x 322(D) x201(H)mm
SHIPPING WEIGHT APPROX. 14.5 Kg

3. Operating Instructions
3-1 Control Panel
Samsung Electronics 3-1
400
560
120
M735
800W
12
3
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7
8
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20
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489mm
357mm
275mm
200mm
356mm
400
560
120
M735
800W
12
3
4
5
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3-2 Samsung Electronics
NOTE: The oven must be plugged into an
appropriate wall socket.
The glass plate must be in position in the
ovn.
1. Open the oven door by pushing the OPEN DOOR
button. Place a glass of water on the glass plate.
Close the door.
2. Set the power level to 100%(maximum) by
turning COOKING POWER CONTROL knob.
3. Set the time to 4 to 5 minutes by turing TIMER
knob.
Important: If any problem is experienced in the
operation of the oven, please refer to
the section on page 4 "what to do if
you are in doubt or have a problem."
Operating Instruction
3-3 Checking That Your Oven is Operating Correctly
3-2 Features & External Views
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Door Ventilation Slot Light Safety Interlock Holes
Control Panel
Open Door Push Button
Guide Roller
Glass Tray
Door Latches
400
560
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M735
800W
12
3
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5
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

3-4 Variable Power Cooking Chart
Samsung Electronics 3-3
1. Place the frozen food in the oven and close the
door.
2. Turn the COOKING POWER CONTROL knob
to Defrost symbol.
3. Turn the TIMER knob to select appropriate
time.
Result: Defrosting begins.
When Defrosting has finished, the oven
beeps.
Operation:
Set the COOKING POWER CONTROL
knob to the appropriate power level by
turning it.
Operating Instruction
% OUTPUT
M735
HIGH 100% 800W
MEDIUM HIGH 70% 560W
MEDIUM 50% 400W
LOW 30% 240W
DEFROST 20% 160W
WARM 15% 120W
3-5 Adjusting the Cooking Time During Cooking
Stopping the Cooking Adding Extra Time
To stop the cooking.... Press....
Temporarily Open Door.
To resume cooking, close the door.
Completely Turn the TIMER knob to 'O'
Simply move the timer knob to any increased setting that
you require.
3-6 Manual Defrosting Food
400
560
120 800W
240
3-7 Instant Cook Guide
1. Place the food in the oven and close the door.
2. Turn the COOKING POWER CONTROL knob
to Max Power.
3. Turn the TIMER knob to select instant cook,
drinks, soup/sauce and fresh vegetables.
Symbol Recipes Serving Size Power level Standing Time
Soup/
Sauce
Fresh
Vegetables
200~300
g100% 2~3mins
Drink
200~300
ml
150 mL
100%
100%
2~3mins.
2~3mins.
POWER LEVEL

4-1 Samsung Electronics
Remove the magnetron including the shield case,
permanent magnet, choke coils and capacitors (all
of which are contained in one assembly).
1. Disconnect all lead wires from the magnetron
and lamp.
2. Remove a screw securing the magnetron
supporter.
3. Remove the magnetron supporter.
4. Remove the air cover.
5. Remove screws securing the magnetron to the
wave guide.
6. Take out the magnetron very carefully.
7. Remove screws from the back panel.
8. Take out the fan motor.
9. Remove the oven lamp by rotating to pull out
from hole of air cover.
NOTE1: When removing the magnetron, make
sure that its antenna does not hit any
adjacent parts, or it may be damaged.
NOTE2: When replacing the magnetron, be
sure to remount the magnetron gasket
in the correct position and make sure
the gasket is in good condition.
1. Discharge the high voltage capacitor.
2. Disconnect all the leads.
3. Remove the mounting bolts.
4. Reconnect the leads correctly and firmly.
Lamp
Magnetron
H. V. Trans
H. V. Capacitor
Nuts or Screw
Thermo S/W
Fan Motor
H. V. Trans
Screws
4. Disassembly & Reassembly
4-1 Replacement of Magnetron, Motor Assembly and Lamp
4-2 Replacement of High Voltage Transformer

Samsung Electronics 4-2
Disassembly & Reassembly
Upper Hinge
Lower Hinge
Screws
Door "E" Key Door Spring
Screw
4-3 Replacement of Door Assembly
4-3-1 Removal of Door Assembly
Remove hex bolts securing the upper hinge and
lower hinge. Then remove the door assembly.
Insert flat screwdriver into the gap between Door
"E" and Door "C" to remove Door "C". Be careful
when handling Door "C" because it is fragile.
Following the procedure as shown in the figure,
insert and bend a thin metal plate between Door
"E" and Door "A" until you hear the 'tick' sound.
1. Insertion depth of the thin metal plate should be
0.5mm or less.
4-3-4 Removal of Key Door & Spring
Remove pin hinge from Door "E"
Detach spring from Door "E" and key door.
4-3-2 Removal of Door "C"
4-3-3 Removal of Door "E"

4-3 Samsung Electronics
1. Disconnect the oven from the power source.
2. Remove the 10A fuse in the fuse holder.
3. When replacing the 10A fuse, be sure to use an exact replacement part. If new 10A fuse blows out again
after replacement, check the primary interlock switch, door sensing switch and interlock monitor switch.
4. When the above three switches operate properly, check if any other part such as the control circuit board,
blower motor or high voltage transformer is defective.
1. Take out the glass tray, guide roller and coupler
from cavity.
2.
Turn the oven upside down to replace the drive motor.
3. Remove a screw securing the drive motor cover.
4. Disconnect all the lead wires from the drive motor.
5. Remove screws securing the drive motor to the
cavity.
6. Remove the drive motor.
7. When replacing the drive motor, be sure to
remount it in the correct position.
8. Connect all the leads to the drive motor.
9. Screw the deive motor cover to the base plate
with a screw driver.
10. Remount the coupler in the correct position.
Disassembly &ReaAssembly
Screw
Drive Motor Cover
Base Plate
Drive Motor
4-3-5 Reassembly Test
After replacement of the defective component parts of the door, reassemble it and follow the instructions below for proper
installation and adjustment so as to prevent an excessive microwave leakage.
1. When mounting the door to the oven, be sure to adjust the door parallel to the bottom line of the oven
face plate by moving the upper hinge and lower hinge in the direction necessary for proper alignment.
2. Adjust so that the door has no play between the inner door surface and oven front surface. If the door
assembly is not mounted properly, microwave energy may leak from the space between the door and
oven.
3. Do the microwave leakage test.
4-4 Replacement of Fuse
4-5 Replacement of Drive Motor

Samsung Electronics 5-1
1. Remove connectors from the transformer
terminals and check continuity.
2. Normal resistance readings should be as
follows:
Secondary ..........................Approx. 123W
Filament .............................Approx. 0W
Primary...............................Approx. 2.30W
(Room temperature = 20˚C)
1. Continuity checks can only indicate an open
filament or a shorted magnetron. To
diagnose an open filament or shorted
magnetron.
2. Isolate the magnetron from the circuit by
disconnecting its leads.
3. A continuity check across the magnetron
filament terminals should indicate one ohm
or less.
4. A continuity check between each filament
terminal and the magnetron case should read
"open".
Magnetron Antenna
Cooling Fins
Gasket Plate
5. Alignment and Adjustments
5-1 High Voltage Transformer
5-2 Magnetron
PRECAUTION
1. High voltage is present at the high voltage terminal of the high voltage transformer during any cook cycle.
2. It is neither necessary nor advisable to attempt measurement of the high voltage.
3. Before touching any oven components, or wiring, always unplug the oven from its power source and discharge the high voltage
capacitor.
Filament Terminals Secondary Terminal
Primary
Terminals

5-2 Samsung Electronics
5-5 Adjustment of Primary Switch, Secondary Switch and Monitor Switch
1. When mounting Primary switch and
Interlock Monitor switch to Latch Body,
consult the figure below.
2. NOTE: No specific adjustment during
installation of Primary switch and Monitor
switch to the latch body is necessary.
3. When mounting the Latch Body to the oven
assembly, adjust to the Latch Body by
moving it so that the oven door will not have
any play. Check for play in the door by
pulling the door assembly. Make sure that
the latch keys move smoothly after
adjustment is completed. Completely tighten
the screws holding the Latch Body to the
oven assembly.
4. Reconnect to Monitor switch and check the
continuity of the monitor circuit and all latch
switches again by following the components
test procedures.
5. Confirm that the gap between the switch
housing and the switch actuator is no more
than 0.5mm when door is closed.
Precaution
For continued protection against radiation hazard, replace parts in accordance with the wiring diagram and be sure to use the
correct part number for the following switches.: Primary and secondary interlock switches and the interlock monitor switch all
together. Then follow the adjustment procedures below. After repair and adjustment, be sure to check the continuity of all
interlock switches and the interlock monitor switch.
Door Open Door Closed
Primary switch ¥0
Monitor switch (COM-NC) 0 ¥
Monitor switch (COM-NO) ¥0
Secondary switch ¥ 0
Alignment and Adjustments
5-3 High Voltage Capacitor
1. Isolate the diode from the circuit by disconnecting its leads.
2. With the ohm-meter set at the highest resistance scale, measure the resistance across the diode
terminals. Reverse the meter leads and read the resistance. A meter with 6V, 9V or higher voltage
batteries should be used to check the front-to back resistance of the diode, otherwise an infinite
resistance may be read in both directions. The resistance of a normal diode will be infinite in one
direction and several hundred KWin the other direction.
5-4 High Voltage Diode
1. Check continuity of the capacitor with meter set at the highest ohm scale.
2. Once the capacitor is charged, a normal capacitor shows continuity for a short time, and then
indicates 10MW.
3. A shorted capacitor will show continuous continuity.
4. An open capacitor will show constant 10MW.
5. Resistance between each terminal and chassis should read infinite.
Primary Interlock Switch
Lever Door
Body Latch
SECONDARY
Switch
Interlock
Monitor
Switch

5-7 Microwave Heat Distribution - Heat Evenness
Samsung Electronics 5-3
5-6 Output Power of Magnetron
The microwave heat distribution can be checked indirectly by measuring the water temperature risen at
certain positions in the oven :
1. Prepare five beakers made of 'Pyrex', having 100 milliliters capacity each.
2. Measure exactly 100milliliters off water load with a measuring cylinder and pour it into each beaker.
3. Measure the temperature of each water load.
(Readings shall be taken to the first place of decimals.)
4. Put each beaker in place on the cooking tray as illustrated in figure
below and start heating.
5. After heating for 2 minutes, measure the temperatures of water in
each beaker.
6. Microwave heat distribution rate can be caicviated as follows :
Minimum
Temperature Rise
Heat Distribution = X 100(%)
Maximum
Temperature Rise
The result should exceed 65%.
The output power of the magnetron can be measured by performing a water temperature rise test.
Equipment needed
* Two 1-liter cylindrical borosilicate glass vessel (Outside diameter of 190mm)
* One glass thermometer with mercury column
NOTE: Check line voltage under load. Low voltage will lower the magnetron output. Make all
temperature and time tests with accurate equipment.
1. Fill the one liter glass vessel with one liter of water.
2. Stir water in glass vessel with thermometer and record glass vessel's temperature as T1. (10±1ûC)
3. After moving the water into another glass vessel, place it on the center of the cooking tray. Set the oven
to high power and operate for 52.3 seconds exactly. (2 seconds included as a holding time of magnetron
oscillation)
4. When heating is finished, stir the water again with the thermometer and measure the temperature rise
as T2.
5. Subtract R1 from T2. This will give you the water temperature rise. (DT)
6. The output power is obtained by the following formula;
4.187 x 1000 x DT 52.3 : Heating Time (sec)
Output Power = 4.187 : Coefficient for Water
52.3 1000 : Water (cc)
DT : Temperature Rise (T2-T1)
* Output (W) = 100 x D
7. Normal temperature rise for this model is 9ûC to 11ûC at 'HIGH'.
NOTE 1: Variations or errors in the test procedure will cause a variance in the temperature rise.
Additional power test should be made if temperature rise is marginal.
NOTE 2: Output power in watts is computed by multiplying the temperature rise (step E) by a power
factor of 91 in case of centigrade temperature.
Alignment and Adjustments
CAUTION
MICROWAVE RADIATION
PERSONNEL SHOULD NOT ALLOW EXPOSWRE TO MICROWAVE RADIATION FROM MICROWAVE GENERATOR OR
OTHER PARTS CONDUCTING MICROWAVE ENERGY.
D
D
D/4
D/4
D/4
D/4
Cooking Tray
Beaker

5-4 Samsung Electronics
1) Pour 275±15cc of 20±5ûC(68±9ûF) water in a
beaker which is graduated to 600cc, and place
the beaker in the center of the oven.
2) Start to operate the oven and measure the
leakage by using a microwave energy survey
meter.
3) Set survey meter with dual ranges to 2,450MHz.
4) When measuring the leakage, always use the 2
inch spacer cone with the probe. Hold the probe
perpendicular to the cabinet door. Place the
spacer cone of the probe on the door and/or
cabinet door seam and move along the seam,
the door viewing window and the exhaust
openings moving the probe in a clockwise direction at a rate of 1 inch/sec. If the leakage testing of the
cabinet door seam is taken near a corner of the door, keep the probe perpendicular to the areas making
sure that the probe end at the base of the cone does not get closer than 2 inches to any metal. If it gets
closer than 2 inches, erroneous readings may result.
5) Measured leakage must be less than 4mW/cm2, after repair or adjustment.
Alignment and Adjustments
5-13 Leakage Measuring Procedure
5-10 Procedure for Measurement of Microwave Energy Leakage
5-12 Note on Measurement
5-11 Check for Microwave Leakage
5-13-1 Record keeping and notification after measurement
1) After adjustment and repair of a radiarion preventing device, make a repair record for the measured
values, and keep the data.
2) If the radiation leakage is more than 4 mW/cm2after determining that all parts are in good condition,
functioning properly and the identical parts are replaced as listed in this manual notift that fact to ;
CENTRAL SERVICE CENTER
5-13-2 At least once a year have the microwave energy survey meter checked for accuracy by its
manufacturer.
1. Remove the outer panel.
2. Pour 275±15cc of 20±5ûC(68±9ûF) water in a
beaker which is graduated to 600cc, and
place the beaker in the center of the oven.
3. Start the oven at the highest power level.
4. Set survey meter dual ranges to 2,450MHz.
5. Using the survey meter and spacer cone as
described above, measure arnear the
opening of magnetron, the surface of the air
guide and the surface of the wave guide as
shown in the following photo.( but avoid the
high voltage components.) The neading
should be less than 4mW/cm2.
1) Do not exceed the limited scale.
2) The test probe must be held on the grip of the handle, otherwise a false reading may result when the
operator's hand is between the handle and the probe.
3) When high leakage is suspected, do not move the probe horizontally along the oven surface; this may
cause damage to the probe.
4) Follow the recommendation of the manufacturer of the microwave energy survey meter.
Maximum allowable leakage is 5mW/cm2.
4mW/cm2is used to allow for measurement and meter accuracy
400
560
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M735
800W
12
3
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8
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Samsung Electronics 6-1
Parts Cause Diagnosis Remedy
Fuse blows Defective primary Check continuity of the primary switch terminals with Replace the primary
out when interlock switch wire removed using a multimeter. If there is continuity interlock switch
door is ary winding. between switch terminals when door is opened,
opened. the switch is defective.
Defective interlock Check continuity of the monitor switch terminals Replace the interlock
monitor switch with wire removed by using a multimeter. monitor switch
If there is continuity between switch terminals
when the door is closed, the switch is defective.
Fuse is Layer short of the The fuse will not blow right away, but if it blows in a Replace H. V. Transformer
open. secondary coil of few seconds, then there is a layer short.
H. V. Transformer If the fuse blows with H. V. Trans secondary open, the
transformer may be faulty.
1) Fuse blown out Check fuse. Replace the fuse.
2) Poor contact of Check continuity of power supply cord. Also check Adjust or replace the
power cord whether the power cord is securely wired. power supply cord.
3) Defective lamp The fan motor rotates, but lamp does not light. Replace the lamp.
Oven lamp 4) Defective timer Check the terminals of timer for continuity, Replace the timer.
does not contacts turning the timer knob ON and OFF repeatedly.
light.
5) Thermal cutout In this case the oven lamp and fan do not Replace the
S/W open turn on thermal cutout S/W
1) Defective If 220~230V is found at motor terminals, the motor Replace the motor.
Fan does fan motor. should be replaced.
not operate.
2) Defective con- The oven lamp does not light and fan motor Replace the timer.
tacts of timer does not operate.
NOTE: Interlock monitor switch must be replaced when the fuse is blown out.
WARNING FOR HIGH VOLTAGE
4000 VOLTS EXIST AT THE HIGH VOLTAGE AREA. DO NOT OPERATE THE OVEN WITH CABINET PARTS REMOVED. DO NOT
REMOVE THE CABINET PARTS IF THE POWER SUPPLY CORD IS PLUGGED IN THE WALL OUTLET. UNPLUG THE POWER CORD
BEFORE SERVICING.
6-1 Electrical Malfunction
6. Troubleshooting

6-2 Samsung Electronics
Parts Cause Diagnosis Remedy
1) Too small If a small amount of food is heated for a long time, To increase the oven
a load period of microwave may turn off during operation. load, add a glass of
Microwave water into the oven.
turns off
during cook- 2) Defective Check to see if the magnetron thermal cutout switch is Replace thermal cutout
ing cycle. magnetron activated at a temperature higher than 150˚C. switch.
thermal
cutout S/W
Electric Incomplete Make sure that qrounding of the power supply cord has Rewire.
shock is qrounding been done properly.
felt.
Door does 1) Broken door Remove the cabinet for inspection. Replace door hinges.
not operate hinges Check the door hinge.
properly
2) Missing or Check if the screws are secured well to the door hinge. Fasten or tighten.
loose screw
1) Defective If the timer does not operate with 220~230V applied to the Replace timer.
Timer does timer motor terminals, the timer motor amy be faulty.
not operate.
2) Defective The lamp does not light. Replace timer
contacts
of timer S/W
Cooking tray 1) Defective Check to see if 21V exists at the motor terminals. Replace drive motor.
does not drive motor If so, motor will be defective.
rotate.
1) Blocking of Check if the air inlet or outlet ventilation is blocked Keep a distance of
the ventilatior by the wall or other objects. 100mm from the
wall or the objects.
Magnetron 2) Defective If the fan motor does not operate with 220~230V applied Replace fan motor.
thermal fan motor to the terminal, the motor may be faulty.
cutout
switch 3) Too small a If a small amount of food is heated repeatedly over To increase the oven
OFF load or no a long period of time, microwave turns off during load, place a glass of
load operation. water into the oven.
6-1 Electrical Malfunction (Continved)
Troubleshooting

Samsung Electronics 6-3
Parts Cause Diagnosis Remedy
1) Open cathode Check the terminals with a multimeter to see Replace magnetron.
of magnetron if the heater circuit is open.
2) Defective Check the H. V. Diode for continuity in the reverse and Replace H. V. Diode.
- H. V. Diode normal directions using megger. If there is continuity
in the reverse direction, the H. V. Diode may be faulty.
(In this event H. V. Capacitor will be hot)
3) Shorted Connect megger leads to quick-connect terminal & Replace magnetron.
magnetron body of the magnetron if there is continuity, the
magnetron may be faulty. (In this case the main
fuse will be blown)
Food is 4) Defective If there is a crack in the magnetron antenna (dome), Replace magnetron.
not heated. magnetron the magnetron is defective.
5) Poor contact Check if the screws are secured well to the door hinge. Replace or adjust.
of primay and pressing it ON and OFF repeatedly.
interlock switch
6) Open coil of Check the continuity of primary coil and secondary Replace the
H. V. Trans- coil. If there is no continuity, H. V. Transformer is H. V. Transformer.
former defective.
7) Shorted H. V. Check the continuity of capacitor. Replace the
capacitor If the capacitor shorts, the fuse blows H. V. Capacitor.
8) Monitor fuse Check the monitor fuse Replace the
blown out (on the noise filter) Monitor fuse
6-2 Unsatisfactory Cooking
Symptom Related Parts Check Points Remedy
Microwave H.V.Transformer 1) Check if the primary and secondary coil is open or shorted. Replace.
cooking does * Resistance of primary coil: Approx. 2.30 W
not work. Resistance of secondary coil: Approx. 123W
2) Check if the MGT Heater Voltage is approx. 3.3V AC.
Caution : High voltage !
H.V.Capacitor Check continuity of capacitor between two Replace.
terminals with H.V.wire lead removed.
The resistance should be approx. 10MW, it's failure.
H.V.Diode 1) If there is no continuity in forward, direction the H.V.Diode is open. Replace.
2) If there is continuity in reverse direction, it's shorted.
Fan motor Fan motor Check if the motor coil is open. Replace.
does not rotate.
6-3 Part Check List
Troubleshooting

7-1 Samsung Electronics
7. Exploded Views and Parts List
7-1 Main Exploded View
M1
M2
M3
M4
M5
M6
M7
M8
M13
M12
M9
B2
B3
B4
B1
M10
M21
M23
M24
M25
M26
M27
M28
M29
M30
M31
M15
M17 M16
M19
M18
M14
M22
M20
D3
D2
D1
D7 D8
D4
D5
D9
D10
D6
C6
C5
C4
C7
C2
C3
C1
M32

Samsung Electronics 7-2
7-2 Main Parts List
Ref. No. Parts No. Description/Specification Q'ty Remarks
M 1 DE70-30116B PANEL-OUTER;SECC,T0.6,W351.7,L1014.7,WHT-C 1 -
M 2 DE63-90035G CUSHION-RUBBER;DFA20,T2,W190,L100,BLK,-,-,- 1 PN/OUT
M 3 DE39-20054D ASSY POWER CORD;KKP-4819D/B206,250V6A,L1500 1 -
M 4 DE39-40539A WIRE HARNESS-A;230V50HZ,M935,-,-,-,- 1 -
M 5 DE91-40095A ASSY NOISE FILTER;SN-E10D(N),250V,10A,2ND-WD-TYP 1 -
M 6 DE31-30031A FAN-MOTOR;SMF745EA,230V/50HZ,ASSY-FAN-MO 1 -
M 7 DE47-20009A THERMOSTAT;PW2N-520PB,160/60,250V/7.5A,H, 1 MG-TCO
M 8 DE03-30029A MAGNETRON;OM75SH(31)ESS,-,-,-,-,- 1 -
M 9 DE93-20001A ASSY BODY LATCH;2ND-W1,M97G45/M9745,-,-,- 1 -
M10 4713-001004 LAMP-INCANDESCENT;230V,-,40W,ORG,-,-,25x71mm 1 CV/AIR
M12 DE71-60010A COVER-AIR;PP(TB53),T1.7,WHT,64G,M745,-,- 1 -
M13 DE65-20017A BUSHING CORD;IC-005,-,-,-,-,-,-,- 1 -
M14 DE66-90013A LEVER-DOOR;POM(F20-01),NTR,MW5630T,-,-,-, 1 -
M15 DE26-10121B TRANS-H.V;SHV-745EC1,230V,50HZ,KEC,2230V 1 -
M16 DE61-50106A BRACKET-HVC;SECC,T0.8,W31,L125.8,-,-,- 1 -
M17 2501-001016 C-OIL;950nF,2.1KV,BK,35x54x80,20mm 1 -
M18 DE91-70063A ASSY-HVD;V2M6,PI9.0,0.05MT,-,- 1 -
M19 DE91-70061B ASSY-H.V.FUSE;THV060T-0750-H,5KV0.75A,RED,-, 1 -
M20 DE61-40017A FOOT;PP(A353),BLK,MW5630T,-,-,- 2 -
M21 DE31-10154A MOTOR-DRIVE;M2HJ49ZR02,ST-16,21V,05ø˘ 06¿œ 1 -
M22 DE80-10003A BASE-PLATE;SGCC1-Z,T0.8,W340,L550,M745,-, 1 -
M23 DE47-20033A THERMOSTAT;PW-2N,80/70,125V15A/250V7.5A,1 1 CV-TCO
M24 DE71-60011A COVER-MGT;PP,T2.0,WHT,M745,-,-,-,-,- 1 -
M25 3601-000448 FUSE-FERRULE;250V,10A,SLOW-BLOW,CERAMIC,6.3 1 -
M26 3601-001126 FUSE-FERRULE;250V,1.6A,QUICK-ACTING,CERAMIC 1 -
M27 DE92-40165B ASSY DOOR;PUSH,WHT,M735/M745(SAW),WHT/BA 1 -
M28 DE93-30360A ASSY CONTROL-BOX;M735(SAW),-,-,-,-,-,- 1 -
M29 DE74-20102B TRAY-COOKING;GLASS,T5.0,PI288,780G,M745,-,- 1 -
M30 DE92-90436A ASSY-GUIDE ROLLER;D16.5,MW4370W,-,-,-,- 1 -
M31 DE67-60002A COUPLER;PPS,5GR,BRN,M97G45,-,-,-,- 1 -
M32 DE27-10020A COIL-MC CHOKE;TC,101 1 -
: Option Parts
: Warning : Electrostatically Sensitive Devices
Exploded Views and Parts List

7-3 Samsung Electronics
Ref. No Parts No. Description / Specification Q'ty Remarks
D 1 DE67-20004A SCREEN-DOOR;ACRYL T1.5 W173.6 L373.5 WHT MW 1
D 2 DE02-00125A TAPE-DOUBLE FACE;ACRYL T0.45 W9 WHT WF103 1
D 3 DE64-40007A DOOR-A;ABS (HR-0370D) T3.0 WHT M745 1
D 4 DE92-50126D ASSY DOOR-E;M745,-,BLK,ASSY PURCHASING 1
D 5 DE64-40008B DOOR-C;PP T1.5 W L G BLK CE745G 1
D 6 DE01-00003A FILM-DOOR;PE-FILM T0.15 W143 L265 M745 1
D 7 DE64-40006A DOOR-KEY;POM(TC3005) T2.0 12GR BLK CE945G 1
D 8 DE61-70033A SPRING-KEY;ES HSWR10 PI0.6 D6.0 L22.3 BLUIN 1
D 9 DE61-80004A HING-LOWER;SCP1,T2.3,ZN-COATING,M745 1
D10 DE61-80005A HING-UPPER;SCP1,T2.3,ZN-COATIN,M745 1
7-3 Assembly Door Parts List
Exploded Views and Parts List
Ref. No Parts No. Description / Specification Q'ty Remarks
C 1 DE66-20006A BUTTON-PUSH;RESIN-ABS(HR-0370U) P/WHT M945 1
C 2 DE61-70076A SPRING-BUTTON;HSWR PI0.6 1
C 3 DE64-10123A KNOB;PURE-WHT M97G35 2
C 4 DE72-70006A CONTROL-PANEL;ABS WHT M735(SAW) 1
C 5 DE45-10074A TIMER-ASSY;TMFK60MTAL 220/240V-50HZ CMO-TYP 1
C 6 3501-000309 RELAY-POWER;CHP11-A240S-250V15A 240V,3750VA 1
C 7 DE93-30532D ASSY CONTROL-PANEL;M735(SDW,SSW) 1
7-4 Assembly Control Box Parts List
Ref. No Parts No. Description / Specification Q'ty Remarks
B 1 DE66-40001A LATCH-BODY;POM(F20-02) 40GR NTR 1
B 2 3405-000178 SWITCH-MICRO;250V,15A,200gf,SPST-NO 2
B 3 3405-000175 SWITCH-MICRO;250V,15A,200gf,SPST-NO 1
B 4 DE66-90001A LEVER-SWITCH;P.O.M(F20-02) 2 6 NTR 2ND-W 1
7-5 Assembly Body Latch Parts List