Samsung CE1279KSE User manual

MICROWAVE OVEN
CE1279KSE
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
BWT

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.
PRECAUTIONSTOBEOBSERVEDBEFOREANDDURING
SERVICINGTOAVOIDPOSSIBLEEXPOSURETOEXCESSIVE
MICROWAVEENERGY

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.
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.

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.
17. When checking the continuity of the
switches 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 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
TIMER 99 MINUTES 00 SECONDS
POWER SOURCE 230V 50Hz, AC
POWER CONSUMPTION MICROWAVE : 1,500W
GRILL : 1,450W
CONVECTION : 1,470W
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 547(W) x 352(H) x 516(D)
POWER LEVEL
% CE1279KSE
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
ON TIME OFF TIME
2-2 Comparison Chart
MODEL
FEATURE
MORE/LESS ¡
AUTO COOK/DISH ¡
AUTO DEFROST ¡
AUTO REHEAT ¡
TIME COOK ¡
POWER LEVEL ¡
GRILL ¡
MICROWAVE+GRILL(CYCLE) ¡
MICROWAVE+CONVECTION(CYCLE) ¡
CONECTION ¡
CE1279KSE

Sensor Sensor
Auto Recipes
CLOCK
deodorization GRILL / OVEN( C)
START
1 Min
MW+GRILL MW+OVEN
STOP / CANCEL
More/Less Power Level/dish( )
3. Operating Instructions
3-1 Control Panel
Samsung Electronics 3-1
3-2 Features & External Views
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
,,,,,,,,,,,,,,,
DOOR LATCHES
DOOR
LIGHT HEATER DISPLAY
CONTROL
PANEL
INHALATION
SLOT
GUIDE
ROLLER
VENTILATION
HOLES
CERAMIC TRAY
SAFETY
INTERLOCK
HOLES

1. Remove five screws from the rear section.
2. Lift the outer panel by pulling it backwards
1. The magnetron includes 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 screw(1) securing the assy 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(1)
Cover Air
Magnetron Fan Motor
SCREW

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 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
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 ceramic 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
SCREW
SCREW
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 pointing tabs are not bent or
broken.
GRILL
HEATER
SCREW
PLATE SPRING
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.
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
Disassembly and Reassembly
Screw¥L Screw¥M
Gas sensor
Screw

4-6 Samsung Electronics
1. Remove two screw from the back cover.
2. Disconnect all lead wires from the oven motor.
3. Remove form screw form the oven motor
assembly.
4. Adjustment or exchange.
5. Reconnect all the lead wires.
1. Remove screw(1) securing the sensor
thermister.
2. Disconnect all lead wires from the mian wire.
4-13 Replacement of Back cover and Oven motor assembly
4-14 Replacement of Sensor Thermister
Disassembly and Reassembly
SCREW Sensor
thermister
Back cover screws
Oven motor Assembly

Samsung Electronics
5. Alignment and Adjustments
5-1 High Voltage Transformer
5-2 Low Voltage Transformer
5-3 Magnetron
5-1
1. Remove connectors from the transformer terminals
and check continuity.
2. Normal resistance readings are as follows:
(Room temperature = 20ûC)
1. Continuity checks indicate only an open filament
or a shorted magnetron. To diagnose an open
filament or shorted magnetron, do the following:
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.
1. The low voltage transformer is located on the
base plate.
2. Remove the low voltage transformer from the
base plate and check continuity.
3. Normal resistor readings a shown in the table.
PRECAUTION
1. High voltage is present at the high voltage terminals during any cook cycle.
2. Do not attempt to measurement the high voltage.
3. Before touching any oven components or wiring, always unplug the oven and discharge the high voltage capacitor.
Filament Terminals
Secondary
Terminal
Primary
Terminals
MODEL CE1279KSE
Secondary Approx. 96Ω
Filament Approx.0Ω
Primary Approx.1.58Ω
Terminals Resistance
1~2(11V) 0.56Ω
1~3(Input) 77.27Ω
4~5(Output 17.5V) 1.39Ω
5~6(Output 7.3V) 0.6Ω
7~8(Output 3.2V) 0.61Ω
8~9(Output 2.7V) 0.51Ω
Cooling Fins
Gasket Plate
Magnetron Antenna

Samsung Electronics
5-4 High Voltage Capacitor
5-5 High Voltage Diode
5-6 Main Relay and Power Control Relay
5-7 Adjustment of Primary Switch, Door Sensing Switch and Monitor Switch
5-2
1. Check continuity of the capacitor with the meter set at the highest resistance scale.
2. Once the capacitor is charged, a normal capacitor shows continuity for a short time, and then indicates 9MΩ.
3. Shorted capacitor indication: continuity.
4. Open capacitor noication constant 9MΩ.
5. Resistance between each terminal and chassis should read infinite.
1. Isolate the diode from the circuit by disconnecting its leads.
2. With the ohm-meter set at the highest resistance scale, measure 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 KΩin the reverse direction.
1. When mounting primary switch and interlock
monitor switch to latch body, consult the figure.
2. No specific adjustment is necessary 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 the Latch Body by moving it so
that the oven door has vo "play". Check for play
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 re-check that
the the monitor circuit and all latch switches are
secured.(see 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.
1. The relays are located on the PCB Ass'y. Isolate them from the main circuit by disconnecting the leads.
2. Operate the microwave oven with a water load. Set the power level to "high"
3. Check continuity between terminals of the relays after the start pad is pressed.
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
(replace 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.
Alignment and Adjustments
Door Open Door Closed
Primary switch ∞0
Monitor switch (COM-NC) 0 ∞
Monitor switch (COM-NO) ∞0
Door Sensing S/W ∞0
Primary Interlock Switch
Lever Door(B)
Body Latch
Door Sensing
Switch
Guide switch
Interlock Monitor
Switch

Samsung Electronics 5-3
The output power of the magnetron can be measured by performing a water temperature rise test.
Equipment needed :
* One 1-liter cylindrical borosilicate glass vessel (Outside diameter 190 mm)
* One glass thermometer with mercury column
NOTE: Check line voltage under load. Low voltage will lower the magnetron output. Brenk the line here
make all temperature and time tests with accurate equipment.
1. Fill the one liter glass vessel with water.
2. Stir water in glass vessel with thermometer, and record glass vessel's temperature ("T1", 10±1ûC).
3. After moving the water into another glass vessel, place it in the center of the cooking tray. Set the oven to high
power and operate for 51 seconds exactly. (3 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 ("T2").
5. Subtract T1 from T2. This will give you the water temperature rise. (∆T)
6. The output power is obtained as follows :
* Output (W) = 85.5x ∆T
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 done if temperature rise is marginal.
NOTE 2: Output power in watts is computed by multiplying the temperature rise (step E) by a factor of 91
times the centigrade temperature.
The microwave heat distribution can be checked indirectly by measuring the water temperature rise at
certain positions in the oven:
1. Prepare five beakers made of 'Pyrex', each having 100 milliliters capacity.
2. Measure exactly 100milliliters off water load with a measuring cylinder, and pour into each beaker.
3. Measure the temperature of each water load. (Readings shall be taken to the first decimal.)
4. Put each beaker in place on the cooking tray as illustrated in the figure. Start heating.
5. After heating for 2 minutes, measure the water temperature in each beaker.
6. Microwave heat distribution rate can be calculated as follows:
Minimum
Temperature Rise
Heat Distribution = X 100(%)
Maximum
Temperature Rise
The result should exceed 65%.
4.187 x 1000 x ∆T
Output Power = 49
49 : Heating Time (sec)
4.187 : Coefficient for Water
1000 : Water (cc)
∆T : Temperature Rise (T2-T1)
5-8 Output Power of Magnetron
5-9 Uniformity of Microwave Heat Distribution
Alignment and Adjustments
D
D
D/4
D/4
D/4
D/4
Cooking Tray
Beaker
CAUTION
MICROWAVE RADIATION
DO NOT ALLOW EXPOSURE TO MICROWAVE RADIATION FROM ANY PARTS CONDUCTING MICROWAVE ENERGY.

Samsung Electronics5-4
5-9 Leakage Measuring Procedure
Alignment and Adjustments
5-9-1 Equipment
1. Microwave Energy Survey Meter
2. Glass beaker, 600cc
3 Mercurial or digital thermometer 100ûC or 212ûF
5-9-2 Procedure for Measurement of Microwave Leakage
1. Pour 275±15cc of 20±5ûC (68±9ûF) in toA 600cc graduated beaker. Place the beaker in the center of the
oven.
2. Start the oven and measure the leakage using a microwave energy survey meter.
3. Set survey meter ( 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 on the door seam and move the probe along
the viewing windows and exhaust openings. Move the probe at about 1 inch per second.
If the leakage from door seam is measured near a corner, keep the probe perpendicular, making sure
the probe end(at the base of the cone) does not gt closer than 2 inches to any metal (otherwise,
erroneous readings readings will result).
5. The measured leakage must be less than 5mW/cm2.
WARNING
AVOID TOUC HING THE HIGH VOLTAGE COMPONENTS.

Samsung Electronics 5-5
5-9 Leakage Measuring Procedure
Alignment and Adjustments
5-9-3 Check for Microwave Leakage
( With the opter panel removed)
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 5mW/cm2.
5-9-4 Measurement Notes
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.
5-9-5 Record Keeping and Special Notification
1. After adjustment and repair of a radiation protection device, record for the measured values, and keep
the data.
2. If the radiation leakage exceeds 5mW/cm2(after determining that all parts are in good condition,
functioning properly and that central service center identical parts are replaced as listed in this
manual) notify the central repair facility.
3. At least once a year have the Microwave Energy Survey Meter checked for accuracy by its
manufacturer.

6. Circuit Description
6-1 When food is placed inside oven and door is closed
1. Low voltage transformer supplies the necessary voltage to the touch control circuit when power cord is
plugged in.
2. The primary interlock switch is closed.
3. The interlock monitor switch is opened. This interlock monitor switch blows the 10A fuse and stops
magnetron oscillation when the door is opened (abnormal condition).
4. The door key is caught by the door hook, this clodesthe door sensing switch is closed to send the door-
close signal to the touch control circuit.
6-2 When cooking, power and time are set by touching the function pads
1. The time appears in the display window.
2. The touch control circuit stores the cooking data at.
6-3 When the START pad is touched
1. The main relay and the power control relay are controlled by the touch control circuit.
2. An oven lamp lights the inside of the oven by (The main relay in the Touch Control Circuit).
3. The fan motor rotates and cools the magnetron by blowing the air from the intake (on the back panel)
over the magnetron fins. After cooling the fins, this air is directed into the oven to blow out the vapor.
4. 230V~50Hz AC is applied to the high voltage transformer through the contacts of primary windings (
shown by the solid line) just after the power control relay turns ON. (Fig. 1)
5. 3.4V AC is generated from the filament winding of the high voltage transformer. This 3.4V is applied to
the magnetron to heat the magnetron filament through two noise preventing choke coils.
6. High voltage (2,230 volts AC) is generated by the high voltage transformer secondary. This secondary
voltage is increased by the diode and high voltage capacitor. This resultant DC voltage is then applied
to the anode of the magnetron. As shown in Fig. 2, the first half cycle of the high voltage produced in
the secondary high voltage transformer charges the high voltage capacitor.The dotted lines indicate the
current flow. During operation of the second half cycle, the voltage produced by the transformer
secondary (plus the charge of the high voltage capacitor) is applied to the magnetron as shown in the
solid line, which cawses the magnetron to oscillate. The electrlcal interference generated by the
magnetron is prevented by the 1.6uH choke coils, 500pF filter capacitors and the magnetrons shielded
case (so that TV and radio signals are immune).
7. The power control relay is turned on intermittently by the touch control circuit (when the oven is set at
any power) except full power. The touch control circuit controls the ON/OFF time of the power control
relay in order to vary the output power of the microwave oven from Low to "Full" power. One
complete ON/OFF cycle of the power control is 30 seconds.
8. The cooking when the oven is set at any power setting is shown on the display (starts to count down.)
Power Relay
Primary Switch
Interlock
Monitor
Switch
H.V.Trans
Lamp
L
Main Relay
Monitor Fuse
Magnetron
H.V.
Capacitor
Diode
H.V.
TRANS
Samsung Electronics 6-1

Samsung Electronics6-2
Circuit Description
6-4 When the door is opened during cooking
1. The primary interlock switch is opened to cut off the primary voltage of the high voltage transformer.
Thes stops microwave oscillation.
2. The door sensing switch is opened which signals the touch control circuit. The main relay stays on, the
power control relay turns off and the display stops counting down.
3. The fan motor and turn-table motor are stopped by operation of the primary interlock switch. The oven
lamp lights the inside of the oven again until the door is closed.
4. Upon opening the door, the contacts of the primary interlock switch open and the contacts of interlock
monitor switch close.
5. If the contacts of primary interlock switch do not function properly, the monitor fuse blows out because
of the large current surge (caused by the monitor switch activation, which stops magnetron oscillation).
see Fig. 3
6-5 When the CANCEL pad is touched during cooking
1. Touching the CANCEL pad once stops cooking. Touching on the pad twice cancels all programs stored
in the touch control circuit. The time of day reappears on the display window.
2. The oven lamp and cooking indicators turn off.
3. The fan motor stops.
4. The power control relay turns off to cutting the primary voltage to the high voltage transformer (This
stops magnetron oscillation).
Power Relay
Interlock
Monitor
Switch
H.V.Trans
Main Relay
Primary Switch
Monitor Fuse

7-1-1. Overview
7-1-2. Operation
1. If the weight of the food is less than 1.5Kg (including the cooker), the rotating dish automatically
moves to the optimum location by the elevation motor.
(If the weight is more than 1.5Kg the cooking is done in the basic location)
2. When defrosting, the weight sensor detects the weight and moves the food to the appropriate
height . (The elevation operates when the weight is less thon1.1Kg or less (including the dish)).
3. When reheating food 700g or less (including the dish), it swings once and then cookis in the basic
location. (If the weight is 700g the cooking is done in the basic location)
4. Manual cooking is done in the basic location with only the rotating motor operating.
7-1-3. Operating Principle of the Height Sensor
The weight sensor converts the weight of the food into a series of pulses that are compared to
the"zero point" wavefrom. This frequency difference determines the cooking time.
7. Troubleshooting
7-1Samsung Electronics
7-1 Checking the Weight Sensor
Tantable motor
Elevarion motor
( Output Wave )
The output frequency of the basic condition (when 0
point adjusted) is between 3150 and 3650Hz.
5V
0V
Shaft
Weight sensor