MICROWAVE OVEN TECH SHEET
CAUTION
Disconnect from Electrical Supply Before Servicing Unit
PRECAUTIONS TO BE OBSERVED BEFORE AND
DURING SERVICING TO AVOID PROSSIBLE
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 operating.
2. Proper door closing.
3. Seal and sealing surfaces ( Arcing,
wear and other damage.)
4. Damage to or loosening of hinges
and latch.
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. Waveguide or
transmission line. And cavity for proper
alignment, integrity and connection.
D. Any detective or mis-adjusted
components in the interlock, monitor, door
seal, and microwave generation and
transmission systems shall be repaired.
replaced. or adjusted by producers.
designed 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.
F. Do not attempt to operate the oven if the
door glass is broken.
Parts Layout
Schematic Diagram
Warning : Power must be disconnected before servicing this appliance
Wiring Diagram
Warning : Power must be disconnected before servicing this appliance
NOTE: Door is open
Made in china
MODEL NO. :
NOTE: For servicing replacement use 16GA,105 C thermoplastic covered wire
except for high voltage leads or as noted on special leads.
1
12
RD-5
BR-22
OG-18
GN-23
GY-26
BL-25
BK-24
WH-31
YW-32
BK-17
WH-15
T/TABLE
MOTOR
FAN
MOTOR
WH-16
YW-7
WH-15
OG-18
WH-16
BL-20
YW-6
BK-17
OVEN
LAMP
GN-23
BL-20
YW-19
YW-21
COOKTOP
LAMP
WH-12
BK-10
POWER
RELAY
WH-30
GN-28
YW-29
OG-27
BL-25
VENT
MOTOR
CAVITY
THERMOSTAT
BK-2
BK-1
BK-2
BK-3
MGT
THERMOSTAT
BOTTOM
THERMOSTAT
BK-4
BK-3
GY-26
BK-24
HOOD
THERMOSTATA
OG-27
WH-31
YW-32
DOOR
SENSING
SWITCH
YW-7
YW-6
PRIMARY
SWITCH
BK-4
BK-8
MONITOR
SWITCH
WH-11
WH-9
YW-29
GN-28
MOTOR
CONDENSER
BK
WH
BK
WH
GND
NOISE
FILTER
BK-1
WH-12
OUT IN
BK
WH
POWER
CORD
WH-11
BK-10
WH-9
BK-8
H.V.TRANS
H.V.CAPACITOR
MGT TUBE
FA
F
H.V.DIODE
WH
RD
RD
RD
P C B
PK:PINK
GN:GREEN
BL:BLUE
YW:YELLOW
RD:RED BK:BLACK
GY:GREY
WH:WHITE
OG:ORANGE
BR:BROWN
GROUND
HARNESS LEADS
PARTS LEADS
OVEN
THERMOSTAT
VENT MOTOR
MOTOR
CONDENSER
NOISE FILTER
OVEN LAMP
H.V.CAPACITOR
MAGNETRON
H.V.TRANSFORMER
FAN MOTOR
HOOD THERMOSTAT
BOTTOM
THERMOSTAT
PRIMARY
SWITCH
DOOR
SENSING
SWITCH
MONITOR
SWITCH
COOK TOP
LAMPS
T/TABLE
MOTOR
H.V.DIODE
MAGNETRON
THERMOSTATA
VENT RELAY
HI (RY5)
7
VENT
MOTOR
T.P.
LOW
(RY4)
ON
(RY3)
L.V.T
SUB
RELAY
(RELAY 1)
LAMP RELAY
1
8
HOOD THERMAL
CUT-OUT
(40/70)
9
MOTOR
CAPACITOR
6
COOKTOP
LAMP
L
L
3
4
L
OVEN
LAMP
120V
FAN
MOTOR
FM
120V
TURNTABLE
MOTOR
TTM
12
POWER RELAY
(RELAY 2)
MAGNETRON
H.V.
CAPACITOR
11
F
FA
H.V.
TRANS
H.V.DIODE
22 BR
10 BK
8 BK
7 YW
18 OG
15 WH
16 WH
17 BK
6 YW20 BL
19 YW
21 YW
23 GN
29 YW
28 GN
30 WH
5 RD
26 GY
25 BL
24 BK
32 YW
31 WH
27 OG
SWITCH (BOTTOM)
SENSE
DOOR
CAVITY
THERMAL
CUT-OUT
(1
1
0/0)
MGT THERMAL
CUT-OUT
(1
6
0/
95
)
BOTTOM THERMAL
CUT-OUT
(1
2
0/
0
)
PK:PINK
GN:GREEN
BL:BLUE
YW:YELLOW
RD:RED
BK:BLACK
GY:GREY
WH:WHITE
OG:ORANGE
BR:BROWN
INTERLOCK ( UPPER)
PRIMARY
SINGLE PHASE
POWER SUPPLY :
ONLY
FILTER ASS'Y
FUSE
BK
WH
GN
GN
1 BK
2 BK
3 BK
4 BK
CONTROL P.W.B. ASS'Y
12 WH
11 WH
9 WH
MONITOR
INTERLOOK
SWITCH
3. Measure resistance .( ohm meter scale: Rx1000)
Filament winding
Primary winding to ground
Primary winding
Secondary winding
Transformer
from the outlet before removing the
Disconnect the power supply cord
7. Normal temperature rise for this model is 9.9 C to 10.3 C at ‘HIGH’.
NOTE 1: Variations or errors in the test procedure will cause a variance in the temperature rise.
SWITCH
Component tests
Switch Chart
CHECK BY
DOOR
CAUTION MICROWAVE RADIATION
DOOR
CLOSE
Primary
Interlock
Disconnect the wires at the Primary Interlock Switch.
Check from the common terminal
to the normally opened terminal.
_
+
Door sensing
Interlock
Disconnect the wires at the sensing interlock Switch.
Check from the common terminal and
Normally closed terminal
_
+
Monitor
Interlock
Disconnect the wires at the Monitor Switch.
Check from the common terminal and
Normally closed terminal .
+
_
( ) CONTINUITY
( ) NO CONTINUITY
_
+
DOOR
OPEN
L
N
Primary
Interlock
Switch
Door
Sensing
Switch
Monitor
Interlock
Switch
DOOR
CLOSE
L
N
Primary
Interlock
Switch
Door
Sensing
Switch
Monitor
Interlock
Switch
Note: These Diagrams are not intended to show a complete circuit, they represent the position of switches
during “DOOR OPEN” and “DOOR CLOSED”. (continuity checks only)
OUTPUT POWER OF MAGNETRON
PERSONNEL SHOULD NOT ALLOW EXPOSURE TO MICROWAVE RADIATION FROM MICROWAVE
GENERATOR OTHER PARTS CONDUCTING MICROWAVE ENERGY.
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 190 mm)
* 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 water.
2. Stir water in glass vessel with thermometer, and record glass vessel’s temperature (“T1”, 10 1 C).
+
_
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 47 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 by the following formula;
Output = 4.187x1000x T+0.55xMcx(T2-T0)
42
45 : Heating Times (sec)
( 3 seconds included as a holding time
of magnetron oscillation.)
4.187 : Coefficient for water
1000 : Water ( cc )
T : Temperature Rise (T2-T1)
T0 : Room Temperature
Mc : Cylindrical borosilicate glass weight
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 5) by a factor
of 91 times the of centigrade temperature.
WARNING
Personal injury/Product Hazard
outer cabinet from the unit.
Discharge the high voltage capacitor
and remove the lead wires from
The primary winding of the high voltage
transformer before conducting any of
the following tests.
Conduct all operation tests with 1 liter
of water in the oven.
Conduct a microwave energy test
after performing any test or repairs
to the microwave.
Check that all wire leads are in the
Correct position before operating
The microwave oven.
Grasp wire connectors when
removing the wire leads from
microwave parts.
Failure to follow these instructions may
result in electrical shock or other
Personal injury or in product damage.
High voltage components
Components
Secondary
Terminal
Filament
Terminals
Primary
Terminal
Magnetron
Cooling
Fins
Capacitor
Diode
Some inexpensive
Meters may indicate
Infinite resistance in
both directions
Ventilation Motor
Test
1. Remove wire leads.
2. Measure resistance .( ohm meter scale: Rx1)
Filament winding to ground
1. Remove wire leads. Install the magnetron seal in the
correct position .Check that the seal is in good condition.
2. Measure resistance .( ohm meter scale: Rx1)
Filament winding
3. Measure resistance .( ohm meter scale: Rx1000)
Filament to chassis
1. Remove wire leads.
2. Measure resistance .( ohm meter scale: Rx1000)
Terminal to terminal
Terminal to case
1. Measure continuity. Forward .( ohm meter scale: Rx1000)
2. Measure continuity. Reverse .( ohm meter scale: Rx1000)
1. Remove wire leads.
2. Measure resistance .( ohm meter scale: Rx1)
2 level: White and Blue wire
Results
Approx. 0.334+2% ohm.
Approx. 118.7+2% ohm.
0 ohm..
Normal: Infinite.
Normal: Infinite.
Normal: Less than 1 ohm
Normal: Infinite.
Normal:
Momentarily indicates several
ohm, and then gradually
returns to infinite.
Normal: Infinite.
Normal: Continuity.
Abnormal: Infinite.
Normal: Infinite.
Abnormal: Continuity.
Approximately 35.2 ohms
T/Table Motor
Fan Motor
Other component tests
1. Remove wire leads.
2. Measure resistance. ( ohm meter scale:
Rx1000)
Normal:
Approximately: 3.3k ohms
1. Remove wire leads.
2. Measure resistance. ( ohm meter scale:
Rx1)
Normal:
Approximately: 97.4 ohms
MODEL NO. :
F
M
V
1 5 2 K
F
M
V
1 5 2 K
p/n 316495069