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28

Grill indicator lights 
but oven does not go into
cook cycle when START
pad is touched.

Temperature in the oven
cavity is lower or higher then
preset.

Defective relay 5 of P.C.B.

Open or loose wire 
connection to the above
components.

Check and repair wiring.

Test procedure relay 5 of
P.C.B.

Open or loose wire 
connection to P.C.B.

Two lead wires (Live,
neutral parts) feeding the
Noise filter are
interchanged. 
At this time, microwave

Interchange live part wire
with neutral part wire 
correctly.

Check and repair wiring.

Defective relay 5 of P.C.B.

Defective grill heater 
element.

Test procedure grill heater.

Test procedure relay 5 of
P.C.B.

●

MAKE SURE THE WIRE LEADS CORRECT POSITION.

●

WHEN REMOVING THE WIRE LEADS FROM THE PARTS, BE SURE TO GRASP THE CONNECTOR,
AND NOT THE WIRES.

●

WHEN REMOVING THE MAGNETRON, BE SURE TO INSTALL THE MAGNETRON GASKET IN THE
CORRECT POSITION AND GOOD CONDITION.

Tools normally used for TV servicing are sufficient.
Standard tools are listed below.

●

Diagonal pliers

●

Long nose pliers

●

Cross head screwdriver

●

Wrench (size 5 mm)

●

Nutdriver (size 5 mm)

●

Adjustable wrench

●

Soldering iron

●

Solder

●

Vinyl insulation tape

●

Polishing cloth

●

Be sure to check a microwave emission prior to
servicing the oven if the oven is operative prior to
servicing.

●

If the oven operates with door open, the service
personnel should;
ÑTell the user not to operate the oven

●

The service personnel should check all surface and
vent openings for microwave emission testing.

●

Check for microwave energy leakage after every
servicing. The power density of the microwave
radiation leakage emitted by the microwave oven
should not exceed 4 mW/cm

2

.

And always start measuring of an unknown field to
assure safety for operating personnel from radiation
leakage.

NOTE: The standard is 5 mW/cm

2

while in the

customerÕs home. 4 mW/cm

2

stated here is

manufacturerÕs own voluntary standard for units in
customerÕs home.

●

Microwave Survey Meter

●

600cc glass beaker

●

Glass thermometer 100¡C

●

TESTER (VOLTS-DC, AC, Multmeter)

●

Microwave survey meter
ÑHoladay H1-1500, Hi-1501
ÑNarda 8100, 8200

●

Inch scale

●

600 cc non conductive material beaker (glass or
plastic), inside diameter: approx. 8.5cm (3

1

/

2

in.)

●

Cylindrical and made of borosilicate glass vessel max.
thickness: 3mm
outside diameter: approx. 190mm
height: approx. 90mm

●

Glass thermometer: 100¡C or 212¡F (1 deg scale)

●

Pour 275 ± 15cc of 20¡C ± 5¡C water in a beaker
which is graduated to 600 cc, and place the beaker on
the center of the turntable.

●

Set the energy leakage monitor to 2,450 MHz and use
it following the manufacturerÕs recommended test
procedure to assure correct result.

●

When measuring the leakage, always use the 2 inch
(5cm) spacer supplied with the probe.

●

Operate the oven at its maximum output.

●

Measure the microwave radiation using and
electromagnetic radiation monitor by holding the probe
perpendicular to the surface being measured.

11

Move probe along shaded area.

Probe scanning speed;
Less than 2.5 cm/sec

●

When you replace the magnetron, measure microwave
energy leakage before the out case is installed and
after all necessary components are replaced or
adjusted.
Special care should be taken in measuring the
following parts. (Shaded area of below Fig.)
Ñ Around the magnetron
Ñ The waveguide

●

After all components, including the outer case, are fully
assembled, measure for microwave energy leakage
around the door viewing window, the exhaust opening
and air inlet openings.

●

Microwave energy leakage must not exceed the values
prescribed below.

NOTES:
Leakage with the outer case removed - less than 
5 mW/cm

2

.

Leakage for a fully assembled oven (ÒBefore the latch
switch (primary) is interruptedÓ) with the door in a slightly
opened position - less than 4 mW/cm

2

.

●

Do not exceed meter full scale deflection.

●

The test probe must be removed no faster than, 
1 inch/sec (2.5 cm/sec) along the shaded area,
otherwise a false reading may result.

●

The test probe must be held with the grip portion of the
handle.
A false reading may result if the operatorÕs hand is
between the handle and the probe.

●

When testing near a corner of the door, keep the probe
perpendicular to the surface making sure the probe
horizontally along the oven surface, this may possibly
cause probe damage.

●

After adjustment and repair of any microwave energy
interruption or microwave energy blocking
device, record the measured values for future
reference. Also enter the information on the service
invoice.

●

Should the microwave energy leakage not be more
than 4 mW/cm

2

after determining that all parts are in

good condition, functioning properly and genuine
replacement parts which are listed in this manual have
been used.

●

At least once a year, have the electromagnetic energy
leakage monitor checked for calibration by its
manufacture.

12

●

Microwave power output measurement is made with
the microwave oven supplied at its rated voltage and
operated at its maximum microwave power setting with
a load of (1000 ± 5)g potable water.

● 

The water is contained in a cylindrical borosilicate
glass vessel having a maximum material thickness of
3 mm and an outside diameter of approximately 190
mm.

●

The oven and the empty vessel are at ambient
temperature prior to the start of the test.

●

The initial temperature (±1) of the water is (10±2)¡C. It
is measured immediately before the water is added to
the vessel. After addition of the water to the vessel, the
load is immediately placed on the center of the shelf
which is in the lowest position and the microwave
power switched on.

●  

The time T for the temperature of the water to rise by a
value 

∆

T of (10±2)¡K is measured, where T is the time

in seconds and 

∆

T is the temperature rise. The initial

and final water temperatures are selected so that the
maximum difference between the final water
temperature and the ambient temperature is 5¡K.

1) Disconnect power supply cord from the outlet.
2) Remove the screws from the rear and side section. 

The out case must be moved backward to the lifted off.

1) Remove the out case.
2) Disconnect two terminals from the noise filter assy

and remove one screw of the earth terminal.

CAUTION: DISCHARGE HIGH VOLTAGE

CAPACITOR BEFORE SERVICING
(refer to page 5)

1) Remove screws of the oven hinge plate-L.

2) Open door and remove door assembly from hinge

plate-U.

1. After replacing the door, be sure to check that the

primary switch, monitor switch and secondary switch
operates normally.

●

The microwave power output P in watts is calculated
from the following formula:

P =

is measured while the microwave generator is
operating at full power. Magnetron filament heat-up
time is not included. (about 2 sec.)

●

The water is stirred, to equalize temperature
throughout the vessel, prior to measuring the final
water temperature.

● 

Stirring devices and measuring instruments are
selected in order to minimize addition or removal of
heat.

2. After replacing the door, check for microwave energy

leakage with a survey meter.
Microwave energy must be below the limit of
4mW/cm

2

.,(With a 275ml water load).

13

Water Load

Turn Table

HINGE PLATE-U

HINGE PLATE-L

4187✕(

∆

T

)

T