R-4G75M (serv.man4). Section 3 Component replacement and adjustment procedure, MWO measurement (page 23-29) - Sharp Home Appliance Service Manual (repair manual). Page 6

28

After adjustment of door latch switches, monitor switch and
door are completed individually or collectively, the following
leakage test must be performed with a survey instrument and
it must be confirmed that the result meets the requirements
of the performance standard for microwave oven.

REQUIREMENT
The safety switch must prevent microwave radiation emis-
sion in excess of 5mW/cm2 at any point 5cm or more from
external surface of the oven.

PREPARATION FOR TESTING:
Before beginning the actual test for leakage, proceed as
follows;
1. Make sure that the test instrument is operating normally

as specified in its instruction booklet.
Important:
Survey instruments that comply with the requirement for
instrumentations as prescribed by the performance
standard for microwave ovens must be used for testing.

Recommended instruments are:
NARDA 8100
NARDA 8200
HOLADAY HI 1500
SIMPSON 380M

2. Place the oven tray into the oven cavity.
3. Place the load of 275 

±

 15ml of water initially at 20 

±

 5

°

C

in the center of the oven tray. The water container should
be a low form of 600 ml beaker with inside diameter of
approx. 8.5cm and made of an electrically non-conductive
material such as glass or plastic.
The placing of this standard load in the oven is important
not only to protect the oven, but also to insure that any
leakage is measured accurately.

4. Close the door and turn the oven ON with the timer set for

several minutes. If the water begins to boil before the
survey is completed, replace it with 275ml of cool water.

5. Move the probe slowly (not faster that 2.5cm/sec.) along

the gap.

6. The microwave radiation emission should be measured

at any point of 5cm or more from the external surface of
the oven.