Sharp MMD24B ユーザーズマニュアル

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MMD24S
MMD24B
MICROWAVE MEASUREMENT PROCEDURE  
A.  Requirements:
)  Microwave leakage limit (Power density limit): The power density of microwave radiation emitted by a microwave 
oven should not exceed mW/cm
2
 at any point 5cm or more from the external surface of the oven, measured prior to 
acquisition by a purchaser, and thereafter (through the useful life of the oven), 5 mW/cm
2
 at any point 5cm or more 
from the external surface of the oven. 
2)  Safety interlock switches:
 
Primary interlock relay switch shall prevent microwave radiation emission in excess of the requirement as above
   mentioned. Secondary interlock relay and door sensing switch shall prevent microwave radiation emission in excess 
of 5 mW/cm2 at any point 5cm or more from the external surface of the oven.
B. Preparation for testing:
Before beginning the actual measurement of leakage, proceed as follows:
)  Make sure that the actual instrument is operating normally as specified in its instruction booklet.
 
Important:
Survey instruments that comply with the requirement for instrumentation as prescribed by the performance standard 
for microwave ovens, 2 CFR 030.0(c)(3)(i), must be used for testing. 
Survey instruments that comply with the requirement for instrumentation as prescribed by CSA and NHW performance 
standard for microwave ovens must be used for testing recommended instruments are , NARDA 800 and NARDA 
8200.
2)  Place the load of 275±5 ml (9.8 oz) of tap water initially at 20±5
O
 
C (68
O
F) in the center of the oven cavity.
 
The water container shall be a low form of 600 ml (20 oz) beaker with an inside diameter of approx. 8.5 cm (3-/2 
in.) 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.
3)  Set the cooking control on Full Power Cooking Mode. 
4)  Close the drawer and select a cook cycle of several minutes. If the water begins to boil before the survey is completed, 
replace it with 275 ml of cool water.
C.  Leakage test:
Closed-drawer leakage test (microwave measurement):
)  Grasp the probe of the survey instrument and hold it perpendicular to the gap between the drawer and the body of 
the oven.
2)  Move the probe slowly, not faster than  in./sec. (2.5 cm/sec.) along the gap, watching for the maximum indication 
on the meter.
3)  Check for leakage at the drawer screen, sheet metal seams and other accessible positions where the continuity of 
the metal has been breached (eg., around the switches, indicator, and vents).
 
While testing for leakage around the drawer, pull the drawer away from the front of the oven as far as is permitted 
by the closed latch assembly.
4)  Measure  carefully  at  the  point  of  highest  leakage  and  make  sure  that  the  highest  leakage  is  no  greater  than 
4mW/cm
2
, and that the primary interlock switch/secondary interlock relay does turn the oven OFF before any door 
movement.
NOTE:   After servicing, record data on service invoice and microwave leakage report.