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5-8 Procedure for Measurement of Microwave Energy Leakage
1) Pour 275±15cc of 20±5° C(68±9° F) water in a beaker
which is graduated to 600cc, and place the beaker in
the center of the oven.
2) Start to operate the oven and measure the leakage by
using a microwave energy survey meter.
3) Set survey meter with 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 of the probe on the door and/or cabinet door
seam and move along the seam, the door viewing
window and the exhaust openings moving the
probe in a clockwise direction at a rate of 1 inch/sec. If the leakage testing of the cabinet door seam is
taken near a corner of the door, keep the probe perpendicular to the areas making sure that the probe end
at the base of the cone does not get closer than 5cm to any metal. If it gets closer than 5cm, erroneous
readings may result.
5) Measured leakage must be less than 4mW/cm
2
, after repair or adjustment.
5-9 Check for Microwave Leakage
1. Remove the outer panel.
2. Pour 275±15cc of 20±5° C(68±9° F) 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 near 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 reading should be less than 4mW/cm
2
.
5-10 Note on Measurement
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.
5-11 Leakage Measuring Procedure
5-11-1 Record keeping and notification after measurement
1) After adjustment and repair of a radiation preventing device, make a repair record for the measured
values, and keep the data.
2) If the radiation leakage is more than 4mW/cm
2
after determining that all parts are in good condition,
functioning properly and the identical parts are replaced as listed in this manual notify that fact to ;
CENTRAL SERVICE CENTER
5-11-2 At least once a year have the microwave energy survey meter checked for accuracy by its
manufacturer.
Maximum allowable leakage is 5mW/cm
2
.
4mW/cm
2
is used to allow for measurement and meter accuracy