8. PROCEDURE FOR MEASURING MICROWAVE
ENERGY LEAKAGE
A. CAUTIONS
(1) Be sure to check a microwave emission prior to servicing
the oven if the oven is operative prior to servicing.
(2) The service personnel should inform the manufacturer,
importer, or assembler of any certified oven unit found to
have a microwave emission level in excess of
5mW/cm.sq. and should repair any unit found to have
excessive emission levels at no cost to the owner and
should ascertain the cause of the excessive leakage.
The service personnel should instruct the owner not to
use the unit until the oven has been brought into
compliance.
(3) If the oven operates with the door open, the service
personnel should;
- Tell the user not to operate the oven
- Contact the manufacturer and CDRH (Center for
Devices and Radiological Health) immediately.
NOTE: Address on CDRH
Office of Compliance (HFZ-312)
Center for Devices and Radiological Health
1390 Piccard Drive
Rockville, Maryland 20850
(4) The service personnel should check all surface and vent
openings for microwave emission testing.
(5) Check for microwave energy leakage after every
servicing. The power density of the microwave radiation
leakage emitted by the microwave oven should not
exceed 1mW/cm.sq. And always start measuring of an
unknown field to assure safety for operating personnel
from radiation leakage.
NOTE: The standard is 5mW/cm.sq. while in the
customer’s home. 1mW/cm.sq. stated here is
manufacturer’s own voluntary standard for units in
customer’s home.
EQUIPMENT
• Electromagnetic energy leakage monitor (NARDA 8100B,
HOLADAY HI 1501)
• 600cc glass beaker
• Glass thermometer 100°C
B. MEASURING MICROWAVE ENERGY LEAKAGE
(1) Pour 275
±
15cc of 20
±
5°C water in a beaker which is
graduated to 600 cc, and place the beaker in the center
of the oven.
(2) Set the energy leakage monitor to 2,450 MHz and use it
following the manufacturer’s recommended test
procedure to assure correct result.
(3) When measuring the leakage, always use the 2 inch
(5cm) spacer supplied with the probe.
(4) Operate the oven at its maximum output.
(5) Measure the microwave radiation using and
electromagnetic radiation monitor by holding the probe
perpendicular to the surface being measured. (See
Figure 6)
C. MEASUREMENT WITH THE OUTER CASE REMOVED
(1) When you replace the magnetron, measure for
microwave energy leakage before the outer case is
installed and after all necessary components are
replaced or adjusted. Special care should be taken in
measuring the following parts.
- Around the magnetron
- The waveguide
WARNING: AVOID CONTACTING ANY HIGH VOLTAGE
PARTS.
-12-
Move probe along shaded area.
Probe scanning speed
less than 2.5 cm/sec.
Figure 6
Figure 5
Содержание LTM9020B
Страница 34: ... 33 13536A 13552A 13213A 13581A 14890A 14970A 14026A 15006A 268712 13581S WTP004 23506A 13720D DOOR PARTS ...
Страница 35: ... 34 WTP013 35889A 34370T 36549S 33390G WTT010 WTT020 WSZ185 33052A 33112U OVEN CAVITY PARTS ...
Страница 36: ... 35 WSZ085 56912B 55262A 44510A 43500A 466001 466003 466001 43501A LATCH BOARD PARTS ...
Страница 38: ... 37 56170D 63303A WSZ002 WTT021 WTT028 647781 65006A 63302A WTT021 BASE PLATE PARTS ...
Страница 40: ... 43 SCHEMATIC DIAGRAM OF P C B ...
Страница 41: ...PRINTED CIRCUIT BOARD 44 ...
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Страница 43: ...P NO 3828W5S3279 Apr 2003 Printed in Korea ...