LG MH-794GS, Руководство по обслуживанию

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NECESSARY TOOLS
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
CAUTIONS
❥
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 per-
sonnel should;
—Tell 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/cm2.
And always start measuring of an unknown field to
assure safety for operating personnel from radiation
leakage.
NOTE: The standard is 5 mW/cm2 while in the
customer’s home. 4 mW/cm2 stated here is
manufacturer’s own voluntary standard for units in
customer’s home.
EQUIPMENT
❥
Microwave Survey Meter
❥
600cc glass beaker
❥
Glass thermometer 100°C
NECESSARY MEASURING
INSTRUMENTS
• TESTER (VOLTS-DC, AC, Multmeter)
• Microwave survey meter
—Holaday H1-1500, Hi-1501
—Narda 8100, 8200
• Inch scale
• 600 cc non conductive material beaker (glass or
plastic), inside diameter: approx. 8.5cm (31/2 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)
MEASURING MICROWAVE ENERGY
LEAKAGE
❥
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 manufacturer’s 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 elec
tromagnetic radiation monitor by holding the probe per-
pendicular to the surface being measured.
SERVICE INFORMATION
Tools and Measuring Instruments
Microwave Leakage Test
13
Move probe along shaded area.
Probe scanning speed;
Less than 2.5 cm/sec