18
If the transformer is normal, then the high voltage capacitor should be checked. Pull out the connecting plug of
the capacitor, and measure it with R×1 grade of an avometer, the two rods of the avometer connect the two
polarity of the capacitor. When they just connected, the reading of the avometer should be zero, then increases to
nine megaohm slowly. Change the rod to different polarity, the reading repeat from zero to nine megaohm (FIG.5
- 11), it means the capacitor is normal. If the indicator of the
avometer can’t point out from zero to nine megaohms, it
indicates the high voltage capacitor has broken, and should
be replaced by a new one.
If it is normal between the two pole of the capacitor, then the
insulation between the capacitor pole and the cabinet should
be measured with R×10K grade of an avometer. The
resistance value should be “
∞
” (FIG.5 - 12). If it is short
circuited or have a number reading, it indicates that the
capacitor has been punctured or electricity leaked, and should
be replaced by a same model, same capacity one.
If the resistance value of the capacitor’s two pole are “
∞
”, the capacitor is normal. Then check the earth of the
magnetron’s two filaments to see whether they are short –
circuited (FIG.5 - 13). If they are short – circuited and the
filament strikes the shell of the magnetron, it indicates the
magnetron has broken, and should be replaced by a new,
same model one.
If the magnetron is also normal, then test the pilot switch.
Pull out the two plugs of the switch. Measure it with the R×1
grade of avometer, the two rod connect the plug of the
switch, the resistance value should be “
∞
” (FIG.5 - 8).
Then press down the pilot switch with a screwdriver, if the
reading of the avometer pointed to zero, it indicates the pilot
switch has broken, and should replace it with a new, same
model one.
5
5
.
.
3
3
R
R
E
E
P
P
A
A
I
I
R
R
I
I
N
N
G
G
M
M
E
E
T
T
H
H
O
O
D
D
O
O
F
F
S
S
E
E
V
V
E
E
R
R
A
A
L
L
B
B
R
R
E
E
A
A
K
K
D
D
O
O
W
W
N
N
1. Repair when there occurred large amounts microwave
leakage. There are many factors which may cause microwave
leaking. Following mentioned may be the main causes of
microwave leakage:
(1) The door deformed, the hinge loosed or damaged that
caused the door can not close tightly.
(2) The door pressing cover or the embed piece damaged or
come off.
(3) Obvious damage or uneven of the oven.
(4) There are filth between the door and the oven.
Fig.5-9
Fig.5-10
Fig.5-11
Fig.5-12
magnetron
