DOWNLOAD Sharp R-82STM-A Service Manual ↓ Size: 2.02 MB | Pages: 23 in PDF or view online for FREE

Model
R-82STM-A
Pages
23
Size
2.02 MB
Type
PDF
Document
Service Manual
Brand
Device
Home Appliance / Microwave Oven / R82STMA (March 2013)
File
r-82stm-a.pdf
Date

Sharp R-82STM-A Service Manual ▷ View online

 
 
 
CAUTIONS 
 
 
 
 
• DO NOT operate on a 2-wire extension cord during 
repair and use. 
• NEVER TOUCH any oven components or wiring during 
operation. 
• BEFORE TOUCHING any parts of the oven, always 
remove the power plug from the outlet.   
• For about 30 seconds after the oven stops, an electric 
charge remains in the high voltage capacitor. When 
replacing or checking, you must discharge the high 
voltage capacitor by shorting across the two terminals 
with an insulated screwdriver. 
 
 
 
• Remove your watches whenever working close to or 
replacing the Magnetron. 
• DO NOT touch any parts of the control panel circuit. A 
resulting static electric discharge may damage this 
P.C.B.  
• NEVER operate the oven with no load. 
• NEVER injure the door seal and front plate of the oven 
cavity. 
• NEVER put iron tools on the magnetron. 
• NEVER put anything into the latch hole and the 
interlock switches area.` 
 
 
 
 
 
 
 
Unlike other appliances, the microwave oven 
is 
high-voltage and high-current equipment. 
Though it is free from danger in ordinary use,
extreme care should be taken during repair. 
MICROWAVE RADIATION 
Personnel should not be exposed to the 
microwave energy which may radiate from the 
magnetron or other microwave generating 
device if it is improperly used or connection. 
All input and output microwave connections, 
waveguide, flange and gasket must be secure 
never operate the device without a microwave 
energy absorbing load attached. 
Never look into an open waveguide or antenna 
while the device is energized. 
• Proper operation of the microwave oven 
requires that 
the magnetron be assembled to the waveguide 
and 
cavity. Never operate the magnetron unless it is
properly installed.   
• Be sure that the magnetron gasket is 
properly 
installed around the dome of the tube 
whenever 
installing the magnetron. 
 
THE OVEN IS TO BE SERVICED 
ONLY 
BY PROPERLY QUALIFIED SERVICE
PERSONNEL.
 
1-1 
 
 
 
THE HEATING PRINCIPLE OF MICROWAVE 
Microwave is one kind of radio wave whose wave length is very short, frequency is very high. Therefore, it is called ultrahigh 
frequency electromagnetic wave. Microwave can heat food mainly result in the mutual affect of the food in the microwave field and 
microwave field itself. 
Under the affect of microwave field, the thermal effect mechanism produced from the mutual affect of the microwave and the food 
includes two aspects: One is Dielectric loss of polar molecule, the other is conductive loss of ion. 
Usually, food is constitute of organism (plant and animal).The organism is formed by all kinds of polar water molecule, polar 
protein molecule, and all sorts of salt ion. The center of gravity of the positive and negative charge in the molecule is not coincide. 
In normal condition, the molecule is in irregular order due to its thermal action, thus the food do not appear polarity (FIG.1-
1a).Under the action of outer electric field, the positive end of the polar molecule trend to the negative electric field, the negative 
end of polar molecule trend to the positive electric field, and somewhat arrange in order through the direction of the electric 
field(FIG.1-1c).This phenomenon usually be called “TORQUE POLARITY”. When the outer electric field apply for the opposite 
polarity, the polar molecule then arrange an opposite direction order accordingly (FIG.1-1b).If the direction of the outer electric field 
changed repeatedly, the polar molecule would repeatedly sway accordingly. During the swaying, it understands that the polar 
molecule would produce heat due to somewhat similar friction among them.   
 
 
 
 
 
 
 
 
When the electric field is applied for ultrahigh frequent microwave field from the outside, its direction would change tens billion 
times per second, so do the molecule. This kind of molecule swaying producing similar frictional heat from the interference and 
block of the action strength among the molecule, and changed to microscopic microwave heating. Microwave heating not only 
concerned the nature of the matter itself, but also closely connected with the electric field strength and frequency. When the 
frequency is low, the molecule swaying rate and the acute degree of the mutual friction among the molecule is low, and would 
produce much heat. When the frequency is too high, as the swing of the polar molecule is with rotating inertia, it made the swing 
do not in line with the changing rhythm of the electric field because of the friction drag, thus, actually lowed the polar molecule 
swaying speed. The friction dragging degree is concerning about the magneto electric wave frequency, polar molecule shape, and 
the matter’s sticky degree. To different matter’s molecule, there are different special frequency zone. Those ado
 
absorb microwave 
energy from these zone are most capable to turn microwave energy to heat energy. 
Apart from the above said action, there is another action which is electric ion under the action of microwave field, act fiercely 
accompanied with the acceleration of electric field. The positive ion transfer to the negative polarity of the field while the negative 
ion do opposite. Accompanying with the changing electric field, the electric ion changing accordingly. During the transferring, heat 
produced with the crash among the ion. This kind of action take the main effect to those microwave heating of high salt molecule. 
No matter it is the polar molecule swaying or the ion transferring, they both are turning the microwave energy which the heating 
matter got from the microwave field to hear energy. From the analysis of theory, we can draw such a conclusion that the power 
which a unit of volume matter absorbed from the microwave field as the following formula: 
Pa=K·E· F·Er·tgδ 
Pa Stands for the power the heated matter absorbed from the microwave field.
 
K Stands for a constant 
E Stand for microwave field strength 
F Stands for the microwave frequency. 
Er Stands for relative dielectric constant of the heated matter.
 
tgδStands for loss angle tangent of the heated matter 
2-1
 
 
 
INSTALLATIONS 
 
INSTALLING 
1. Empty the microwave oven and clean inside it with 
a soft, damp cloth. Check for damage such as 
misaligned door, damage around the door or dents 
inside the cavity or on the exterior. 
 
2. Put the oven on a counter, table, or shelf that is 
strong enough to hold the oven and the food and 
utensils you put in it. (The control panel side of the 
oven is the heavy side. Use care when handling.) 
 
3. Do not block the vent and the air intake openings. 
Blocking vent or air intake openings can cause 
damage to the oven and poor cooking results. 
Make sure the microwave oven legs are in place to 
ensure proper air flow. 
 
4. The oven should not be installed in any area where 
heat and steam are generated, because they may 
damage the electronic or mechanical parts of the 
unit. 
Do not install the oven next to a conventional 
surface unit or above a conventional wall oven. 
 
5. Use microwave oven in an ambient temperature 
less than 104°F(40°C). 
 
6. Place the microwave oven on a sturdy and flat 
surface at least 10 cm(4 inches) from the wall. 
 
7. Place the microwave oven as far away as possible 
from TV, RADIO, COMPUTER, etc., to prevent 
interference. 
 
 
BEFORE YOU BEGIN, READ THE FOLLOWING INSTRUCTIONS COMPLETELY 
EARTHING INSTRUCTIONS 
This microwave oven is designed to be used in a fully 
earthed condition. 
It is imperative, therefore, to make sure it is properly 
earthed before servicing 
WARNING-   
THIS  APPLIANCE 
MUST BE EARTHED 
IMPORTANT
 
 
The wires in this mains lead are colored in 
accordance with the following code: 
Green-and-yellow:              Earth 
Blue:                                      Neutral 
Brown:                                  Live
 
As the colors of the wires in the mains lead of this 
appliance may not correspond with the colored 
markings identifying the terminals in your plug, 
proceed as follows. 
 
The wire which is colored 
green-and-yellow must be 
connected to the terminal in the plug which is marked 
with the letter 
or by the earth symbol (
 ) or 
colored 
green or green-and-yellow
 
The wire which is colored 
blue must be connected to 
the terminal in the plug which is marked with the letter 
or colored black
 
The wire which is colored 
brown must be connected 
to the terminal in the plug which is marked with the 
letter 
or colored red
3-1 
SCHEMATIC DIAGRAM
HIGH VOLTAGE TRANSFOMER
SECONDARY
1
2
1
 TM  : TRAY MOTOR
FM  : FAN  MOTOR
OL  : OVEN LAMP
CM  : CONVECTION FAN MOTOR
CONDITION
DOOR  : CLOSED
COOK
[
INTERLOCK
SWITCH
: OFF
]
BL
NOTE :
BL
CN1
CN2
BL
5
3
WH
YW
7
MOTOR
RELAY
WH
BL
FILTER ASS'Y
FUSE
BL
N
GE
N
SINGLE PHASE  
POWER SUPPLY :
ONLY
BR
L
L
WH
GE
N
L
BR
OL
YW
FM
YW
 TM
SWITCH (UPPER)
RD
BR
PRIMARY INTERLOCK
WH
RD
GE  : GREEN/YELLOW
YW  : YELLOW
BK  : BLACK
RELAY
POWER
WH  : WHITE
RD  : RED
CONTROL P.W.B. ASS'Y
CONVECTION
RELAY
HEATER
FAN
RELAY
WH
TOP
RELAY
HEATER
BR  : BROWN
BL  : BLUE
CN3
CUT-OUT
THERMAL
MAGNETRON
WH
TH
ER
MI
ST
OR
CAPACITOR
H.V.
H.V. DIODE 
CON
VE
CT
ION
 H
EA
TE
R
RD
CM
THERMOSTAT
BR
HEATER
BL
BL
TO
HE
AT
ER
BL
HEATER
THERMOSTAT
RD
BK
BR
INTERLOCK
SWITCH
MONITOR
YW
RD
RD
MAGNETRON 
RD
BR
BR
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Sharp R-82STM-A Service Manual ▷ Download

  • DOWNLOAD Sharp R-82STM-A Service Manual ↓ Size: 2.02 MB | Pages: 23 in PDF or view online for FREE
  • Here you can View online or download the Service Manual for the Sharp R-82STM-A in PDF for free, which will help you to disassemble, recover, fix and repair Sharp R-82STM-A Microwave Oven. Information contained in Sharp R-82STM-A Service Manual (repair manual) includes:
  • Disassembly, troubleshooting, maintenance, adjustment, installation and setup instructions.
  • Schematics, Circuit, Wiring and Block diagrams.
  • Printed wiring boards (PWB) and printed circuit boards (PCB).
  • Exploded View and Parts List.