R-8740 (serv.man12). Test data and Wiring rewiring — Sharp Home Appliance Service Manual (repair manual)

Model
R-8740 (serv.man12)
Pages
1 Few pages! See other manuals at the bottom of the first or last page.
Size
438.23 KB
Type
PDF
Document
Service Manual
Brand
Device
Home Appliance / Microwave Oven / Test data and Wiring rewiring
File
r-8740-sm12.pdf
Date

View Sharp R-8740 (serv.man12) Service Manual online

R-8740M  - 34
TEST DATA AT A GLANCE
Parts
Symbol
Value / Data
Fuse
F1
20A 250V
Fuse
F2
F8A  250V
Thermal cut-out
TC1
150˚C
Thermal cut-out
TC2
125˚C
Thermistor
Approx. 326 kΩ - 175 kΩ at 20˚C - 30˚C
Top grill heating element
GH
Approx. 22 Ω. x 2 = 44 Ω
Insulation resistance > 10MΩ
Bottom grill heating element
CH
Approx. 66Ω
Insulation resistance > 10MΩ
Oven lamp
OL
240 - 250 V   25W   E14
High voltage capacitor
C
1.07µF   AC 2100V
Magnetron
MG
Filament < 1Ω
Filament - chassis ∞ ohm.
High voltage transformer
T
Filament winding   < 1Ω.
Secondary winding Approx. 122Ω.
Primary winding Approx. 1.9Ω
Resistance (Disconnect the
In/Out put terminal
Test Point
Volt
power and door is closed)
Input terminal (Power supply)
A9 - A11
230V
Approx. 486 Ω
Input terminal (Stop switch)
B1 - B2
-
0
Input terminal (Thermistor)
C1 - C3
DC. 5V
Approx. 194 kΩ at 20˚C - 30˚C
Output terminal (Top grill heating element)
N.O of RY3 - A9
230V
Approx. 510 Ω
Output terminal (Bottom grill heating element)
N.O of RY4 - A9
230V
Approx. 534 Ω
Output terminal (Fan motor)
A9 - A5
230V
Approx. 875 Ω
Output terminal (Turntable motor and Oven lamp) A3 - N.O. OF RY1
230V
Approx. 186 Ω
Output terminal (Convection fan motor)
A9 - A7
230V
Approx. 223 Ω
Output terminal (Earth)
B2 - Chassis
-
0
TEST POINTS ON CONTROL UNIT
WARNING: DISCONNECT THE PLUG WHEN MEASURING RESISTANCE.
WARNING: WIRING / RE-WIRING.
Before carrying out any work; carry out 3D checks.
1. Disconnect the supply
2. Open the door and wedge open.
3. Discharge the high voltage capacitor.
RE-WIRING.
Ensure the following:
1. Wires must not touch:
a) High voltage parts.
(Magnetron, high voltage transformer, high
voltage capacitor and high voltage rectifier).
b) Parts that become hot.
(Heating elements, oven lamp, oven cavity
magnetron and high voltage transformer).
c) Sharp edges.
(Bottom plates, oven cavity, waveguide
flange, chassis support and other
metallic parts).
d) Movable parts.
( Fan blade, any motor, switch).
2. Positive lock connectors are fitted correctly.  Ensure
the locking pin is located correctly.
3. Wires are connected correctly as per pictorial
diagram.
4. No wire leads are trapped by the outer wrap.
WIRING/RE-WIRING
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Download Sharp R-8740 (serv.man12) Service Manual (Repair Manual)

Here you can view online or download Sharp R-8740 (serv.man12) Service Manual in pdf. This Service Manual can help you recover, restore, fix, disassemble and repair Sharp R-8740 (serv.man12) Microwave Oven. Information contained in Sharp R-8740 (serv.man12) service manual (repair manual) typically includes:

  • Disassembly, troubleshooting, programming, maintenance, remote, adjustment, installation and setup instructions.
  • Schematics, wiring and block diagrams.
  • Printed wiring boards (PWB) and printed circuit boards (PCB).
  • Parts list (bill of materials).