Sharp Carousel R-350J, Service Manual

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R-350J
10
G MOTOR WINDING TEST
H BLOWN FUSE F10A
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
C. A normal capacitor shows continuity for a short time (kick) and then a resistance of about 10M
Ω
after it has
been charged.
D. A short-circuited capacitor shows continuity all the time.
E. An open capacitor constantly shows a resistance about 10 M
Ω
because of its internal 10M
Ω
resistance.
F. When the internal wire is opened in the high voltage capacitor shows an infinite resistance.
G. The resistance across all the terminals and the chassis must be infinite when the capacitor is normal.
If incorrect reading are obtained, the high voltage capacitor must be replaced.
CARRY OUT 4R CHECKS.
E SWITCH TEST
CARRY OUT 3D CHECKS.
Isolate the switch to be tested and using an ohmmeter check between the terminals as described in the following
table.
Table: Terminal Connection of Switch
Plunger Operation COM to NO COM to NC COM; Common terminal
Released Open circuit Short circuit NO; Normally open terminal
Depressed Short circuit Open circuit NC; Normally close terminal
If incorrect readings are obtained, make the necessary switch adjustment or replace the switch.
CARRY OUT 4R CHECKS.
CARRY OUT 3D CHECKS.
Disconnect the leads from the terminals of the temperature fuse. Then using an ohmmeter, make a continuity
test across the two terminals as described in the table below.
CARRY OUT 4R CHECKS.
Table: Temperature fuse Test
Temperature of "ON" condition Temperature of "OFF" condition Indication of ohmmeter
Parts Name (closed circuit) (˚C) (open circuit) (˚C) (When room temperature
is approx. 20˚C)
Temperature fuse 150˚C This is not resetable type. Above 150˚C Closed circuit.
If incorrect readings are obtained, replace the temperature fuse.
An open circuit temperature fuse (MG) indicates that the magnetron has overheated, this may be due to
resistricted ventilation, cooling fan failure or a fault condition within the magnetron or HV circuit.
An open circuit temperature fuse (OVEN) indicates that the foods in the oven may catch fire, this may be due
to over heating produced by improper setting of the cooking time or failure of the control panel.
F TEMPERATURE FUSE TEST
CARRY OUT 3D CHECKS.
Disconnect the leads from the motor.
Using an ohmmeter, check the resistance between the two terminals as described in the table below.
Table: Resistance of Motor
Motors Resistance
Fan motor Approximately 250
Ω
Turntable motor Approximately 14.5 k
Ω
If incorrect readings are obtained, replace the motor.
CARRY OUT 4R CHECKS
CARRY OUT 3D CHECKS.
1. If the fuse F10A is blown, there could be shorts or ground in electrical parts or wire harness.
Check them and replace the defective parts or repair the wire harness.