R-64ST - 16
Table: Thermal Cut-out Test
Temperature of "ON"
Temperature of "OFF"
Indication of ohmmeter
Parts Name
condition (closed circuit).
condition (open circuit).
(When room temperature
(˚C)
(˚C)
is approx. 20˚C.)
Oven thermostat 150˚C
This is a resettable type.
Above 150˚C
Closed circuit 130˚C
HVT thermostat 150˚C
This is a resettable type
Above 150˚C
Closed circuit 96˚C.
F
THERMAL CUT-OUT TEST
Table: Resistance of Motor
Motors
Resistance
Fan motor
Approximately 373
Ω
Turntable motor
Approximately 15.5 k
Ω
If incorrect readings are obtained, replace the motor.
CARRY OUT 4R CHECKS.
CARRY OUT 3D CHECKS
Disconnect the leads from the terminals of the thermal cut-out. Then using an ohmmeter, make a continuity
test across the two terminals as described in the below.
G
MOTOR WINDING 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.
H
NOISE FILTER TEST
CARRY OUT 3D CHECKS.
Disconnect the leads from the terminals of
noise filter.
Using an ohmmeter, check between the ter-
minals as described in the following table.
MEASURING POINTS
INDICATION OF OHMMETER
Between N and L
Approx. 680 k
Ω
Between terminal N and WHITE
Short circuit
Between terminal L and RED
Short circuit
If incorrect readings are absorbed, replace the noise filter unit.
CARRY OUT 4R CHECKS.
TEST PROCEDURES
If incorrect readings are obtained, replace the thermal cut-out.
An open circuit thermal cut-out (TX) indicates that the transformer has overheated, this may be due
to restricted ventilation, cooling fan failure.
An open circuit thermal cut-out (OVEN) indicates that the oven cavity has overheated, this may be due
to no load operation, or burning load has occured.
CARRY OUT 4R CHECKS.
PROCEDURE
LETTER
COMPONENT TEST
Cx
Cy
WHT
RED
20A
N
L
Cy
R64ST_S.MANUAL
12/8/01, 11:01 am
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