Sharp R-4A52

R -4A52
R-4E52
TEST PROCEDURES (CONT’D)
PROCEDURE
LETTER COMPONENT TEST
H
TEMPERATURE FUSE OR THERMAL CUT OUT TEST
CARRY OUT 3D CHECKS
Disconnect the leads from the terminals of the temp. fuse or thermal cut-out. Then using an
ohmmeter, make a continuity test across the each two terminals as described in the table below.
CARRY OUT 4R CHECKS
Table: Temperature Fuse Test
Parts F-ame
Temperature of Temperature of Indication of
“ON” condition . “OFF” condition ohmmeter
(closed circuit).
(open circuit). (When room
(“Cl
(“Cl
temperature is
approx. 20°C.)
Temp. fuse 1 50°C
(Magnetron)
Thermal cut-out
145°C (Oven)
This is not resetable
Above 1 50°C Closed circuit
type.
- 20°C
Above 145’C Closed circuit
If incorrect readings are obtained, replace the temp. fuse or thermal cut-out.
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 thermal cut-out (OVEN) indicates that the foods in the oven catch fire, this may
be due to over heating produced by unproper setting of the cooking timer or failure of the control
panel.
MOTOR WINDING TEST
CARRY OUT 30 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
1 Motors
I
Resistance
i F an motor
1 Approximately 246f2
1 Turntable motor
1 Approximately 12.5kn
If incorrect readings are obtained, replace the motor. (Also refer to test procedure J)
CARRY OUT 4R CHECKS
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