Sharp R-22GT, Руководство по обслуживанию

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18
R-22GV
R-22GT
R-23GT
R-24GT
TEST PROCEDURES (CONT'D)
PROCEDURE
LETTER
COMPONENT TEST
M KEY UNIT TEST
If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon is making good
contact, verify that the door sensing switch (stop switch ) operates properly; that is the contacts are closed
when the door is closed and open when the door is open. If the door sensing switch (stop switch ) is good,
disconnect the flat ribbon cable that connects the key unit to the control unit and make sure the door sensing
switch is closed (either close the door or short the stop switch connector ). Use the key unit matrix indicated
on the control panel schematic and place a jumper wire between the pins that correspond to the STOP/CLEAR
pad making momentary contact. If the control unit responds by clearing with a beep, the key unit is faulty and
must be replaced. If the control unit does not respond, it is faulty and must be replaced. If a specific pad does
not respond, the above method may be used (after clearing the control unit ) to determine if the control unit
or key pad is at fault.
1 3
4
5
6
7
8
9
0
G 8 G 7 G 6 G 5 G 4 G 3 G 2 G 1
G 9
G 10
G 11
G 12
2
DOUBLE
QUANTITY
EXPRESS
DEFROST SELECTA
TIME
STOP /
CLEAR
START SET
CHECK
SIGNAL
1 3
4
5
6
7
8
9
0
G 8 G 7 G 6 G 5 G 4 G 3 G 2 G 1
G 9
G 10
G 11
G 12
2
DOUBLE
QUANTITY
EXPRESS
DEFROST
SELECTA
TIME
STOP /
CLEAR
START SET
CHECK
SIGNAL
SELECTA
POWER
R-22GV R-22GT/R-23GT/R-24GT
N RELAY TEST
Remove the outer case and check voltage between Pin Nos. 3 and 7 of the connector (A) on the control unit
with an A.C. voltmeter. The meter should indicate rated voltage, if not, check oven circuit.
RY1, RY2 and RY3Relay Test
These relays are operated by D.C. voltage.
Check voltage at the relay coil with a D.C. voltmeter during the microwave cooking operation.
DC. voltage indicated ............................... Defective relay.
DC. voltage not indicated ......................... Check diode which is connected to the relay coil. If diode is
good, control unit is defective.
RELAY SYMBOL OPERATIONAL VOLTAGE CONNECTED COMPONENTS
RY1 APPROX. 12.0V D.C. Oven lamps, Blower motor and Stirrer motors
RY2 APPROX. 12.0V D.C. Power transformer 1
RY3 APPROX. 12.0V D.C. Power transformer 2
O PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING BOARD
(PWB) IS OPEN
To protect the electronic circuits, this model is provided with a fine foil pattern added to the primary on the PWB,
this foil pattern acts as a fuse. If the foil pattern is open, follow the troubleshooting guide given below for repair.
Problem: POWER ON, indicator does not light up.
STEPS OCCURANCE CAUSE OR CORRECTION
1 The rated voltage is not applied to POWER Check supply voltage and oven power cord.
terminal of CPU connector (CN-A)
2 The rated voltage is applied to primary side Power transformer or secondary circuit defective.
of power transformer. Check and repair.
3 Only pattern at "a" is broken. *Insert jumper wire J1 and solder.
4 Pattern at "a" and "b" are broken. *Insert the coil RCILF2003YAZZ between "c" and "d".
NOTE: *At the time of making these repairs, make a visual inspection of the varistor. Check for burned