Sharp Carousel R-350J, Руководство по обслуживанию

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R-350J
12
M RELAY TEST
N PROCEDURES TO BE TAKEN WHEN THE FOIL PATTERN ON THE PRINTED WIRING BOARD
(PWB) IS OPEN
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
L KEY UNIT TEST
If the display fails to clear when the STOP/CLEAR pad is depressed, first verify the flat ribbon cable is making
good contact, verify that the 2nd. interlock relay control switch operates properly; that is the contacts are closed
when the door is closed and open when the door is open.
If the door 2nd. interlock relay control switch is good, disconnect the flat ribbon cable that connects the key unit
to the control unit and make sure the 2nd. interlock relay control switch is closed (either close the door or short
the 2nd. interlock relay control 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.
CARRY OUT 3D CHECKS.
Remove the outer case and check voltage between Pin No 1 of the 2-pin connector (A) and the normal open
terminal of the relay RY1 on the power unit with an A.C. voltmeter. The meter should indicate 230 - 240 volts,
if not check oven circuit.
RY1 and RY2 Relay 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. 24.0V D.C. Oven lamp / Turntable motor / Cooling fan motor
RY2 APPROX. 23.0V D.C. Power transformer
CARRY OUT 4R CHECKS.
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.
CARRY OUT 3D CHECKS.
STEPS OCCURRENCE CAUSE OR CORRECTION
The rated AC voltage is not present between
1 Pin No. 1 of the 2-pin connector (A) and the Check supply voltage and oven power cord.
normal open terminal of the relay RY1.
2
The rated AC voltage is present to primary Low voltage transformer or secondary circuit defective.
side of low voltage transformer. Check and replace control unit assembly.
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".
5
0
4
9
3
8
2
7
1
6
MORE
LESS
VEGETALIAN
MEALS
HELP
VEGETABLES
EXPRESS
MEAL
REHEAT
MENU
LOW FAT
MEALS
CONVENIENCE
MEALS
POWER
LEVEL
INSTANT COOK
START
RICE/PASTA
EXPRESS
DEFROST
STOP
CLEAR
TIMER
CLOCK
EXPRESS
COOK
EASY
DEFROST
G 1 G 2 G 3 G 4 G 5 G 6 G 7 G 8
G 9
G10
G11
G12
G13
G14