Sharp R-1501 Microwave Oven User Manual


 
19
R-1500
R-1501
R-1505
R-1506
TEST PROCEDURES
PROCEDURE
LETTER
COMPONENT TEST
1. Disconnect the power supply cord, and then remove outer case. Refer to procedure of " HOOD
EXHAUST LOUVER REMOVAL ", " REMOVAL OF OVEN FROM WALL " and " OUTER CASE
REMOVAL ".
2. Open the door and block it open.
3. To discharge high voltage capacitor, wait for 60 seconds.
4. Remove the hood intake duct R.
5. Disconnect the leads to the primary of the power transformer.
6. Ensure that these leads remain isolated from other components and oven chassis by using insulation
tape.
7. After that procedure, re-connect the power supply cord.
8. Check voltage between normal open terminal of the relay RY2 and the normal open terminal of the
relay RY1 on the control unit with an A.C. voltmeter.
The meter should indicate 120 volts, if not check oven circuit.
RY1, RY2, RY3, RY4, RY5 and RY6 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. 26.6V D.C. Oven lamp / Fan motor / Turntable motor
RY2(COOK) Approx. 26.0V D.C. Power transformer
RY3 Approx. 26.6V D.C. Hood motor
RY4 Approx. 26.6V D.C. Hood motor
RY5 Approx. 26.6V D.C. Hood lamp
RY6 Approx. 26.6V D.C. Hood lamp
9. Disconnect the power supply cord.
10. Open the door and block it open.
11. To discharge high voltage capacitor, wait for 60 seconds.
12. Reconnect all leads removed from components during testing.
13. Re-install the hood intake duct R.
14. Re-install the outer case (cabinet).
15. Reconnect the power supply cord after the outer case is installed.
16. Run the oven and check all functions.
N RELAY TEST
O DEFROST CENTER TEST
(1) Open the door.
(2) Place one cup of water in the center of the turntable tray in the oven cavity.
(3) Touch the " STEAKS/CHOPS " pad once.
(4) Close the door.
(5) Touch the " START " button.
(6) The oven is in Defrost center cooking condition.
(7) The oven will operate as follows.
Menu 1ST STAGE 2ND STAGE
Steaks/Chops LEVEL TIME LEVEL TIME
0.5lbs 60% 57sec. 40% 17sec.
(8) If improper operation is indicated, the control unit is probably defective and should be checked.
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.
P FOIL PATTERN ON THE PRINTED WIRING BOARD TEST