Sharp R-1880LS Service Manual page 30

R-1880LS/LST
PROCEDURE
LETTER
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.
1. Disconnect the power supply cord, and then remove outer case.
. Open the door and block it open.
3. Discharge high voltage capacitor.
4. If the foil pattern is open, follow the troubleshooting guide given below for repair.
Problem: POWER ON, indicator does not light up.
STEPS
NOTE:* At the timeof making these repairs,
make a visual inspection of the
and examine the transformer with an ohm-
meter for the presense of a layer short-circuit
(check Primary coil resistance which is approximately 195 ohm
NOTE:*
make a visual inspection of the
V AH SENSOR TEST
Checking the initial sensor cooking condition
Warning: The oven should be fully assembled before following procedure.
(1) The oven should be plugged in at least five minutes before sensor cooking.
() Room temperature should not exceed 95
(3) The unit should not be installed in any area where heat and steam are generated. The unit should not be installed,
for example, next to a conventional surface unit. Refer to the " INSTALLATION Instructions ".
(4) Exhaust vents are provided on the back of the unit for proper cooling and air flow in the cavity. To permit
adequate ventilation, be sure to install so as not to block these vents. There should be some space for air
circulation.
(5) Be sure the exterior of the cooking container and the interior of the oven are dry. Wipe off any moisture with
a dry cloth or paper towel.
(6) The Sensor works with food at normal storage temperature.For example, chicken pieces would be at refrigera-
tor temperature and canned soup at room temperature.
(7) Avoid using aerosol sprays or cleaning solvents near the oven while using Sensor settings. The sensor will
detect the vapor given of by the spray and turn off before food is properly cooked.
(8) If the sensor has not detected the vapor of the food, ERROR will appear and the oven will shut off.
Water load cooking test
Make sure the oven has been plugged in at least five minutes before checking sensor cook operation. The cabinet
TEST PROCEDURES
OCCURRENCE
1 The rated voltage is not applied between Pin
No. 5 of the 3-Pin connector (A) and the
terminal of the relay RY1.
 The rated voltage is applied to primary side
power transformer.
3 Only pattern at "a" is broken.
4 Pattern at "a" and "b" are broken.
varistor Check for burned damage
At the timeof making these repairs,
varistor Check for burned damage
and examine the transformer with
an ohm-meter for the presense of
a layer short-circuit(check Primary
coil resistance which is approxi
mately 195 ohm ± 15%). If any
abnormal condition is detected,
replace the defective parts.
COMPONENT TEST
CAUSE OR CORRECTION
Check supply voltage and oven main unit.
Power transformer or secondary circuit defective.
Check and repair.
*Insert jumper wire (J1) and solder.
*Insert the coil RCILF003YAZZ between "c" and "d".
2
T1
b
CN - B
F(35 C).
O O
30
P
1
d
a
VRS1
CN - A
c
5 3 1
AC (N) MOTOR
CAPACITOR