Sharp R-3H57 Service Manual page 18

R-3H57
PROCEDURE
LETTER
N NOISE FILTER TEST
CARRY OUT 3D CHECKS.
Disconnect the leads from the terminals of the noise
filter. Using an ohmmeter, check between the terminals
as described in the following table.
If incorrect readings are obtained, replace the noise filter unit.
CARRY OUT 4R CHECKS.
O AH SENSOR TEST
Checking the initial sensor cooking condition
(1) The oven should be plugged in at least five minutes before sensor cooking.
(2) Room temperature should not exceed 35˚C.
(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 refrigerator 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 vapour given of by the spray and turn off before food is properly cooked.
(8) If the sensor has not detected the vapour 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 should be installed and screws tightened.
(1) Fill approximately 200 milliliters (7.2 oz) of tap water in a 1000 milliliter measuring cup.
(2) Place the container on the center of tray in the oven cavity.
(3) Close the door.
(4) Touch Reheat Beverage pad of SENSOR INSTANT ACTION once. Now, the oven is in the sensor
cooking condition and "REHEAT", "BEVE", "RAGE" and "SENSOR" will appear in the display.
(5) The oven will operate for the first 16 seconds, without generating microwave energy.
NOTE: ERROR will appear if the door is opend or STOP/CLEAR pad is touched during first stage of
(6) After approximately 16 seconds, microwave energy is produced, oven should turn off after water is
boiling (bubling).
If the oven does not turn off, replace the AH sensor or check the control unit, refer to explanation below.
To determine if the sensor is defective, the simplest method is to replace it with a new replacement
sensor.
TEST PROCEDURES (CONT'D)
MEASURING POINT
Between N and L
Between terminal N and WHITE
Between terminal L and RED
sensor cooking.
TESTING METHOD FOR AH SENSOR AND/OR CONTROL UNIT
COMPONENT TEST
N
L
L (min)
1.0 mH
INDICATION OF OHMMETER
Open circuit
Short circuit
Short circuit
16
WHT
L
L
RED
C
C Y
X
Cx 20% Cy 20%
0.068 F 0.0022 F