Read Sharp R-98STMA (serv.man6) Service Manual online
panel. When the open button is pushed, the open lever is pushes
lower latch head on the door upward. The upper latch head is linked
with the lower latch head, so now, the door can be opened.
latch head on the door while the door is closed. The switch is intended
to render the oven inoperative by means of blowing the fuse F8A when
the contacts of the monitored latch switch fail to open when the door is
closed and contacts (COM-NO) open. At this time the contacts
(COM-NO) of monitored latch switch is in the OFF condition (con-
tacts open) due to their being normally open contact switches.
contacts (COM-NO) of monitored latch switch and stop switch are
closed. (On opening the door, each of these switches operate
ing of the monitor switch (COMNC) contacts.
MONITOR SWITCH FOR PROPER OPERATION. (REFER
TO CHAPTER “TEST PROCEDURE”).
fuse 20A blows to prevent an electric shock of fire hazard.
tact (COM-NC) closes.
of high voltage transformer is shorted.
temperature goes up higher than 125
will open and switch off all the electrical parts. The defective thermal
cut-out must be replaced with a new one.
cooking, convection cooking or dual cooking. If the temperature rises
opens and switches off all the electrical parts. When the cut-out cools
itself down to the operating temperature of 155
ing. If the temperature of the thermal cut-out rises above 170
obstructed or the other abnormal matter occurs, the thermal cut-out
opens and switches off the convection heating element and the other
electrical parts. When the cut-out cools itself down to the operating
temperature of 155
in both directions. And it prevents the temperature rise of the high volt-
age transformer by blowing the fuse F8A when the high voltage recti-
fier is shorted.
fier or high voltage rectifier are shorted when the each peak reverse
voltage goes beyond the each rated peak reverse voltage. (The pro-
cess of the blowing the fuse F8A.)
might flow back in the power circuit.
air is directed through the air vanes surrounding the magnetron and
cools the magnetron. This air is channelled through the oven cavity to
remove steam and vapours given off from heating food. It is then
exhausted through the exhausting air vents of the oven cavity.
located on the top of the oven cavity.
It is intended to heat air driven by the convection fan. The heated air is
kept in the oven and force-circulated and reheated by the convection
heated by forced circulation of the hot air produced by the grill heaters.
The air heated by the grill heating elements is circulated through the
convection passage provided on the outer casing of the oven cavity by
means of the convection fan which is driven by the convection motor. It
is then enters the inside of the oven through the vent holes provided
on the back side of the oven.
cavity through the vent in the oven cavity rear wall. In this way, the hot
air circulates inside the oven cavity to raise its temperature and, at the
same time, comes into contact with the food being cooked. When the
temperature inside the oven cavity reaches the selected temperature,
the heating elements are de-energized. When the temperature inside
the oven cavity drops below the selected temperature, the heating ele-
ments are energized again. In this way, the inside of the oven cavity is
maintained at approximately the selected temperature. When the con-
vection time reaches “0”, the heating elements are deenergized and
the convection fan stops operating and the oven shuts off. At that time
if the cavity air temperature has risen above 120
temperature (less than 105
in microwave cooking condition. LSI measures the voltage across the
temperature measurement circuit intermittently within 32-seconds time
base since the oven is started in microwave cooking condition. The
oven will stop its operation when the difference of the voltage is more
than 0.39 volts in microwave cooking condition.
ment circuit is measured.
oven cavity and stop the oven.
convection, grill or dual cooking mode, the oven is turned off.
because this condition is same as above.
and motor cam. These components are operated by a signal that
judges if microwave cooking or convection cooking operation is
selected by the CPU unit.
channelled through the cavity to remove steam and vapours given off
from the heating foods. It is then exhausted at the top of the oven cav-
ity into a condensation compartment.
leak out the oven cavity.
the open position.
unit will stop oven operation after 1 minute.
backed up has stopped