Sharp R-870B, Руководство по обслуживанию

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R-870B
5
the top and bottom heaters.
3. When the oven temperature reaches the selected
preheat temperature, the following operations occur:
3-1. The heater relays RY3+RY4 de-energized by the
CPU unit temperature circuit and thermistor, opening
the circuit to the top and bottom heaters.
3-2. The oven will continue to function for 30 minutes,
turning the top and bottom heaters on and off, as
needed to maintain the selected preheat tempera-
ture. The oven will shut-down completely after 30
minutes.
CONVECTION COOKING CONDITION
When the preheat temperature is reached, a beep signal
will sound indicating that the holding temperature has
been reached in the oven cavity. Open the door and place
the food to be cooked in the oven. Select the cooking
temperature by pressing the CONVEC pad. And then
enter the cooking time by pressing the NUMBER pads.
When the START pad is touched, the following operations
occur:
1. The numbers of the digital read-out start the count
down to zero.
2. The oven lamp, turntable motor, cooling fan motor and
convection motor are energized.
3. The relays(RY3 and RY4) are energized (if the cavity
temperature is lower than the selected temperature)
and the main supply voltage is applied to the heating
element to return to the selected cooking temperature.
The top heaters and the bottom heater work in accord-
ance with the following table while the heaters are
energized.
Selected Temp- Top Heaters Bottom Heater
erature (˚C) Power (%) Power (%)
250 40 40
230 40 40
220 40 40
200 30 70
180 20 70
160 10 70
150 10 70
130 10 60
70 10 40
40 10 30
4. Upon completion of the cooking time, the audible
signal will sound, and oven lamp, turntable motor,
cooling fan motor and convection motor are de-ener-
gized. At the end of the convection cycle, if the cavity
air temperature is above 120˚C, the circuit to (RY5) will
be maintained (by the thermistor circuit) to continue
operation of the cooling fan motor until the temperature
drops below 104˚C, at which time the relay will be de-
energized, turning off the fan motor. Relay (RY1) will
however, open as soon as the convection cycle has
ended, turning off the convection fan motor.
GRILL COOKING CONDITIONS
The oven has three grill cooking condition. They are the
TOP HEATER mode, BOTTOM HEATER mode and
DOUBLE GRILL mode.
TOP
HEATER
MODE
In this mode, the food is cooked by the top heaters. Press
the GRILL pad once and then enter the cooking time by
pressing the number pads. When the START pad is
pressed, the following operations occur:
Figure O-4(a) on page 35
1. The relay RY3 + RY5 + RY6 are energized.
2. The numbers of the digital read-out start the count
down to zero.
3. Then the top heaters, turntable motor, oven lamp and
fan motor are energized.
4. Now, the food is grilled by the top heaters.
5. Upon completion of the selected cooking time, audible
signal sounds and the contacts of relays RY3 + RY6
are opened, then the top heaters, turntable motor and
oven lamp are de-energized. But the relay RY5 stays
closed and the fan motor operates for 5 minutes. But if
the cooking time is less than 2 minutes the relay RY5
will not stay close.
BOTTOM
HEATER
MODE
In this mode, the food is cooked by the bottom heater.
Press the GRILL pad twice and then enter the cooking time
by pressing the number pads. When the START pad is
pressed, the following operations occur:
Figure O-4(b) on page 36
1. The relay RY4 + RY5 + RY6 are energized.
2. The numbers of the digital read-out start the count
down to zero.
3. Then the bottom heater, turntable motor, oven lamp
and fan motor are energized.
4. Now, the food is grilled by the bottom heater.
5. Upon completion of the selected cooking time, audible
signal sounds and the contacts of relays RY4 + RY6
are opened, then the bottom heating elements, turnta-
ble motor and oven lamp are de-energized. But the
relay RY5 stays closed and the fan motor operates for
5 minutes. But if the cooking time is less than 2 minutes
the relay RY5 will not stay close.
DOUBLE GRILL MODE
In this mode, the food is cooked by both the top heaters
and bottom heater. Press the GRILL pad three times and
then enter the cooking time by pressing the number pads.
When the START pad is pressed, the following operations
occur:
Figure O-4(c) on page 36
1. The relay RY3 + RY4 + RY5 + RY6 are energized.
2. The numbers of the digital read-out start the count
down to zero.
3. Then the top heaters, bottom heater, turntable motor,
oven lamp and fan motor are energized.
4. Now, the food is grilled by the top heaters and the
bottom heater.
5. Upon completion of the selected cooking time, audible
signal sounds and the contacts of relays RY3 + RY4 +
RY6 are opened, then the top heating elements, bottom
heating element, turntable motor and oven lamp are de-
energized. But the relay RY5 stays closed and the fan
motor operates for 5 minutes. But if the cooking time is
less than 2 minutes the relay RY5 will not stay closed.
MIX COOKING CONDITION
The oven will cook food by supplying top heaters and/or
bottom heater and microwave energy alternately within a
48 seconds time base. And the oven has four programmed
cooking mode.