R-950A
5
the damper switch contacts. The opening of the damper
switch contacts sends a signal to the LSI on the CPU
unit de-energizing the relay (RY4) and opening the
circuit to the damper motor.
3. The coil of heater relay (RY3) is energized by the CPU
unit and the main supply voltage is added to the
convection heater.
4. When the oven temperature reaches the selected
preheat temperature, the following operations occur:
4-1. The heater relay (RY3) is de-energized by the CPU
unit temperature circuit and thermistor, opening the
circuit to the convection heater.
4-2. The oven will continue to function for 30 minutes,
turning the convection heater on and off, as needed
to maintain the selected preheat temperature. The
oven will shutdown completely after 30 minutes.
CONVECTION COOKING CONDITION (Figure O-3)
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. Press the CONVEC-
TION pad and then enter the cooking temperature by
pressing the temperature 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. Heater relay (RY3) is energized (if the cavity temperature
is lower than the selected temperature) and the main
supply voltage is applied to the convection heater to
return to the selected cooking temperature.
4. Upon completion of the cooking time, the audible
signal will sound, and oven lamp, turntable motor,
cooling fan motor, convection motor and convection
heater are de-energized. At the end of the convection
cycle, if the cavity air temperature is above 118˚C, the
circuit to (RY6) will be maintained (by the thermistor
circuit) to continue operation of the cooling fan motor
until the temperature drops below 118˚C, at which time
the relay will be de-energized, turning off the fan motor.
Relay (RY5) will however, open as soon as the
convection cycle has ended, turning off the convection
fan motor. This will now cool and allow the damper door
to open.
5. At the end of the convection cook cycle, shut-off relay
(RY4) is energized turning on the damper motor. The
damper is returned to the open position, closing the
damper switch contacts which send a signal to the
control unit, de-energizing shut-off relay (RY4).
SIMUL CONVECTION COOKING CONDITION
(Figure O-5)
Press the SIMUL CONVEC pad. And then enter 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 shut-off relays (RY1+RY5+RY6) are energized,
turning on the oven lamp, turntable motor, cooling fan
motor and convection motor.
3. The shut-off relay (RY4) is energized.
The damper door is closed from the open position.
4. The power supply voltage is added to the convection
heater and power transformer at the same time.
5. The convection heater operates through the heater
relay (RY3) contacts and the power transformer
operates through the cook relay (RY2) contacts.
6. Upon completion of the cooking time, the audible
signal will sound, and oven lamp, turntable motor,
cooling fan motor, convection motor and power
transformer are de-energized. At the end of the cooking
cycle, if the cavity air temperature is above 118˚C, the
circuit to (RY6) will be maintained (by the thermistor
circuit) to continue operation of the cooling fan motor
until the temperature drops below 118˚C, at which time
the relay will be de-energized, turning off the fan motor.
The relationship between the convection and microwave
power operations are as follows.
16 SEC.
32 SEC.
SIMUL CONVECTION
MICROWAVE POWER
= APPROX. 30%
CONVECTION
TEMPERATURE
= 230˚C
ON
OFF
ON
(MICRO.)
(CONVEC.)
NOTE:
1) The simul convection is programmed for 230˚C
with 30% microwave power. The microwave power
and convection temperature can be changed, but
the High (100%) and 250˚C can not be selected.
2) The relay (RY2) is operated by the CPU unit to
supply within a 48 second time base microwave
energy.
3) During simul convection operation, the convection
heater is energized only if the cavity temperature
drops below the set temperature.
4) The ON and OFF time ratio does not correspond
with the percentage of microwave power, because
approx. 2 seconds are needed for heating of the
magnetron filament.
5) "SIMUL" means "Simultaneous".
GRILL COOKING CONDITION (Figure O-4)
Press the GRILL pad and then enter the cooking time by
pressing the number pads. When the START pad is
touched, the following operations occur:
1. The coil of shut-off relays RY1+RY6+RY7 are
energized, the oven lamp, cooling fan motor and
turntable motor are turned on.
2. The coil of relay (RY4) is energized by the CPU unit.
The damper is moved to the closed position, opening
the damper switch contacts. The opening of the damper
switch contacts sends a signal to the LSI on the CPU
unit de-energizing the relay (RY4) and opening the
circuit to the damper motor.
3. The coil of relay (RY7) is energized by the CPU unit and
the main supply voltage is added to the grill heater.
4. At the initial period, the relays RY3 and RY5 are
energized and the convection heater and convection
motor are energized until the cavity air temperature
reaches 220˚C.
5. When the temperature exceeds 220˚C, the convection
