Lincoln Impinger II - Advantage Series - Manual (Page 3)

Impinger II –Advantage Service Manual - Domestic 3
SEQUENCE OF OPERATIONS
IMPINGER II ADVANTAGE
MODEL 1116-000-A / NATURAL GAS / 120 VAC / 60 HZ / 1 PHASE
MODEL 1117-000-A / L.P. GAS / 120 VAC / 60 HZ / 1 PHASE
POWER SUPPLY Electrical power is supplied to the oven by a three conductor cordset. Voltage
from the black conductor to the white conductor is 120 VAC. The white
conductor is neutral. The green conductor is ground.
CONTROL BOX AUTO
When the temperature in the control box reaches 120°F ± 3° (48.9°C ± 1.7°C),
the
COOL DOWN interrupt power to the fans when the control box temperature falls to 100°F ± 3°
(37.8°C ± 1.7°C).
MAIN FAN CIRCUIT
Power is permanently supplied, through a 10A fuse, and through a normally
closed control box hi-limit thermostat, to the normally open main fan switch.
Power is also supplied to the normally open cooling fan thermostat. Closing the
main fan switch supplies 120 VAC to the main fan motor, the cooling fan motor,
the primary of the temperature display transformer, the heat and conveyor
circuits.
BURNER CIRCUIT
Closing the main fan switch supplies 120 VAC to the burner blower motor. 120
VAC is also supplied, through the normally closed oven cavity hi-limit thermostat,
the main fan centrifugal switch (this switch closes when main fan reaches
approximately 1600 RPM) to the electronic temperature control and to the
primary of the burner transformer.
IGNITION CONTROL
The ignition control operates on both 24 VAC and 120 VAC. When the control is
energized by 24 VAC from the transformer, 120 VAC is switched by the ignition
control to the hot surface ignitor for 45 seconds for the hot surface ignitor warm
up. The ignitor glows red, 24 VAC is switched to the gas valve which opens and
ignition should now occur.
TEMPERATURE CONTROL
When the centrifugal switch of the main fan motor closes, power is applied to the
temperature control. The 1K ohm temperature pot is adjusted to desired
temperature. The thermocouple will provide varying millivolts to the temperature
controller. The temperature controller supplies 120 VAC to the solenoid valve at
intermittent intervals to maintain desired temperature. The heat lamp is
energized with the solenoid valve.
CONVEYOR DRIVE
Closing the on/off switch supplies 120 VAC to the motor control board. AC volts
are converted to DC volts and are supplied to the conveyor motor at terminals A+
and A-.
Adjustment of the speed control potentiometer will change resistance at terminals
P1 and P2 varying the DC voltage to the motor. The speed of the conveyor
motor will increase or decrease as the DC voltage from the board increases or
decreases respectively.
NOTE:
The conveyor control uses a sensor and magnet, mounted on the conveyor
motor that senses the motor speed. Any change in motor load (±RPM) is
detected by the sensor and the voltage to the motor is adjusted accordingly.
Temperature Display
Closing the switch supplies 120 VAC to the primary of the temperature display
transformer. The secondary of this transformer supplies 12 VAC to the temperature
display. The thermocouple supplies D.C. millivolts to the temperature display. The
display converts this millivolt reading to a temperature reading.