Lincoln Impinger Conveyor Ovens 1633-000-EA - Manual (Page 2)

Low Profile –1600 Series Advantage Digital Service Manual – Int’l 2
SEQUENCE OF OPERATIONS
SERIAL NUMBERS L28563 AND ABOVE
(WITH PUSH BUTTON CONTROL)
MODEL 1633-000-EA 230 VAC 50HZ NATURAL GAS
MODEL 1634-000-EA 230 VAC 50HZ LP GAS
POWER SUPPLY Electrical power to be supplied to the oven by a three conductor service.
Brown conductor is hot
Blue conductor is neutral.
Green conductor is ground.
CONTROL BOX
AUTO COOL DOWN When the temperature in either one of the control boxes reaches 120
°F ±3° (49°C ±
1.7
°), the cooling fan thermostats will switch power to the cooling fans. The thermostats
will interrupt power to the cooling fans when the temperature falls to 100
°F ± 3° (37°C ±
1.7
°)
MAIN FAN CIRCUIT Line voltage is permanently supplied to a normally open contact of the oven power switch.
Line voltage is permanently supplied to the two normally open cooling fan thermostats, a
normally open contact of the oven power relay. Closing the oven power switch supplies line
voltage, through both normally closed control box hi-limit thermostats, to the oven power
relay. Its contacts now close supplying line voltage to the two main fan motors and the two
burner circuits. Closing the oven power switch also supplies line voltage to the control box
cooling fans, the control transformer, and the conveyor motor.
BURNER CIRCUIT NOTE: This oven utilizes two complete burner systems. The sequence of operations is the
same for each system.
Closing the main fan switch supplies line voltage, through the oven power relay, through a
three Amp.fuse, through the gas pressure switch (gas pressure switch removed at
S/N L31479), through the main fan air pressure switch, through the oven cavity hi-limit
thermostat, to the ignition control. The combustion motor is energized. The normally open
combustion air switch closes upon sensing air pressure. After a pre-purge period of
between 30 and 60 seconds, the ignition transformer and the main gas valve are
energized. Ignition should now occur.
TEMPERATURE
CONTROL Closing the oven power switch supplies line voltage, through the 10 amp. fuse, through the
oven power relay, to the primary of the control transformer. 24VAC is supplied to the oven
control. The oven control is set to desired temperature. The thermocouple will provide
varying millivolts to the oven control. The oven control supplies line voltage to the
temperature regulation valve at intermittent intervals to maintain desired temperature. The
display on the oven control will indicate when the temperature regulation valve is
energized.
NOTE: The display also indicates oven temperature.
CONVEYOR DRIVE Closing the oven power switch supplies line voltage, through the 10 Amp fuse, through the
oven power relay to the conveyor motor and to the primary of the control transformer.
Secondary voltage, 24VAC, is supplied to the oven control. Setting the oven control to the
desired time outputs voltage, through a reversing switch, to the conveyor motor
NOTE: The conveyor system uses a magnet and hall effect sensor to prove operation of
the conveyor motor. If the conveyor motor is not running, “BELT JAM” is indicated on the
display.