Lincoln Impinger Conveyor Ovens 1633-000-EA, Service Manual

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Low Profile – 1600 Advantage Series Service Manual – International 3
SEQUENCE OF OPERATIONS
MODEL 1633-000-EA 230 VAC 50HZ NATURAL GAS
MODEL 1634-000-EA 230 VAC 50HZ L.P. 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 to 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 temp. display, and the conveyor circuit.
BURNER CIRCUIT
NOTE: This oven utilizes two complete burner/ temperature control 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, 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 oven power relay, through a three amp. fuse,
through the gas pressure switch, through the main fan air pressure switch through the oven cavity hi-limit
thermostat, to the temperature control board. The 1.0K temperature pot. is adjusted to desired temperature. The
thermocouple will provide varying millivolts to the temperature control. The temperature control supplies line
voltage to the solenoid valve at intermittent intervals to maintain desired temperature.
CONVEYOR DRIVE
Closing the oven power switch supplies line voltage, through the oven power relay, through the electromagnetic
filter to the conveyor control. AC volts are converted to DC volts and are supplied to the conveyor motor at
terminals A+ and A-.