Sequence Of Operations 1100 Thru 1103 - Lincoln 1100 Series Service Manual

POWER SUPPLY
MAIN FAN CIRCUIT
HEATER CIRCUIT
TEMPERATURE CONTROL
CONVEYOR DRIVE
TIME/TEMP DISPLAY
AUTOMATIC COOL DOWN
Impinger II –1100 Series Service Manual - Domestic

SEQUENCE OF OPERATIONS 1100 THRU 1103

MODEL 1100 / ELECTRIC / 120/208 VAC / 60 HZ / 1 PHASE
MODEL 1101 / ELECTRIC / 120/240 VAC / 60 HZ / 1 PHASE
MODEL 1102 / ELECTRIC / 120/208 VAC / 60 HZ / 3 PHASE
MODEL 1103 / ELECTRIC / 120/240 VAC / 60 HZ / 3 PHASE
Electrical Power to be supplied to the oven by a four conductor cord set on single
phase and a five conductor cord set on three phase.
Voltage from the black conductor to the white conductor is120 VAC.
Black conductor is Hot.
Red conductor is Hot.
Orange conductor is Hot. (Used on 3Ø only)
White conductor is dedicated neutral.
Green conductor is ground.
Power is permanently supplied to the normally open contacts of the main fan
relay, through a 10A fuse, to the normally open cool down thermostat, and to the
normally open main fan switch. Closing the main fan switch energizes the coil of
the main fan relay. Its normally open contacts now close energizing the main fan
motor. Closing the main fan switch energizes the cooling fan, the time/temp
transformer, the heat and conveyor switches.
Closing the Heater Switch provides power through the normally open Air
Pressure Switch, through the 3 Amp Fuse, to the Temperature Control Board
and to the Heater Lamp.
Closing the Heat Switch supplies 120 VAC to the Electronic Temperature
Control. The 2.5K ohm Potentiometer is adjusted to achieve the desired
temperature. The Thermocouple will provide varying millivolts to the Temperature
Control. The temperature control board then supplies 120 VAC to the coil of the
Contactor at intermittent intervals to maintain the desired temperature.
NOTE: Units with Serial Number prior to 2000782 were equipped with a Fenwall
Temperature Control and used a Temperature Control Potentiometer rated at 5K
ohms.
Closing the Conveyor Switch supplies 120 VAC to the DC Motor Control Board at
terminals L1 and L2. A.C.volts are converted to DC volts and are supplied to the
Conveyor Motor at terminals A+ and A-. Adjustment of the Speed Control
Potentiometer (5,000 ohm, 10 turn) will change resistance at terminals P1, P2,
and P3varying the DC voltage to the Conveyor Motor. The speed of the conveyor
motor will increase or decrease as the DC voltage from the board increases or
decreases respectively. As the motor turns, it drives both the reducer gear box
and the tach. generator. The tach. generator is a DC voltage generator which
supplies a voltage to the DC Motor Control Board which is used as a reference
for maintaining a constant conveyor speed.
The secondary output of the Transformer, is supplied to terminals 1, 2, and 3 of
the Time/Temp. Display. The secondary output of the Transformer is nominally
12.5 to 15 VAC with a center tap. The voltage from the center tap to each leg is
1/2 the secondary voltage. The speed side of the Time/Temp. Display uses a
slotted disc (cemented to tach. coupling) to break the infra-red light beam of the
optical encoder (mounted on gear motor), producing electrical pulses that are
transmitted to the display. The display converts these pulses into a read-out of
minutes and seconds. The temperature portion of the Time/Temp Display
thermistor outputs a resistance proportional to the oven temperature. This
resistance is then converted by the display into a temperature reading.
When the oven reaches operating temperature the normally open Oven Cool
Down Thermostat closes. After oven is switched OFF, the Thermostat bypasses
the Fan Switch , keeping the Cooling Fan and Main Fan operating until the oven
cools down to approximately 200° F (93.3° C).
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