Lincoln 1100 Series service manual Sequence Of Operations

SEQUENCE OF OPERATIONS - 1151

MODEL 1151	ELECTRIC 200 VAC	60 HZ	3 PHASE
POWER SUPPLY	Electrical power to be supplied to the oven by a four conductor service.
CONTROL BOX AUTO	When the temperature in the control box reaches
COOL DOWN	120°F ± 3°F (48.9°C ± 1.7°C), the Cooling Fan
	Thermostat closes, switching power to the Cooling Fans. The thermostat
	will open at 100°F ± 3°F(37.8°C ± 1.7°C) interrupting power to Cooling
	Fans.
MAIN FAN CIRCUIT	Power is permanently supplied through a 1A fuse to the primary of the
	step-down transformer. The transformer steps the voltage down to 120
	VAC for the control circuit. 120 VAC is supplied to terminal #1 of the 20
	minute time delay relay, through the normally closed hi-limit thermostat, to
	a normally open contact of the oven start relay, the cooling fan thermostat
	and to the normally open main fan switch.
	Closing the fan switch energizes the oven start relay. These normally open
	contacts now close enabling the 20 minute timer delay. The 20 minute
	time delay relay supplies 120 VAC to the coil of the oven fan relay, these
	normally open contacts now close supplying 200 VAC to the main fan
	motor. The cooling fans, time/temp display, conveyor switch and heat
	switch are also energized.
HEATER CIRCUIT	Closing the Heater Switch supplies 120 VAC through the normally open
	Air Pressure Switch (which was closed by Main Fan Air Pressure), through
	the 3 Amp Fuse, to the Temperature Control Board and to the Heater
	Lamp.
TEMPERATURE CONTROL	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.
CONVEYOR DRIVE	Closing the Conveyor Switch supplies 120 VAC to the DC Motor Control
	Board at terminals L1 and L2. AC volts are converted to DC volts and are
	supplied to the Conveyor Motor at terminals A+ and A-. Adjustment
S/N 2011383 and above	of the Speed Control Potentiometer (5,000 ohm, 10 turn)
REFER TO PAGE B15	will change resistance at terminals P1, P2, and P3
	varying the DC voltage to the Conveyor Motor. Thespeed of the conveyor
	motor will increase or decrease as the DC voltage from the board in-
	creases or decreases respectively. As the motor turns, it drives both the
	reducergear box and the Tach. Generator. The tach. generatoris a DC
	voltage generator which supplies a voltage to the DC Motor Control Board
	and is used as a reference formaintaining a constant conveyor speed.
TIME/TEMP DISPLAY	The secondary output of the Display Transformer, is supplied to terminals
	1, 2, and 3 of the Time/Temp. Display. The secondary output of Trans-
	former is nominally 12.5 to 15 VAC with a center tap. The voltage from
	center tap to each leg is 1/2 the secondary voltage.

Impinger II - 1100 Series Service Manual - International 7