ELECTRICAL OPERATION
COMPONENT DESCRIPTION
Master Switch (S1) - Determines the mode of operation; ON, OFF or OVEN COOL
Lights Switch (S2) - Controls the oven cavity lights.
Fan Speed Switch Hi/Low (S3) - Controls blower motor speed between HI and LOW settings. Available on models SG4D/SG6D.
Alarm/Buzzer - Signals the end of the normal cook cycle when cooking time expires.
Timer - Times the cooking cycle and signals the buzzer at the end of the cycle.
Door Switch - Allows the oven to operate when the doors are closed but stops the oven from operating when the doors are opened.
Blower Motor - Operates the oven cavity blower. Also, an internal centrifugal switch on the motor is utilized to allow the connection of power to the heat relay when the motor is at operating speed.
Transformer (T1) - Provides 24 VAC power to the ignition control module and heating circuit.
Motor Control Relay(s) (SG4C/SG6C) - Provides power to HI and LOW speed motor windings based on operator requirements.
Solid State Temperature Controller (SG4D/SG6D) - Monitors temperature sensor and regulates the oven cavity temperature by controlling the heat relay through the blower motor centrifugal switch contacts.
Ignition Control Module - Provide ignition spark and monitors burner(s) flame current during ignition sequence.
Ignition Electrode and Flame Sense Device - Ignites the gas and senses the presence of a flame. The flame presence generates a
Power On Light (SG4D/SG6D) - Lit whenever the Master Switch (S1) is turned to ON or OVEN COOL mode.
Heat Light - Lit whenever temperature controller is calling for heat.
No Ignition Light (SG4C/SG6C) - Lit when power is turned ON, during ignition trial and gas purge time and when no flame is detected by flame sensor. If the oven fails to ignite after three attempts, it will remain lit until power is reset.
Temperature Probe (SG4D/SG6D) - This temperature probe is a thermistor device. A thermistor is a calibrated resistor which changes resistance with the temperature. As the temperature increases, the resistance of the thermistor decreases. The resistance of the probe is compared to the resistance of the temperature controller resistor in to control and maintain temperature.
Temperature Probe (SG4C/SG6C) - This temperature probe is a
High Limit Thermostat - Protects the oven from temperatures above 550°F by removing power from the first valve (safety) on the dual solenoid gas valve which stops the flow of gas to the burner. Auto resets at 500°F.
Gas Valve (Dual Solenoid) - Contains two valves. The first valve is opened when the unit is turned on and the limit temperature is not exceeded. The second valve is turned by the heating system. Both valves must be open in order to get gas to the main burners.
SSR1 and SSR2 (SG4C/SG6C) - When SSR1 is energized, it connects power to the blower motor for HI fan speed operation. When SSR2 is energized, it connects power to blower motor for LOW speed operation.
Cooling Fan - Circulates cooler air from rear of oven forward to cool components in the control area.
Computer Control (SG4C/SG6C) - Monitors temperature sensor and regulates the oven cavity temperature by controlling the heat relay (R1) through the blower motor centrifugal switch contacts. Also, counts the time of the product and signals the electronic alarm at the end of the cook cycle.
Power Level Control - Selects the percent of heat input between 22% and 100%. Power level must be on for oven to work.
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