Vulcan-Hart SG4C ML-114876, Руководство по обслуживанию

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ELECTRICAL OPERATION
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.
S o l i d S t a t e T e m p e r a t u r e C o n t r o l l e r
(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 micro-amp flame sense
current that is monitored by the ignition control module.
A flame sense current of 1 micro amp (minimum and
stable) is required to maintain burner ignition.
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.
COMPONENT DESCRIPTION
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 J-type thermocouple. As the temperature
increases, a DC voltage is generated within this
thermocouple and compared to a list of temperature
values stored within the cooking computer memory to
control and maintain temperature.
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 OFF and 100%. Power level must be on
for oven to work.