Vulcan-Hart SG4D service manual Service Procedures and Adjustments, Test Steps

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SERVICE PROCEDURES AND ADJUSTMENTS

Certain procedures in this section require electrical test or measurements while power is applied to the machine. Exercise extreme caution at all times. If test points are not easily accessible, discern power, attach test equipment and reapply power to test.

SOLID STATE TEMPERATURE

CONTROLLER TEST

(SG4D/SG6D)

Test Steps

1.Remove the right side panel as outlined under Cover and Panels in Removal and Replacement of Parts.

2.Place a thermocouple in the geometric center of the oven cavity. Oven temperature must be below 450°F.

3.Set the temperature control to the maximum setting.

4.Set the power control to 100%.

5.Check machine data plate for correct voltage to oven. Refer to diagram below for proper terminal locations and voltages before checking temperature controller. Use the correct terminals for the corresponding voltage.

6.Turn the ON-OFF-OVEN-COOL switch to ON.

7.Check for voltage across terminals J2 and J4 (120 Volt) or J2 and J9 (208/240 Volt) for power to the control.

a.If correct, proceed to step 8.

b.If incorrect, the problem is not in the temperature control (see Troubleshooting).

8.Check for voltage to the switching output.

a.For 120 VAC controls, check across terminals J3 and J4 for input voltage and between J4 and J5 for output voltage from the internal switching device.

b.For 208/240 VAC controls, check across terminals J3 and J9 for input voltage and between J9 and J5 for output voltage from the internal switching device.

1)If input voltage is correct, proceed to step 9. If input voltage is not present, the problem is not in the controller (See Troubleshooting).

2)If output voltage is correct, proceed to step 9. If output voltage is not correct, check temperature probe, as outlined under Temperature Probe Test (SG4D/SG6D).

c.If the probe connected to J6 and J7 is either shorted or opened, the red LED located just above J6 (to the left of J6 when mounted) will flash. With the probe connected and the LED not flashing, slowly turn the Temperature set knob until the pointer passes through the mid point of rotation. At the mid point of rotation, the red LED will come on. If the control is set and left at the mid point, the LED will stay on. With the LED on at mid point, you have tested the entire front end of the control circuit as well as the probe and verified that the control is functioning normally.

9.Set temperature control to minimum setting. Oven temperature must be above 300°F.

10.Check for zero volts (0.00 Volts) across terminals J4 and J5 (120 Volt) or J9 and J5 (208/240 Volt) for no output from the internal switching device.

a.If correct, temperature control is functioning properly.

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Contents SG4 & SG6 Series Full Size GAS Convection Ovens VULCAN-HART Table of Contents Table of Contents General Removal and Replacement of Parts Component LocationCovers and Panels Top Front CoverBottom Front Cover Right Side PanelControl Panel Components SG4D/SG6D SG4C/SG6CComponent Panel Components Temperature Probe SG4C/SG6C Temperature Probe ShownGAS Burners GAS Orifice GAS Solenoid ValveIgnition Control Module Spark Igniter and Flame SenseBlower and Motor Oven Doors and Bearings Door Window Roller Latch Assembly Independent DoorsDoor Catch Roller Assembly Independent Doors Door Switch Interior Lights Lamp AssemblyHigh Limit Thermostat Fan Installation Tips Cooling FANTest Steps Service Procedures and AdjustmentsSolid State Temperature Controller Test SG4D/SG6D Solid State Temperature Control Calibration SG4D/SG6D Calibration StepsTemperature Probe Test SG4D/SG6D Temp F OhmsProbe Test Operation Setup ModeComputer Controller SG4C/SG6C Computer Control Calibration SG4C/SG6C Solid State Relay TestGAS Pressure Adjustment Door Switch Adjustment Verification of Spark AT IgnitorBlower Adjustment Flame Current MeasurementDoor Adjustment Door Strike Adjustment Independent DoorsDoor Catch Roller Adjustment Electrical Operation Component DescriptionFront View Plug, Socket and Components SG4D/SG6DPlug, Socket and Components SG4C/SG6C Control Panel Component PanelFront View Cook Cycle SG4D/SG6D with Solid State Temperature ControllerSequence of Operations Timer Cycle Cool Down Cycle Solid State Temperature ControllerSG4C/SG6C with Computer Controller Normal Cook CyclePage Temperature and Time Cycle Normal Cooking Roast and Hold CycleWiring Diagrams 426574 Rev. C Schematics ThermostatGAS Convection Oven SG4 with Watlow 734 Control Troubleshooting Symptoms Possible CausesComputer Control Models only Symptom Possible Causes Symptoms Possible CausesError Codes Probable Cause Solution Problem
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