Vulcan-Hart service manual Temperature Probe Test SG4D/SG6D, Temp F Ohms

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TEMPERATURE PROBE TEST (SG4D/SG6D)

Disconnect the electrical power to the machine and follow lockout / tagout procedures.

The temperature probe used in conjunction with the Solid State Temperature controller is an RTD (resistance temperature detector) of the Thermistor type. As temperature increases the resistance value decreases.

Test Steps

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

2.Place a shielded thermocouple in the geometric center of the oven cavity and determine the temperature in the oven cavity.

3.Remove the probe lead wires from the solid state temperature controller.

4.Test the probe with an ohmmeter.

A.If the measured resistance values are inside the given tolerance, then the probe is functioning properly.

B.If the measured resistance values are outside the given tolerance, then replace the probe and make sure wires are secured to the terminals of the temperature controller. Recheck the temperature by preforming step 2.

1)Check the oven for proper operation.

5.Reverse Procedure to install.

TEMP (°F)	OHMS*

77	90,000

240	4,077

260	3,016

280	2,266

300	1,726

320	1,332

340	1,041

360	822

380	656

400	529

425	424

450	334

475	266

(*) Resistance in ohms ± 10%

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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 LocationBottom Front Cover Covers and PanelsTop 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 Catch Roller Assembly Independent Doors Roller Latch Assembly Independent DoorsDoor Window Door Switch High Limit Thermostat Lamp AssemblyInterior Lights Fan Installation Tips Cooling FANSolid State Temperature Controller Test SG4D/SG6D Service Procedures and AdjustmentsTest Steps Solid State Temperature Control Calibration SG4D/SG6D Calibration StepsTemperature Probe Test SG4D/SG6D Temp F OhmsComputer Controller SG4C/SG6C Operation Setup ModeProbe Test 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/SG6DFront View Control Panel Component PanelPlug, Socket and Components SG4C/SG6C Sequence of Operations SG4D/SG6D with Solid State Temperature ControllerCook Cycle 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