Vulcan-Hart Solid State Temperature Control Calibration SG4D/SG6D, Calibration Steps

b.If incorrect, check temperature probe as outlined under Temperature Probe Test (SG4D/SG6D).

1)If temperature probe is functioning properly and the temperature controller failed the test in 8c above, replace the temperature control and check for calibration as outlined under Solid State Temperature Controller Calibration (SG4D/SG6D).

SOLID STATE TEMPERATURE

CONTROL CALIBRATION

(SG4D/SG6D)

Before attempting any calibration, see Section 8C of

SOLID STATE TEMPERATURE CONTROLLER TEST (SG4D/SG6D) on previous page.

Calibration Steps

1.Place a thermocouple in the geometric center of the oven cavity.

2.Set the ON/OFF/OVEN COOL switch to ON.

3.Set the temperature controller dial to 350°F. Set the power control to 100% (10).

4.Allow the oven temperature to stabilize (minimum three heating cycles).

5.Record the temperature at which the Heat lamp comes ON (heating starts) and goes OFF (heating stops). This is the control differential. Heat lamp OFF temp - Heat lamp ON temp = Control Differential.

6.The nominal control differential should be less than 20°F.

A.If the control differential is less than 20°F, the temperature control circuit is functioning properly. Proceed to step 7.

B.If the control differential is more than 20°F, check the temperature probe as outlined under Temperature Probe Test (SG4D/SG6D).

C.If the control differential is more than 20°F and the probe passes its' test parameters, then temperature controller is malfunctioning. Install a new temperature controller and run calibration steps again.

7.Calculate the average oven temperature by adding the actual minimum temperature to the actual maximum temperature and dividing by 2.

EXAMPLE:

Oven set to 350°F.

Actual minimum oven temperature = 335°F Control cuts on at 334°F

Actual maximum oven temperature = 347°F Control cuts off at 340°F

335 + 347 = 682

682/ 2 = 341 (the control is 9°F out of calibration) 340 - 334 = 6°F Control Differential

347 - 335 = 12°F Oven Temperature Differential

A.If the average oven temperature is within +/- 5°F from the dial setting, no calibration is necessary.

B.If the average oven temperature is not within +/- 5°F, calibration is recommended.

8.Loosen the set screw on the temperature controller and carefully remove the knob from the shaft, without rotating the shaft. This will expose the calibration adjustment control access hole in the front panel.

9.Monitor the internal oven temperature and determine at what temperature the control should cut on to give you the required minimum temperature (Example: 350-341=9; 334+9=341. 341°F is the temperature at which you would wish the controller to cut on).

10.After allowing the oven to operate through several cycles (minimum 3 cycles), monitor the temperature as it falls to the desired "cuts on" point. Using a small screw driver, adjust the calibration adjustment until the controller cuts on at the desired "cuts on" temperature.

11.The calibration control is adjusted clockwise in order to increase the set temperature and counter clockwise to decrease the set temperature.

12.The controller has only +/- 25°F of adjustment. 1/4 turn of the calibration adjustment represents approximately 20°F shift in calibration.

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