Teledyne LXT-230 manual 6.9Temperature Calibration - Trim Adjustment, Procedure for trim adjust

Procedure:

1.Press the appropriate MENU SELECTION key to reach the Output Calibration Menu.

2.Position the cursor on the top line to change the 4 mA point or the bottom line to change the 20 mA point.

3.Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode.

4.To change the value, position the cursor under the desired digit using the left-hand CALIBRATE key.

5.Increase or decrease the value by pressing the appropriate vertical CALIBRATE key.

6.When the desired value is reached, file the calibration and exit the calibrate mode by pressing either MENU SELECTION key.

6.9Temperature Calibration - Trim Adjustment

When the process demands a tighter tolerance than ±3ºC the LXT-230 allows adjustment, or trim, of the temperature compensation element. This adjustment only compensates for deviations in the RTD input (as a sensor input standardize or zero adjustment).

Procedure for trim adjust:

1.Begin with the temperature sensing element (located in the sensor) in a solution of known temperature. If the temperature is not known, insert a precision thermometer in the same solution and allow it time to stabilize.

2.Press the appropriate MENU SELECTION key to reach the Temperature Calibration Menu.

3.Position the cursor on the top line.

4.Press both horizontal CALIBRATE keys simultaneously to enter the calibrate mode. Observe the cursor move under the last digit.

5.Position the cursor under the desired digit using the left-hand CALIBRATE key.

6.Dial in the difference between the displayed temperature and the actual temperature.

NOTE

Make temperature adjustments slowly to allow time for the bottom line of the display to update. This can take 5 to 7 seconds.

7.When the desired temperature value is reached, file the calibration and exit the calibrate mode by pressing either MENU SELECTION key. The value on the top line expresses the temperature error or deviation between the RTD and the precision thermometer. The value on the bottom line expresses the real-time process temperature.

6.10Temperature Units Calibration - Celsius/Fahrenheit Conversion

The Temperature Calibration Menu is also used to change the units of display to either Celsius or Fahrenheit. The change is performed as a toggle function and changes the displayed units to the desired unit of measurement on all screens or menus where temperature is displayed.

The following procedure describes how to use this feature.

Procedure:

1.Press the appropriate MENU SELECTION key to reach the Temperature Calibration Menu.

2.Position the cursor on the bottom line under the "U" in Unit.

3.Press both horizontal CALIBRATE keys simultaneously. Observe the unit of measurement change.

Model LXT-230 Instruction Manual / 16