MODEL SOLU COMP II | SECTION 6.0 |
| CALIBRATION |
6.2.2 Procedure
1.Remove the sensor from the process. Place it in an insulated container of water along with a calibrated ther- mometer. Submerge at least the bottom two inches of the sensor. Stir continuously.
2.Allow the sensor to reach thermal equilibrium. For some sensors, the time constant for a change in tempera- ture is 5 min., so it may take as long as 30 min. for temperature equilibration.
3.If the sensor cannot be removed from the process, measure the temperature of a flowing sample taken from a point as close to the sensor as possible. Let the sample continuously overflow an insulated container hold- ing a calibrated thermometer.
4.Change the Solu Comp II display to match the calibrated thermometer using the procedure below.
Calibrate | Hold |
Program | Display |
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Calibrate? |
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Sensor1 | Sensor2 |
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CalSensor1? |
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Measurement | Temp |
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Live | 25.0°C |
CalS1 | +25.0°C |
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ManualTemp?
S1: +25.0°C
CalSensor1?
Measurement Temp
Calibrate?
Sensor1Sensor2
a.Press MENU. The main menu screen appears. Choose Calibrate.
b.Choose Sensor1 (pH) or Sensor2 (conductivity).
c.Choose Temp.
d.If the analyzer was programmed in Section 5.6 to use the actual process temperature, the screen at left will appear. To calibrate the temperature, change the number in the second line to match the temperature meas- ured with the standard thermometer. Press ENTER. Go to step f.
If the calibration temperature is more than 2 or 3°C different from the live reading, see Section 8.3.1 or Section 8.4.2.
If the analyzer was programmed to use a temperature entered by the user, go to step e.
e.The screen at left will appear if the analyzer was programmed for manu- al temperature compensation. Change the temperature to the desired value, then press ENTER. The analyzer will use the temperature entered in this step in all measurements and calculations, no matter what the true temperature is.
f.The screen at left will appear. Press EXIT.
g.Choose the other sensor and calibrate its temperature response.
h. To return to the main display, press MENU followed by EXIT.
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