23
7. Temperature
The temperature readout must be calibrated or manually set before attempting Specific Ion or pH
calibration. The decimal point is replaced by a “
∗∗
” if the reading is not calibrated.
7.1 Temperature Calibration
1.
Plug the temperature sensor into the
Temp.
socket.
2.
Switch the meter on.
3.
Place the temperature sensor into a beaker of room temperature water, alongside a good quality
mercury thermometer. Stir the probe and the thermometer gently to ensure an even temperature
throughout the beaker.
4.
Select Temperature Calibration (
→
→
F1:Calibrate
F1:Calibrate
→
→
F4:Temperature
F4:Temperature
).
The Temperature Calibration screen is now displayed. For example…
Enter Actual Temperature : _ 24.0
Enter Actual Temperature : _ 24.0
O
O
C
C
Temperature Calibration Menu Quits
Temperature Calibration Menu Quits
The current reading from the Temperature sensor is displayed on the far right of the top line.
5.
When this reading has stabilised, use the Numeric Keypad to enter the same temperature as
measured by the mercury thermometer.
6.
Press the
key to calibrate the temperature readout.
Alternatively, press the
key to abort temperature calibration.
7.2 Temperature Calibration Notes
1.
Temperature calibration information is retained in memory when the
900-I3
is switched off,
even when the power supply is removed. This information can be recalled later using the GLP
function (see section 8).
2.
Temperature does not need to be re-calibrated unless the Temperature sensor is replaced or the
meter is initialised.
7.3 Calibration Messages
1.
If a temperature calibration has been successfully performed, the
900-I3
will display the
following message and the offset of the sensor.
Temperature Calibration OK
Temperature Calibration OK
0.1
0.1
O
O
C Offset
C Offset
2.
If a temperature calibration has failed, the
900-I3
will display the following message, and the
failed offset value of the sensor.
Temperature Calibration Failed
Temperature Calibration Failed
11.0
11.0
O
O
C Offset
C Offset
3.
The
900-I3
has an allowable Offset range of -10.0 to +10.0
O
C
. If calibration fails due to the
Offset being outside these limits, then please consult the Troubleshooting guide (section 16.3)
for possible remedies.