46
Stage 2
steps:
Note:
A temperature bath at 25.0 ±1 °C is required for this
measurement.
• Press
from the keypad.
• An instruction prompt will pop up with instructions for sample
preparation.
• Using measurement technique outlined in direct measurement,
place probe into sample.
• Press
.
• The meter will begin to evaluate stability of the conductivity
measurement. At the conclusion of the test period the results
will be displayed. If the sample has passed the evaluation the
testing is finished and the water may be used.
• Press
to store a copy of the sample results. This may
be printed using
HI 92000
software.
Note:
A separate pH meter and sensor is required.
Stage 3
- this is an off-line test that studies the pH and CO
2
.
If the water sample has failed Stage 1 and Stage 2 tests, Stage 3
testing must be conducted.
To perform this test pH measurement is required. Have a
calibrated pH sensor.
Stage 2
- this is an off-line test.
To perform this test:
• Store the water sample in an enclosed clean container that
has been rinsed previously with water of the same quality.
• Adjust the sample’s temperature to 25 °C and agitate the
sample to ensure that it has equilibrated with ambient CO
2
.
• If the measured conductivity is less than 2.1 µS/cm, then the
sample has met the USP requirements.
• Otherwise, proceed to Stage 3 testing.