Thermo Electron 96-09, Инструкция по эксплуатации, Страница: 14 / 50

Direct Calibration
Setup
1. Remove the rubber cap covering the electrode(s) tip.
2. If using Orion 94-09 electrode with Orion 90-01 Reference
Electrode, fill the reference electrode chamber with
Orion No. 900001. If using Orion 96-09, fill the chamber
of the electrode with Orion No. 900061.
3. Connect electrode(s) to meter.
4. Prepare two standards that bracket the expected sample
range and differ in concentration by a factor of ten.
Standards can be prepared in any concentration unit to suit
the particular analysis requirement. All standards should be
at the same temperature as the samples (for details on
temperature effects on electrode performance, refer to
Temperature Effects ).
Using a meter with direct concentration readout capability
See individual meter instruction manuals for more
specific information.
1. Measure 50 mL of the more dilute standard and 50 mL of
TISAB II or 5 mL of TISAB III into a 150 mL beaker.
Stir thoroughly.
2. Rinse electrode(s) with deionized water, blot dry and place
into the beaker. Wait for a stable reading. Then calibrate the
meter to display the value of the standard as described in the
Meter Instruction Manual.
3. Measure 50 mL of the more concentrated standard and
50 mL of TISAB II or 5 mL TISAB III into a 150 mL beaker.
Stir thoroughly.
4. Rinse electrode(s) with distilled water, blot dry, and place
into the beaker with the more concentrated standard. Wait
for a stable reading then adjust the meter to display the value
of the second standard as described in the
Meter
Instruction Manual.
5. Measure 50 mL of the sample and 50 mL of TISAB II or
5 mL of TISAB III into a 150 mL beaker. Stir thoroughly.
6. Rinse electrode(s) with deionized water, blot dry and
place into sample. The concentration will be displayed
on the meter.
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