GE Moisture Image 1 Series Service Manual page 91

A. Instructions for Karl
Fischer Analysis
Application of the Hygrometer (900-901D1)
To perform a Karl Fisher analysis, use the apparatus in Figure A-3 on
page A-33 and complete the following steps:
1. Fill the glass bottle completely with the sample liquid.
2. Close both valves and turn on the magnetic stirrer.
3. Permit sufficient time for the entire test apparatus and the sample
liquid to reach equilibrium with the ambient temperature.
4. Turn on the hygrometer and monitor the dew point reading. When
a stable dew point reading indicates that equilibrium has been
reached, record the reading.
5. Insert a syringe through the rubber septum and withdraw a fluid
sample for Karl Fischer analysis. Record the actual moisture
content of the sample.
6. Open the exhaust valve.
7. Open the inlet valve and increase the moisture content of the
sample by bubbling wet N
moisture content by bubbling dry N
8. When the hygrometer reading indicates the approximate moisture
content expected, close both valves.
9. Repeat steps 3-8 until samples with several different moisture
contents have been analyzed.
through the liquid (or decrease the
2
through the liquid).
2
June 2003
A-29