19
①
Dismantle the test cell (See sketch of test cell).
②
Clean all parts with chemical pure oil petroleum ether and benzene thoroughly.
③ C
lean the test cell again with acetone, and then rinse it clean with neutral detergent.
④
Boil 5 minutes with 5% sodium phosphate solution of distilled water, and then use
distilled water to wash a few times.
⑤
Clean all the parts with distilled water several times.
⑥
Place all the parts in an oven at a temperature between 105 and 110 deg, Dry them for
60 to 90 minutes.
⑦
Assemble them when the temperature falls below normal temperature after cleaning
all the parts.
Method 3
：
Ultrasonic cleaning methods
①
Dismantle the test cell.
②
Wash all parts with solvents.
③
Shake all parts for 20 minutes in an ultrasonic cleaner with soapy water. Take out the
parts, clean them with tap water and distilled water, and shake for 20 minutes in
distilled water.
Method 4
：
Solvent cleaning method
①
Dismantle the test cell.
②
Wash all parts with solvents, and change the solvents.
③
Wash all parts with the acetone first and then tap water. Then clean them with
distilled water.
④
Dry the parts 60
～
90 minutes in the oven at temperature of 105
～
110
℃
.
When testing a group of similar liquid samples but not used, we can use the same test cell
which doesn't need intermediate washing, as long as the last test sample has better
performance than the specified value of the measuring,. If the performance of the tested
sample is inferior to the measuring sample, the test cell must be cleaned before you make the
next test.
Ⅸ
.COMMON PROBLEMS
1. The screen displays “Please calibrating dry cell”.
A
：
The dry cell calibration is needed when the capacitance value of test cell is not in the
range of 60±5pF.
