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Selecting Programmed Test Temperature
•
Determining the Test Temperature
Generally, use the highest temperature possible without causing other
‘undesirable’ conditions (such as melting or excessive release of other volatiles).
The instrument is relatively insensitive to the exact temperature used. Too low a
temperature will result in long test times and possibly low results.
In most cases, it is important that the sample not melt. A melted sample may
form an impermeable skin and trap moisture, producing a low result.
•
The following guidelines will help.
If you have another moisture determination method (reference method), set the
test temperature to the same temperature as used in your reference method.
If the melting temperature is known, use a temperature 10 or 20 degrees lower.
•
To program test temperatures:
Highlight
TEMPERATURES
on the
EDIT MEMORY START MENU.
Press
[Selct]
, then
[Edit]
.
Use the
[Left]
and
[Right]
keys to move the cursor’s position left and right to the
digit to be changed.
Use the
[Incr]
and
[Decr]
keys to scroll through the numbers
When complete, press
[Quit]
followed by
[Accpt].
•
When toggled on, the
COLD START ENABLE
function allows testing to begin at
an ambient temperature. During the test, the oven will ramp-up to the pre-
programmed temperature. The
COLD START ENABLE
is rarely used.
Selecting Units for the Final Result Display
•
Highlight
RESULT DISPLAY OPTION
.
•
Press
[Selct]
, then
[Edit]
.
Use the
[Incr]
and
[Decr]
keys to scroll through the options.
•
Select either:
Percentage (%) of water,
Parts per million (ppm) of water, or
Micrograms (
µ
g) of water measured.
•
Press the
[Quit]
, then the
[Accpt]
keys.
Selecting How to End the Test
•
Highlight
ENDING CRITERIA
.
•
Press
[Selct]
.
•
Use the
[Up]
and
[Down]
keys to select the type of ending value.
•
Press
[Selct]
.
RATE:
Ends the test when the moisture evolved from the sample drops below the programmed
microgram per second value. Use RATE if you want to match an existing standard or method
that utilizes RATE criteria (such as the KF titration method). This method is extremely
dependent on the amount of sample used and water collected during a test. For repeatability
testing, use a very consistent sample size within ± 0.2 gram for each test.
