Thermo 335904, Operator'S Manual, Page: 37 / 94

Note: Cells should be matched at all analytical
wavelengths because matching at one
wavelength does not guarantee matching
at others.
4. Use the arrow keys to highlight the position
where you want to enter the first wavelength.
5. Press Add nm .
6. Enter the value for the wavelength and press
ENTER .
7. Continue until you have entered all the
wavelengths.
After all the wavelengths have been entered, press
Run Corr. to start the Cell Correction program. The
Cell Correction program will measure the other
cells against the blank and will record, store and
date the measurements. From these
measurements the Cell Correction program
establishes the required correction factors, which
then are automatically applied during all
subsequent tests (if Cell Correction is activated).
Taking measurements
The spectrophotometer lets you use different cell
holders and cell holder accessories to take
measurements. When you set up your test
parameters, you will select the type of measurement
you want to use and indicate how many samples you
have. You can choose from the following options:
•
Auto 6 - You can take one blank measurement
and up to five sample measurements without
changing the samples in the cell holder. The
instrument automatically measures the blank (in
the blank position), then automatically advances
the cell holder to the appropriate position for the
next measurement. This option is available only
with the 6-Position Cell Holder.
• Auto 3 - You can take up to three
measurements without changing the samples in
the cell holder. The instrument automatically
measures the blank (in the blank position),
then automatically advances the cell holder to
the appropriate position for the next
measurement. This option is available only with
the 6-Position Cell Holder.
• Single Cell Platform - You place the blank in
the cell holder, measure it, place a sample in
the cell holder, then measure your sample.
This process is completely manual. In fact, the
cell position buttons on the keypad do not
function when you select Single Cell Platform
even if you have a 6-Position Cell Holder
installed in the sample compartment.
• Manual 6 - You can take up to six measurements
without changing the samples in the cell holder,
using the cell position buttons on the keypad to
advance the cell holder to the appropriate
position for the next measurement. You place
the blank in the blank position and your samples
in the other cell positions. Regardless of where
the cell holder is positioned, when you press
Measure Blank the cell holder automatically
goes to the blank position and measures the
blank. However, you can use the cell position
buttons to select a different position for the
measurement. This option is available only with
the 6-Position Cell Holder .
Note: When you have the 6-Position Cell Holder
installed, the instrument always considers
the material in the B position as a blank.
This means that even after measuring your
blank the first time, you can place
unknowns only in positions 1 through 5.
The two automatic measurements (Auto 6 and
Auto 3) are available only for instruments with the
6-Position Cell Holder. However, if you have one of
these models, you can also choose to take
measurements manually. Each test section later in
this chapter includes specific instructions on how to
take measurements automatically and manually.
Saving tests
When you power-down the instrument, the current
test is maintained by battery back-up. This means
that when you turn the instrument on again, the cell
holder alignment and values for all parameters will
be the same as they were when the instrument
was last used. When you load a test that has been
saved, the values for all parameters stored with
that test will replace the current values for the test
parameters.
As you create customized tests and collect data,
you will be saving tests for later use. The
spectrophotometer uses test files to contain the
values for all the parameters needed to run a test,
including the alignment of the cell holder and the
other parameters for the accessories installed.
Once you select the values for the parameters, you
Using “General Tests” Software
3-5 BioMate 3 Operator’s Manual