YSI 9500 Photometer - Manual (Page 14)

3 During the display period, the same options are available as at the end of a
normal test program. Select ‘Return’ from the ‘options menu' to take the
program back to the start of the first stage of a multiple test procedure to
enable further samples to be tested for the same parameters.
Some continuation test procedures involve a standing period. The photometer
may switch off automatically during this time. To avoid the instrument
switching off, use the timer function to time any standing period. The timer will
over-ride the auto switch off function.
Favorite Tests List
The four most recently used tests are listed at the top of the 'Choose a Test'
screen for convenience.
Expressing Different Chemical Forms
If the test result can be expressed in different chemical forms, the chemical
symbol will have flashing and
to indicate this. Use the the and keys
to step through the options available.
Reading in Transmittance and Absorbance
When taking readings in Transmittance or Absorbance mode, use the and
keys to step through the wavelengths until the required wavelength is reached.
Timer
The photometer features a countdown timer with alarm as an aid to carrying
out test procedures. The timer can be accessed at any time by selecting
‘Timer’ from the ‘Options’ menu.
The following display will appear :-
Timer
00:00
EXIT
Key in the time required in minutes and seconds, maximum 29 minutes and
59 seconds, using the numerical keys, then press [OK] to start the timer. Use
the and keys to reposition the cursor and re-enter the time if it is keyed in
incorrectly.
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