Teledyne Foxy R1, Инструкция по эксплуатации

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Foxy
®
R1 and Foxy
®
R2 Fraction Collectors
Section 3 Programming
3-12
Use this display to set the fraction volume—expressed as a
number of drops, and the flow delay volume—expressed as
time.
2. Ensure that the fraction volume setting is active as indi-
cated by the Volume Select icon. That is, the tube should be
highlighted with a border. If not, touch the icon to toggle
the setting.
3. Enter the fraction volume as 1 to 999 drops using the
arrow icons. The Up and Down Arrows increment or decre-
ment the numbers, the Left and Right Arrows move the
cursor position.
4. Touch the Volume Select icon to display the Flow Delay vol-
ume. The hourglass should be highlighted with a border.
5. Enter the Flow Delay volume as hours, minutes, and sec-
onds using the Arrow icons. The Up and Down Arrows
increment or decrement the numbers, the Left and Right
Arrows move the cursor position.
6. Touch the Enter icon to return to the Methods Settings
menu.
About Flow Delays
A Flow Delay synchronizes the tube changes with
sample flow to make precise peak cutting possible. The
flow delay time is the time required for a fraction to
travel from your detector to the fraction collector’s drop
former. The delay depends on the flow rate and the
size of the tubing between the fraction collector and the
detector.
To calculate the flow delay time, use this formula:
T = V

Q
Where T is the delay time in seconds, V is the internal
volume of the tubing, and Q is the flow rate, (in the
same units as V) per second.
The volume of the tubing can be calculated by:
V =
 
4

D
2 
L or expressed as:
V= 0.7854

D
2 
L
where L is the tubing length (cm) and D is the inside
diameter (cm). The resulting volume is in milliliters.
An easy, alternative way to find the delay time is to
introduce a bubble ahead of the detector and measure
the delay to the drop former.