ProStar 430 Autosampler Control Manual
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03-914947-33:2
If one injection is to be made out of each vial or a wash routine
has to be performed after every injection: the needle withdraws
from the vial immediately after the injection and, if programmed,
immediately performs a wash. After the analysis time elapses a
new sequence is started.
If more than one injection is to be made out of the same sample
vial without performing a wash routine, after the analysis time
has elapsed the ProStar 430 withdraws a flush volume to
compensate for diffusion of mobile phase from the rotor groove
into the front of the sample line during the analysis time. This
flush volume between injections is not programmable and is
always 50% of the programmed flush volume. If the total
amount of sample withdrawn with the next injection from the
vial will exceed the total volume of the buffer tubing, the buffer
tubing is rinsed before the next injection. The next injection
sequence will then start with a full flush volume.
Air segment :
An air segment can be used to reduce the amount of flush
volume. This air segment is at the front of the flush volume and
will not be injected and therefore will not influence the injection.
With a standard needle the flush volume must be at least 30 µl
for injections with air segment and 35 µl for injections without
air segment. If the samples are highly viscous it may be
necessary to program larger flush volumes and reduce the
syringe speed for better performance.
Situation after filling the loop in the case of Full loop injections with
(A) or without air segment (B)
