VP-ITC MicroCalorimeter User’s Manual
5.4 Replacing Injection Syringes & Height
Adjustment
If you order a replacement syringe for the pipette you will need to adjust syringe height (i.e. the
position the stirring paddle in relation to the bottom of the cell). Each titration syringe comes with
a round ‘height disk’ (upper Syringe Clamp) that will ultimately determine your syringe height
once the syringe and syringe holder is inserted into the ITC sample cell. Prior to using the new
titration syringe in your ITC you will first need to properly set the ‘syringe height’. The syringe
height is the distance between the bottom of the syringe needle and the bottom of the cell, and is a
critical setting for ITC performance. The proper setting for the ITC syringe height is 3 mm off
the bottom of the cell. To make this adjustment, follow the steps outlined below:
Removing The Old Syringe From The Pipette Injector
You must first separate the Syringe Holder from the pipette
injector.
1.
Place the pipette in its stand
on the side of the instrument.
2.
Open the Setup/Maintenance menu
.
3.
From the pipette maintenance group
click
on the
Remove
Old Tip
button.
Wait for the injector plunger to move up to its home position, you
will hear a beep when the movement is complete.
4.
Separate the injector from the holder
by turning the
Locking Collar counter clock-wise.
5.
Remove the lower Syringe Clamp
using a .050” Ball Point
Hex Driver.
6.
Remove the old syringe
by using a collinear force (to
prevent the syringe needle from bending) with the Syringe
Holder.
Setting The New ITC Syringe Height
7.
Loosen the set-screw
on the upper Syringe Clamp so that the
disk is free to slide up and down on the outer diameter of the syringe glass.
8.
Position the syringe in the syringe holder
so that the tip of the syringe will not hit the
bottom of the cell when the syringe/holder assembly is inserted into the sample cell. This can
be easily accomplished
by positioning the glass of the syringe so that it is flush to the
bottom of the holder, but not lower
.
9.
Insert the syringe/holder assembly into the sample cell compartment and properly seat the
assembly into place.
10.
Gently push down on the top of the syringe until you feel it hit the bottom of the cell
. If
you are unsure then double-check it by lifting the syringe up and lowering it again until the
bottom of the cell stops it.
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