
Chapter 8
Maintenance & troubleshooting
58
Osmo1
®
Single-Sample Micro-Osmometer User Guide
To replace the sampler plunger wire:
1.
Unscrew the calibration gauge and key.
2.
Rotate the sampler shaft until the calibration
setscrew appears beneath the access hole in the side
of the sampler body.
3.
Place the key end of the calibration gauge in the
access hole and turn counter-clockwise to loosen the
setscrew.
4.
Carefully remove the old sampler plunger wire.
5.
Place a sampler tip on the sampler to help you place
new wire correctly.
6.
Slip the sampler plunger wire into the sampler tip so
the Teflon plunger tip protrudes about 1/16" or
1.6 mm from the end of the sampler tip.
NOTE:
If the sampler plunger wire cannot be placed
into the sampler tip without using excessive
force, follow the instructions under “Fixing a
too-tight fit” on page 58.
7.
Using the key end of the calibration gauge, push the
sampler plunger wire into the sampler as far as it will
go.
8.
Tighten the calibration set-screw with the calibration
gauge.
9.
Screw the calibration gauge and key back into the
top of the sampler.
Your 20-
μ
L sampler is now calibrated and ready to use.
NOTE:
For best results, follow the instructions under
“Verifying the sampler calibration” on page 58
to confirm that the sampler is calibrated correctly.
Fixing a too-tight fit
1.
Place the wire end into the back end (large
diameter) of the sampler tip (Figure 89).
Sampler tip
Sampler
plunger
wire tip
Figure 89: Placing the wire end into the back end of the sampler tip
2.
Install the sampler plunger wire and tighten.
3.
Move the sampler tip in a back-and-forth motion
over the plunger wire and tip until the fit is
acceptable.
4.
Remove both parts and re-assemble normally.
Verifying the sampler calibration
Perform this verification procedure after you replace the
sampler plunger wire, or any time you want to confirm
that the sampler is calibrated correctly.
1.
Place a new sampler tip on the sampler.
2.
Unscrew the calibration gauge and key.
3.
Insert the key end of the calibration gauge into the
sampler tip.
4.
Visually inspect the position of the end of the
sampler plunger wire tip and the end of the
calibration key.
NOTE:
There should be no gap between the two.
5.
If necessary, reset the sampler plunger wire as
described above.