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CASY TT Operator‘s Guide
Points to be Observed when Performing Measurements
Measuring pore blockages
During the measurement, the CASY Instrument exactly monitors the rise times of the fluid column.
This procedure ensures the reliable detection of even film-like deposits (protein, lipids etc) in the
measuring pore, which shrink rather than actually block the pore, resulting in incorrect volume cal-
culation. If the rise time exceeds a critical limit, the following error message appears:
ERROR SCREEN
TT-2AB-9999 15.04.2009 10:15
Measuring Timeout !
Capillary is possibly blocked.
Further information will be
provided by your manual.
USE ENTER TO CONFIRM.
PRESS CLEAN TO FLUSH THE LIQUID SYSTEM.
Most blockages occurring during the measuring operation result from the temporary presence of
very large particles (
e.g.
, aggregates, tissue remnants) in front of the measuring pore, which act like
a “valve flap”. You can repeat the measurement immediately after confirming the error message
by pressing
ENTER
. Shaking the CASY cup slightly often helps to remove contamination from the
outside of the measuring pore. If the blockage remains, you can usually remove the contamination
easily using the
CLEAN
function.
During the
CLEAN
cycle, fluid is flushed under pressure from inside the measuring capillary
through the measuring pore into the sample cup. To prevent your sample becoming diluted or
contaminated, replace it with a CASY cup containing freshly filtered CASY ton before you run a
CLEAN
cycle.
