PyroTec™ PRO Hardw are User’s Manual, V1.2
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RT-MN024-1.2 02/21
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Appropriate message if no liquid or not enough liquid available for sampling
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Software controlled, constant submerge depth during aspiration and dispensing
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Enabling clot detection
5.4.2 Clot Detection
How Does it
Work?
The clot detection is based on the liquid level detection. The application software moni-
tors the exit signal while the tip is retracted after aspiration of a liquid and compares the
level at which the exit signal appears with the liquid level detection value.
In the following the function of the clot detection and its limits are scrutinized.
Sample aspiration
1)
The tip detects the liquid level.
2)
The tip moves down into the liquid to
the specified submerge depth (S).
3)
The tip aspirates a sample while con-
tinuously maintaining the submerge
depth (called “tracking”).
The application software calculates the
theoretical level of the liquid surface after
aspiration.
If There Are
No Clots
No clot detected
After aspiration:
1)
The tip retracts from the sample.
Normally, i.e. if there is no clot, the exit sig-
nal is detected shortly after passing the
level of the calculated liquid surface.
This delay is caused by adhesion forces that
make the liquid stick to the tip.
2)
The clot detection checks if the exit
signal is within a predefined limit (L).
3)
The tip is still within the limit after
detection of the exit signal.
No error message will be generated.
A
Tip
B
Liquid level
C
Sample
D
Tube
E
Original liquid level
F
Liquid level after aspiration
S
Submerge depth
