Siemens ADVIA 2400, Operator'S Manual, Page: 21 / 200

System Overview 21
After the sample is dispensed, the SPP moves back to the wash port, where its inside is
washed. Sample probe valve (SPEV1) opens, allowing the SCP to send degassed water
through the SPP’s inside.
After the wash, the water drains down the wash port.
Clot detection
The clot detection system utilizes a pressure transducer to monitor the pressure in the
sample dilution probe line (DPP) for a complete obstruction during the sample aspiration
and dispensation cycle. Clot detection is available on the DPP line only.
The system monitors the pressure at the transducer at four points during the sampling
cycle and will display an error if a predefined limit is exceeded at any of the checkpoints.
A fifth check occurs at the start of sampling.
•
Clot detection can be toggled on and off.
•
Clot detection can be deactivated for calibrator and control materials that are run
from the STT or CTT.
•
Clot detection is active for samples run from the STT, CTT, rack handler or other
LAS device. Clot detection is inactive when the DPP aspirates from the DTT.
The clot detector is active each time the DPP probe enters a sample, even when multiple
aspirations are required. If a sample is to be aspirated three times, the DPP will make all
three aspirations, even if a clot is detected. This may cause partial results to be reported.
When a sample is flagged for a clot, all of the ordered tests for the sample must be rerun.
Reaction tray
1)
Reaction tray (RRV)
2)
RRV cuvettes (immersed in oil
heat bath)
Figure 1- 13 Reaction tray
For each sample assay, the reagent probes (RPP1 and RPP2) dispense reagent into
cuvettes in the reaction tray (RRV). Then the sample probe (SPP) dispenses diluted
sample into the cuvettes. The mixture is then stirred by the reaction mixers (MIXR1 and
MIXR2), producing the desired reaction.
For analysis, the reaction tray rotates the cuvette in front of the spectrophotometer, where
the cuvette’s absorbance is measured. After analysis, the cuvettes are washed by the
reaction washer (WUD).