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<5. Calibration of the Instrument for Measurement Analysis>
5-5
IM 12Y18A04-01EN 1st Edition : Oct. 04, 2019-00
5.10.1 Cell Wash
In cell wash, the sample is pumped into the reaction cell. The user is allowed to edit the volume of
the sample to be pumped by the parameter called CELL WASH VOLUME. To edit the cell wash
volume, from the MAIN MENU follow the sequence:
MENU → SETUP → METHOD → CELL WASH VOLUME
In cell wash volume, the positive volume is to pump the sample into the reaction cell, and the
negative volume is to pull back an amount below the drain after the cell wash is completed.
During the cell wash, the stirrer is on and the info field (if enabled) shows the sample pumping
progress with a progress bar, along with the volume pumped.
5.10.2 Sample Capture
In the sample capture step, the stirrer is switched off and fluid is allowed to settle for 5 seconds to
drain any excess from the reaction cell overflow drain.
During the sample capture, the info field (if enabled) shows the 5 seconds countdown.
5.10.3 Optics Testing
In optics testing, the system checks the optical path and status of the LED source.
During this stage in the cycle, the info field (if enabled) shows the test optics progress bar which
times out at a maximum period of 90 seconds.
NOTE
Optics test may flag the following error messages:
“TESTING OPTICS, PLEASE CHECK FOR OPTICS FAILURE”
Optics test failed due to the non-functionality of the LED source or detector, measurement is
aborted, and the info field will flash the error message.
“TESTING OPTICS PLEASE CHECK FOR STRAY LIGHT”
Stray light reading outside the allowed limits: will flash with a warning message.
“TESTING OPTICS LOW SIGNAL LEVEL . . . CELL MAY BE COATED AND MAY REQUIRE
CLEANING“
If the test determines that the light energy reading is outside the allowed limits, the measurement
is aborted. The cell may require cleaning, or you many need to re-calibrate the optics.
5.10.4 Checking Reaction Temperature
When reaction cell temperature control is enabled, at this stage in the cycle the reaction cell
temperature is tested against the set point.
To enable or disable the REACTION TEMPERATURE CONTROL, from the MAIN MENU follow
the sequence:
MENU → SETUP → METHOD → REACTION TEMPERATURE CONTROL
If reaction temperature control is enabled, then the temperature set point is editable. To edit the
temperature set point, from the MAIN MENU follow the sequence:
MENU → SETUP → METHOD → REACTION TEMPERATURE
The temperature stabilization is attained through PID control. Once it reaches the set point,
it stays almost at the same temperature, until and unless the reaction temperature control is
disabled or set point is altered.
This test is allowed a maximum of 240 seconds for the reaction cell to attain the set temperature.
If it does not reach stability or set point in the allowed time, it will flag a warning message and
proceed to the next step. The info field (if enabled) shows the temperature progress bar.