YOKOGAWA WE440, User Manual

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<5. Calibration of the Instrument for Measurement Analysis>
5-6
IM 12Y18A04-01EN 1st Edition : Oct. 04, 2019-00
NOTE
No variation in temperature for a period of 80 seconds aborts the measurement, and the info field
will flash with the error message: “PLEASE CHECK FOR HEATER FAILURE”.
If the temperature is not stabilized within 200 seconds and below the set point, then the info
field will flash with the warning message: “CHECKING THE REACTION TEMPERATURE.
TEMPERATURE BELOW SET POINT”.
If the temperature is above the set point, then the info field will flash with the warning message:
“CHECKING THE REACTION TEMPERATURE. TEMPERATURE ABOVE SET POINT”.
5.10.5 Blank Measurement
In this event, a reading is recorded called BLANK ABSORBANCE.
The stability of the recorded reading depends on the specified stability criteria. You have the
choice of editing the stability criteria. To do this from the MAIN MENU follow the sequence:
MENU → SETUP → ANALYSIS PARAMETERS → STABILITY CRITERIA
During this stage the info field (if enabled) shows the blank measurement progress bar with the
BLANK ABSORBANCE reading in AU. (This is a relative value and NOT an absolute value.)
For the phosphate measurement, the event of blank measurement and its sequence in the
measurement cycle is done before adding the third color developing reagent.
NOTE
When unstable and not meeting the stability criteria, the info field will flash with the warning
message “TAKING BLANK MEASUREMENT, UNSTABLE SIGNAL”.
5.10.6 Add Reagents
In add reagent, the reagent is pumped into the reaction cell. You are allowed to edit the volume of
the reagent to be pumped by the parameter called REAGENT VOLUME.
To edit the reagent volume, from the MAIN MENU follow the sequence:
MAIN MENU → SETUP → METHOD → (+) to go to page 2 → REAGENT VOLUME (1)
In reagent volume, the positive volume is to pump the reagent in to the reaction cell, and the
negative volume is to pump back any reagent drops in the pump delivery tube after the reagent
addition is completed. After pumping the reagent, the stirrer is turned on for an editable period of
time called STIR TIME to mix the reagent thoroughly with sample.
To edit the reagent volume, from the MAIN MENU follow the sequence:
MAIN MENU → SETUP → METHOD → (+) to go to page 2 → STIR TIME (1, 2, 3)
During the addition of reagent, the stirrer is on and the info field (if enabled) shows the reagent
pumping progress, with a bar and the volume pumped. After adding the reagent, the countdown
of stir time is also shown along with the absorbance of the sample mixture.
NOTE
If the pump is not assigned to a reagent, it will abort the measurement and the info field will flash
with the error message: “PUMP IS NOT ASSIGNED”.