It is sometimes helpful to validate the Phosphax’s measurement readings against a standard. The Phosphax does not use routine calibrations using non-zero standards like many other probes.
Instructions for a verification are given on page 43-45 of the PHOSPHAX USER MANUAL (US ENG Phosphax sc, Phosphax Indoor sc Analyzer User Manual_DOC026.53.00026
) and is copied below.
• Blind plug LZY193 (Plugging set LZY007)
• Beaker (for example 150 mL)
• Standard solution for validation
Follow the internal menu steps for the validation.
1. From the MENU select SENSOR SETUP>PHOSPHAX SC and press ENTER.
2. Select MAINTENANCE>TEST/MAINT>VALIDATION>DISCHARGE.
3. Enter the number of measurements which should be discharged before starting the measurements of the validation. (Default value: 2; value range: 1 to 5)
4. Select NUMBER OF MEAS..
5. Enter the number of measurements which should be used for the validation measurements. (Default value: 3; value range: 2 to 10)
6. Select START after adjusting both parameters and the analyzer is going into the service state. The remaining time is displayed in seconds. The OUTMODE is set to HOLD.
7. Select ENTER to modify the analyzer (Figure 19 on page 45):
a. Unscrew the fitting (item 2) of the sample tube (item 5) which connects the overflow vessel (item 1) and the valve block (item 4) at the overflow vessel.
b. Screw in the blind plug (item 3) in the thread of the overflow vessel (item 1) and insert the sample tube in a beaker (for example 150 mL) with standard solution for the validation. Note: To receive stable measurement values, close the door of the analyzer.
8. Press ENTER to start the validation. Note: The remaining time is displayed in seconds:
9. Press ENTER to escape. The results are displayed to note down.
• The discharge value and the Conc value are counted down to zero.
• The validation is finished when the process shows the service mode and the remaining time is 0 seconds.
• For the adjusted number of validation measurements, the values are listed and the calculated average of this value is displayed.
Note: The data log records the validation values and average value from the analyzer.
10. Press ENTER to proceed. Note: Press START to confirm the inquiry to return to the measurement process or to the service mode.
11. Select ENTER and modify the instrument to the original analyzer configuration.
12. Start the measurement mode or hold the service mode.