Hach 1720E, User Manual

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18
Operation
9. Stop the sample flow. Drain and clean the body and bubble trap. Fill the cylinder with
1 L deionized water. Replace the head and confirm.
Important Note: Carefully pour the DI water in such a way that minimizes any bubble
formation that would result in a false, high reading.
10. The measured reading (based on a gain of 1.0) is displayed. Confirm.
11. Enter the standard turbidity value of the user prepared standard and confirm.
12. Drain the cylinder. Pour the prepared standard into the cylinder and confirm.
13. The measured reading (based on a gain of 1.0) is displayed. Confirm.
14. The display will read GOOD CAL! GAIN: X.XX ENTER TO CONT. Confirm. (If the
calibration was unsuccessful, the display will read BAD CAL! Confirm to redo or exit.)
15. The display will read VERIFY CAL? Confirm to verify or exit without verification.
Note: If a dry verification is performed directly after a calibration, the measured value is assigned as
the expected value for future verifications (when using the dry verification device with the same
serial number). As long as the verification exists within the verification history, the expected value will
be retained. Otherwise, the expected value will be the nominal labeled value associated with the dry
verification device.
16. Select the verification type (begin at step 5 in section 5.5.3.1 on page 19 for dry
verification or section 5.5.3.2 on page 19 for wet verification) or enter initials to
complete calibration.
17. Return the sensor to measure mode and confirm.
5.5.2 Calibration with StablCal
®
Before starting the calibration, read and apply the tips in section 5.5 on page 16 .
1. From the Main Menu, select SENSOR SETUP and confirm.
2. Select the appropriate sensor if more than one is connected and confirm.
3. Select CALIBRATE and confirm.
4. Select STABLCAL CAL and confirm. Select the available Output Mode (Active, Hold,
or Transfer) from the list and confirm.
5. Enter the standard turbidity value of the user prepared standard and confirm.
6. Drain/clean/rinse the turbidimeter body or cal cylinder. Pour the 20 NTU standard into
the cylinder body. Replace the head and confirm.
7. The measured reading (based on a gain of 1.0) is displayed. Confirm.
8. The display will read GOOD CAL! GAIN: X.XX ENTER TO CONT. Confirm. (If the
calibration was unsuccessful, the display will read BAD CAL! Confirm to redo or exit.)
9. The display will read VERIFY CAL? Confirm to verify or exit without verification.
Note: If a dry verification is performed directly after a calibration, the measured value is assigned as
the expected value for future verifications (when using the dry verification device with the same