Calibration And Verification History; Maintenance - Hach FT660 sc Basic User Manual

8. When the instrument reading is stable, record the value.
9. Do step 7 again.
10. When the instrument reading is stable, record the value.
11. Calculate and record the average of the three recorded values. The
average value is the final baseline value for the dry standard for this
specific instrument.
12. Near the final baseline value, record the serial number of the
instrument and the serial number of the dry standard. Refer to
Figure 8 on page 14.
Note: The final baseline value for the dry standard is applicable only for the
combination of the dry standard and the instrument used to measure the dry
standard.
13. Remove the dry standard from the instrument.
a. Remove the head assembly from the body of the instrument.
1
b. Turn the dry standard /
8
remove the dry standard from the aperture plate.
c. Put the head assembly on the body of the instrument.
14. Put the dry standard in the protective case.
Verification procedure with dry standard without software
1. Do steps 1– 5 of Assign a baseline value to the dry standard
on page 15.
2. When the instrument reading is stable, record the value.
3. Use Table 1 on page 15 to identify the result and what action should
be done.
Note: Table 1 on page 15 assumes a PFC (pass or fail criteria) of ± 5 mNTU.
4. Remove the dry standard from the instrument.
a. Remove the head assembly from the body of the instrument.
1
b. Turn the dry standard /
8
remove the dry standard from the aperture plate.
c. Put the head assembly on the body of the instrument.
5. Put the dry standard in the protective case.
16 English
of a turn counter-clockwise, then
of a turn counter-clockwise, then

Calibration and verification history

The calibration and verification history logs contain information on the
last 12 calibrations and the last 12 verifications.
To access the calibration history logs, select Sensor Setup, [Select
Sensor], Calibrate, Cal History.
To access the verification history logs, select Sensor Setup, [Select
Sensor], Calibrate, Verification.
Push confirm to move through a history log. After all 12 entries are
shown, the display goes back to the menu. Push BACK to go back to
the menu.
A verification history entry shows the:
• Value of the certification standard used
• Turbidity reading at verification
• Operator initials
• Date and time
A calibration history entry shows the:
• Gain value
• Operator initials
• Date and time
Notes:
• History data is saved as first in, first out. When a history log is full, the
newest entry is saved and the oldest entry in the log is deleted.
• When the instrument is received from the factory, default values or
blank spaces are shown for the history information. Those values are
replaced with real data as the history log is filled.

Maintenance

D A N G E R
Multiple hazards. Only qualified personnel must conduct the tasks
described in this section of the document.