Hach FT660 sc, Basic User Manual

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7. Put the bubble trap cover and head assembly on the body of the
instrument.
Note: If the head assembly is not correctly installed, the laser will not turn on
and the reading on the display will be near 0.000 mNTU or a negative value.
The red status light on the instrument will also flash one time per second.
8. When the turbidity reading is stable (and after greater than
5 minutes), confirm to accept the reading.
9. When the display shows "GOOD CAL! GAIN: X.XX ENTER TO
CONT.", confirm to save the turbidity value.
Note: If the display shows "BAD CAL!", confirm to do the calibration again or
exit.
10. When the display shows "VERIFY CAL?", confirm to do a calibration
verification or exit without verification.
11. Do a calibration verification or enter the operator initials to complete
the calibration.
12. When the display shows "RETURN SENSOR TO MEASURE
MODE", confirm.
Figure 7 Calibrate the instrument
1 Head assembly 4 Funnel
2 800 mNTU StablCal
®
Certified
Standard
5 Body of the instrument
3 Bubble trap 6 Bubble trap cover
Calibration verification
Do a calibration verification immediately after every calibration.
Subsequent verifications are referenced to the initial verification.
Do a calibration verification monthly between calibrations.
A calibration verification is a check that is done to make sure that the
instrument is working correctly and calibrated.
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