Types of verifications, Verification procedure with a wet standard, Prerequisites for dry standard use – Hach-Lange FILTERTRAK FT 660 sc Basic User Manual User Manual
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Types of verifications
Wet or dry standards can be used to do calibration verifications.
To do a wet standard verification, refer to
To do a dry standard verification, refer to
Prerequisites for dry standard
on page 12 and then either:
•
Verification with a dry standard and software
on page 13—Applies
to instruments with dry standard software.
•
Verification with a dry standard without software
on page 15—
Applies to instruments that do not have dry standard software.
Verification procedure with a wet standard
Wet standard verification is done using 1 L of StablCal Stabilized
Formazin Certified Standard (0–5500 mNTU) for this instrument . Do not
use other standards. Do not use user-prepared formazin.
Note: For the best verification results, clean the instrument before doing a wet
standard verification. Refer to
Note: On the sc controller, there is no option to set the pass or fail criteria (PFC)
for a wet verification. The default PFC is ± 50 mNTU (0.050 NTU) or 5% of the
reading, whichever is greater.
1. From the Main menu, select Sensor Setup, [Select Sensor],
Calibrate, Verification, Perform Ver.
2. Select the available Output Mode (Active, Hold or Transfer) from the
list box and confirm.
3. Select WET for the verification type and confirm.
4. Enter the turbidity value that is on the label of the StablCal Standard
bottle and confirm.
5. When the display shows "DRAIN AND CLEAN BODY. ENTER TO
CONT.", fully flush the body of the instrument with water that is less
than 50 mNTU (0.05 NTU).
a. Remove the head assembly and bubble trap cover from the body
of the instrument. Refer to
b. Put an empty container under the instrument.
c. Remove the drain plug from the bottom of the body of the
on page 6.
Note: There is no risk of laser exposure with the drain plug removed. The
laser is disabled when the head assembly is removed.
d. Fully flush the body of the instrument with water that is less than
50 mNTU (0.05 NTU).
e. Install the drain plug in the instrument.
6. Prepare the StablCal standard. Refer to
on page 10.
7. Put a funnel at the end of the bubble trap and slowly put the StablCal
Standard in the funnel to fill the body. Confirm. Refer to
on page 11.
8. Put the bubble trap cover and head assembly on the body of the
instrument.
9. When the turbidity reading is stable (and after greater than
5 minutes), confirm to accept the reading.
10. If "GOOD VER" (good verification) is shown:
a. Select ENTER INITIALS and confirm.
b. Enter operator initials and confirm.
c. Select RETURN SENSOR TO MEASURE MODE and confirm.
11. If "BAD VER" (bad verification) is shown:
a. To do the calibration verification again, confirm.
Note: If the verification fails two times, “Please Recalibrate” is shown, then
the display returns to the Calibrate Menu. Verification cannot be done until
the instrument is recalibrated.
b. To exit, push BACK.
Note: The bad verification is saved in the verification history.
Prerequisites for dry standard use
In order to use the dry standard, the instrument must have a special
aperture plate. Refer to
on page 14. The instrument can also
have a software upgrade to install dry standard software.
Instruments made before April 2008 do not have the special aperture
plate. Customers can order and install the special aperture plate.
Installation instructions are provided with the aperture plate.
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