Teledyne 4220 Installation And Operation Manual page 65

over 14%!
Errors in level measurement have a greater effect on flow cal-
culations at low liquid levels. Dimensional errors tend to be
more significant at higher levels.
If you select pH for Parameter to Adjust, the following display
will appear. (Note that pH will not appear as an option unless
you have selected it in step 1.) If you want to measure pH and pH
does not appear in this step, you must go back to step 1 and
select pH instead of NOT MEASURED.
pH CALIBRATION
• pH 4 & 7 • • pH 7 & 10 • • pH 4, 7, & 10 •
You can perform a two- or three-point calibration for pH with the
pH sensor. Select the calibration that best suits your stream's
profile. If the pH in your stream in generally below 7, you would
probably select pH 4 & 7. If the pH is generally above 7, you
would probably select pH 7 & 10. If your stream's pH varies a
great deal, say from 3 to 12, your best choice would be pH 4, 7, &
10. Then:
RINSE PROBE AND PLACE IN 4.0 pH SOLUTION
PRESS ENTER WHEN STABLE
The flow meter will direct you to repeat this process with the
other standard buffers (7 and/or 10) to calibrate the pH sensor. If
the probe fails to provide the correct output with any of the
buffer solutions, you will receive the following message:
pH BUFFER/PROBE OUT OF RANGE
PRESS ENTER TO CONTINUE
If you select D. O. for Parameter to Adjust, the following display
will appear:
DISSOLVED OXYGEN CALIBRATION
•D.O. STANDARD••ABS BAROMETRIC PRESSURE•>
ALTITUDE is just off screen to the right. If you select D.O.
STANDARD for the calibration method, the following display
will appear:
D.O. STANDARD
0.00 MG/L
If you select ABS (absolute) BAROMETRIC PRESSURE the fol-
lowing will appear:
ABS BAROMETRIC PRESSURE
X.XX mmH g
4220 Flow Meter
Section 2 Programming
X.XX pH
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