Teledyne 4250 Installation And Operation Manual page 73

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
Absolute barometric pressure is barometric pressure not
corrected to sea level. The barometric pressure published by
the U.S. Weather Bureau is adjusted to sea level. If you use their
value, you must convert it to the absolute pressure for your
altitude. You should use Weather Bureau barometric pressure
only if you are at sea level, or are able to correct the Weather
Bureau figure to absolute pressure at your location. Enter the
correct value.
WRAP D. O. PROBE IN MOIST CLOTH
PRESS ENTER WHEN STABLE: X.XX MS/CM:
Then the display will advance to the following:
CALIBRATING...
PLEASE WAIT...
If you select ALTITUDE for D.O., this will appear:
UNITS FOR ALTITUDE ENTRY
• FT • • M •
4250 Flow Meter
Section 2 Programming
X.XX pH
2-45