Hach DR/700 - Page 702

81-28
PHOSPHORUS, REACTIVE, continued
16. Place the
prepared sample into
the adapter with the
Hach logo facing the
front of the
instrument.
17. Press: READ
The display will
count down to 0.
Then the display will
show the results in
mg/L PO
4
3-
.
CALIBRATION PROCEDURE
1) If the DR/700 is on and in a pre-programmed method, proceed to Step
3. If it is off, press the
I/O key. The upper display will show the
wavelength and the lower display will show the module installed and the
software version number. Verify that filter module 81.01 is installed.
2) After 2 seconds, the display will show a concentration format, a
program number and the ZERO prompt.
3) Press the
PROGRAM key to obtain program number 81.000. The
ZERO annunciator will flash.
4) Press the
CAL key. The S1 annunciator and the first digit on the left
will flash
5) Press the
UP ARROW key to set the first digit to 0. When correct, press
the
RIGHT ARROW key to select the next digit. Repeat this procedure until
all four digits are set to 0.
6) Press the
RIGHT ARROW key until the decimal point flashes. Press the
UP ARROW key to move the decimal point so the display reads 0.000 for
PO
4
3-
.
7) Press the
RIGHT ARROW key. A units indicator will flash. Press the
UP ARROW until mg/L is displayed.
8) Prepare a demineralized water blank in a sample vial. Cap the vial and
put it into the DR/700.