Sondes
Section
2
YSI Incorporated
Drinking Water Monitoring Systems Operations Manual
2-75
time. After the readings have stabilized, press
Enter
to confirm the calibration. Then, as instructed, press
any key to return to the Calibrate
menu.
Select the
3-point
option for maximum accuracy over the entire range of 0 to 200 ug/L. As for the 2-point
procedure, one of the standards must be 0 NTU. The procedure for this calibration is the same as for a 2-
point calibration, but the software will prompt you to place the sonde in the additional solution to complete
the 3-point procedure.
For all rhodamine calibration procedures, be certain that the standard and sensor are thermally equilibrated
prior to proceeding with the calibration.
REESTABILISHING DEFAULT CALIBRATION – “UNCAL” COMMAND
If, for any reason, you want to return to the factory default settings (slope and offset) for any parameter,
follow the instructions below:
•
Activate any calibration screen (1-point, 2-point, or 3-point) where a numerical entry is requested. In
the example below, a 2-point turbidity calibration was selected.
•
Instead of entering a numeric value, type the word “uncal” and press
Enter
.
•
An “uncal” entry at any calibration prompt will reset both slope and offset for this parameter to the
factory default settings.
NOTE:
When using the 650 MDS as the sonde interface device, the “uncal” operation is performed by
holding the
Escape
key down and then pressing the
Enter
key. See
Section 3
of this manual for more
details.
---------Turbidity calibration--
-------
1-1 point
2-2 point
3-3 point
Select option (0 for previous
menu): 2
Enter 1st Turbid NTU:uncal
