Sondes
Section
2
YSI Incorporated
Drinking Water Monitoring Systems Operations Manual
2-66
If “Auto sleep” is
deactivated
, the sonde runs continuously no matter what sample interval has been
selected. Under these conditions, the user retains manual control of the free chlorine calibration
routine, viewing the stabilization of the readings in real time and confirming the calibration with
keyboard entries.
If “Auto sleep” is
activated
, the sonde will ‘warm up’ the sensors for the period of time selected for
the free chlorine sensor. Under these conditions, the user loses manual control of the free chlorine
calibration routine. Free chlorine will automatically calibrate after the selected time for warm up of the
Cl2 sensor has expired. In this mode of calibration, you do not
observe stabilization of the readings in
real time, but instead will observe a countdown of the warm up period followed by a message
indicating that the free chlorine calibration is complete.
Only the calibration of free chlorine is affected by whether “Auto sleep” is on or off; the user retains
manual control of the calibration of all other parameters regardless of the “Auto sleep” setting. Once a
particular warm up time (in seconds) has been utilized in free chlorine calibration, the length of that time
should not be changed during a study. A new calibration should be performed whenever the value of the
warm up time is altered.
From the Main sonde menu select
2-Calibrate
. The
Calibrate menu will be displayed. Only the enabled
parameters will be available for calibration.
CONDUCTIVITY
Select
1-Conductivity
to calibrate the conductivity probe and a second menu will offer you the options of
calibrating in specific conductance, conductivity, or salinity. Calibrating any one option automatically
calibrates the other two. After selecting the option of choice (specific conductance is normally
recommended), you will be asked to enter the value of the standard used during calibration. Be certain that
the units are correct. After pressing
Enter
, you will be able to follow the stabilization of the readings and
confirm the calibration when the readings are stable by pressing
Enter
as instructed on the screen. Then,
as instructed, press
Enter
again to return to the Calibrate menu.
FREE CHLORINE WITH FOR UNATTENDED STUDIES WITH INTERNAL LOGGING OF DATA
NOTE CAREFULLY:
The 6572 free chlorine sensor MUST be calibrated
in situ
, i.e. in flowing drinking
water whose free chlorine content has been determined by an independent method. In many cases, the
independent method involves the use of the DPD Colorimetric Method as defined in Section 4500-Cl G of
Standard Methods for the Examination of Water and Wastewater
. Relatively inexpensive colorimeters,
such as the YSI Models 9000 and 9100 and the Hach Model 5870000, are available for carrying out the
DPD method to determine the free chlorine in the effluent of the flow cell associated with the 6920DW or
600DW-B drinking water studies.
---------------Calibrate--------------
1-Conductivity 6-ISE3 NH4+
2-Free Cl2 7-ISE4 NO3-
3-Pressure-Abs 8-ISE5 Cl-
4-ISE1 pH 9-Turbidity
5-ISE2 ORP A-Chlorophyll
Select option (0 for previous menu):