YSI 600DW-B Sonde - Manual (Page 72)

Sondes Section 2
----------------Logging----------------
1-Interval=00:15:00
2-Next at 07/17/96
3-Next at 18:00:00
4-Stop at 07/31/96
5-Stop at 18:00:00
6-File=clrlake3
7-Site=Clear Lake at Spillway
8-Bat volts: 9.0
9-Bat life 21.2 days
A-Free mem 18.9 days
B-Stop logging
Select option (0 for previous menu):
The display now shows the next date and time for logging and the stop date and time for the logging study.
Most importantly, note that the bottom command now shows
B-Stop logging, a confirmation that the
logging has indeed been initiated.
The Unattended study will terminate when the duration you specified has expired or the batteries are
expended. If you want to terminate sooner, simply select
2-Unattended sample from the Run menu, then
B-Stop logging. Select 1-Yes and return to the Unattended setup menu.
Stop logging?
1-Yes
2-No
Select option (0 for previous menu):
2.9.2 CALIBRATE
All of the sonde sensors (except temperature) require periodic calibration to assure high performance.
However, the calibration protocols for free chlorine are significantly different depending on whether the
sonde is being set up for spot sampling or longer term unattended monitoring studies. This difference is
user-selectable and is required primarily because the optimal performance of the free chlorine sensor
cannot be attained unless the control of this sensor varies from short term to long term applications.
For spot sampling it is best to pulse the sensor continuously during the Run mode to attain the most
accurate results and optimize the response time. However, this continuous pulsing is not ideal for longer
term logging studies in which the sonde data is captured to sonde memory or to a data collection platform
at much less frequent intervals (e.g. 15 minutes). Continuous pulsing not only shortens the time between
required probe maintenance, but consumes more power. With proper selection of the “Auto sleep” option
(discussed in detail in
Section 2.9.8, Advanced Menu), the user can configure the sonde software to either
run continuously or “go to sleep” between samples to minimize free chlorine probe wear and conserve
power. The effect of this choice on the user interface relative to free chlorine calibration is significant as
described below:
YSI Incorporated Drinking Water Monitoring Systems Operations Manual 2-65