
18
A
dvanced
S
ensor
T
echnologies,
I
nc. U.S.A.
Website:
www.astisensor.com
IOTRON
TM
Trademark of ASTI
IOTRON
TM
pH / ORP / ISE / DO / Conductivity Measurement Products Lines
“Auto Calibrate D.O. Sensor” Menu - Temperature
You need to select the channel for which you wish to
perform the fully automated dissolved oxygen sensor
calibration. If you are not sure prefer to the main
screen as it will display on what channel D.O. sensor(s)
have been configured.
The usual caveats apply before performing calibration
on you dissolved oxygen (D.O.) sensor. The channel
that will be calibrated should be placed on hold prior to
performing the calibration especially if the values
obtained from the sensor are used for any type of real-
time closed loop control purposes.
The D.O. sensor should be at thermal equilibrium
before proceeding and be clean and dry, suspended
over a source of water in cases of low humidity at the
location where the sensor is to be calibrated.
The TEMPERATURE should always be CALIBRATED
FIRST on the dissolved oxygen sensor. The reason is
that the temperature is used as the main basis of
obtaining the dissolved oxygen ppm value for the
current dry in air condition used as the basis of the
automated calibration routine. If the temperature is not
stable before proceeding and not well calibrated you
can obtain suboptimal results when calibrating the D.O.
sensor in the field.
Finally after the dampener time is expired the new
temperature calibration results will be shown and the
time since calibration will show as 0.00 days. Following
the instructions on the following page to proceed onto
the calibration of the dissolved oxygen ppm reading for
the process value next.