Hach sension6, Instruction Manual, Page: 37 / 86

36
SECTION 3,
continued
3.2 Calibrating the Meter
The sens
ion
6 Dissolved Oxygen meter must be calibrated prior
to use. Prior to calibration, the probe must be prepared and
stabilized. For measurements below 1 mg/L DO, the probe should
be zeroed prior to calibration. See
Section 3.3.3 Zeroing the
Probe .
The calibration may be performed in three ways:
•
Calibration may be performed in a water saturated air
environment with a known barometric pressure and/or
altitude. See
Section 3.3.4 .
OR
•
Calibration may be performed using a water sample that has a
known dissolved oxygen concentration in mg/L. The sample
concentration is determined by another technique such as a
Winkler titration. See
Section 3.3.5 .
OR
•
Calibration may be performed by setting a water sample to
100% saturation. See
Section 3.3.6 .
3.3 DO Probe
3.3.1 Probe Assembly
1. Remove the membrane protector from the membrane cap
without covering the hole as the protector is pulled off
(
Figure 7 ).
2. Hold the membrane cap in a vertical position.
3. Fill the membrane cap about 2 /
3
full with Dissolved Oxygen
Electrolyte Filling Solution.
4. While holding the DO probe vertically with the tip pointing
down, gently screw the module cap onto the tip. Electrolyte
should leak out of the threads.