Calibration Reminder; Calibration Data Memory; Measurement Of The Dissolved Oxygen - Tintometer Lovibond SD 315 Oxi Mode D'emploi

A sodium sulphite solution can be prepared as the zero reference [0%] for both CAL Air
and CAL AqUA. To do this, dissolve 1 g sodium sulphite in 1 litre water and wait around 20
minutes until all the dissolved oxygen has been removed.
1) Start of calibration: Press the <CAL> button for 3 seconds
2) Calibration point 1: (Pt. 1)
For 3-point calibration, first 0% O
created.
The display shows Pt. 1 and the relevant reference:
• ZERO for 0% O
• O.2 for 100% O
If the display flashes, no valid reference has been recognised. As soon as the measurement
values for oxygen and temperature are constant, the calibration of the first point is auto-
matically completed.
3) Calibration point 2: (Pt. 2)
The display shows Pt. 2 and the relevant reference:
• Air for ambient air or AqUA for air-saturated water
• O.2 for 100% O
• ZERO for 0% O
For 2-point calibration, the calibration is ended and a sensor evaluation is then displayed in %.
4) Calibration point 3: (Pt. 3)
The display shows Pt. 3 and the last reference. As soon as the measurement values are cons-
tant, calibration is automatically completed and a sensor evaluation is then displayed in %.

5.3 Calibration reminder

Set a reminder to regularly check the calibration data (<SEt PArA>: C.int).
The time interval chosen depends on the use and stability of the electrode.
As soon as the interval expires, >CAL< flashes in the display as a reminder.

5.4 Calibration data memory

The last 16 calibrations, with information on the measurement result and time stamp,
are stored in the instrument. Stored calibration data can be read both with the PC software
GSOFT3050 or in the <rEAd CAL> menu (see Chapter 4.3).

5.5 Measurement of the dissolved oxygen

Before each measurement, check whether any salinity correction is required.
The content of dissolved oxygen in an aqueous sample is greatly influenced by the salt
content (see Chapter 5.7).
SD_315_DO_1 06/2020
, and for 2-point calibration 100% O
2
2
(pure oxygen or oxygen-saturated water)
2
(pure oxygen or oxygen-saturated water)
2
2
or 0% O must be
2 2
49