5 Measurement of dissolved oxygen
5.1 Preparation of the oxygen electrode (first filling and top-up)
Storage
solution
Unscrew the sealing screw
from the refill opening
Fill the sensor completely
with KOH via the refill
opening
5.2 Calibration of the oxygen electrode
Due to the ageing of the sensor, the oxygen sensor must be calibrated regularly.
To do this, the instrument features easy-to-use calibration functions. We recommend
carrying out calibration every seven days or so, or immediately before measurement
in order to ensure the greatest possible measuring accuracy.
Please note the instrument setting for calibration:
• In the configuration menu, select the appropriate calibration medium: air (Air) or water
(AqUA) (<SEt PArA>: CAL).
• In the configuration menu, set whether 1-, 2- or 3-point calibration is to be performed
(<SEt PArA>: CAL.P)
SD_315_DO_1 06/2020
The sensor is supplied dry and must be filled before first use! Take
care when working with KOH. The electrolyte is corrosive.
Avoid contact with the skin and protect the eyes! *Suitable gloves
according to DIN EN 420, for example made of natural latex, na-
tural rubber, butyl rubber, nitrile rubber, polychloroprene, or fluo-
rinated rubber.
Remove the membrane
head by twisting it
Remove any air bubbles by
tilting gently
Fill the membrane head to
3/4 full with KOH
Close the refill opening
with the sealing screw
Screw the membrane head
firmly in place
Before first use: store the sensor
for 2 hours in the storage flask
(filled with distilled water)
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