Sper Scientific 850045 Dissolved Oxygen - DO Pen - Manual (Page 5)

CALIBRATION
5
Calibration
1. Fill the D.O. meter probe head (completely) with
Electrolyte prior to using the first time. Please refer to
the Probe Maintenance section (page 10) for
instructions.
2. Prior to taking measurements, the D.O. meter should be
calibrated using the following steps.
3. Remove the red protective cover (Fig., 1-7) from the
black probe head (Fig., 1-5). *The small sponge inside
the red cover keeps the diaphragm moist with water.
4. To turn the meter on, press the Power On/Off button
(Fig., 1-2).
5. The LCD display (Fig., 1-1) will show %O
2
and
Temperature - see example below.
Wait for approximately three (3) minutes until the upper
display value stabilizes.
%O 2
21.5
25.9 ºC