User Guide

18
minutes to ensure precise
conditioning of the probe.
• Remove the protective cap
from the D.O. probe.
• Set the appropriate altitude
factor (see page 23). Make
sure the salinity factor is set
to zero (see page 25).
ZERO CALIBRATION
• Dip the probe into HI 7040
zero oxygen solution and
stir gently for 2-3 minutes.
• Press the CAL key and the "BUF" indica-
tor will blink until the reading is stable.
• As soon as the reading is stable, the
"CFM" indicator will start blinking. Press
the CFM key to confirm the "0.0%" D.O.
reading.
• If the reading is not close to the selected
value, "WRONG
BUF
1
" and "WRONG " will
blink alternatively.
CAL
%
BUF
%
CFM
%
WRONG
BUF
%
WRONG
CFM