Model GLI-9143 Portable D.O. Meter
6
Rev. 0-401
For an accurate measurement, allow suffi-
cient time for thermal equilibrium between the
probe and the measurement sample (a few
minutes if the temperature difference is sev-
eral degrees).
ppm READINGS
The ppm readings make it possible to read
the concentration of the dissolved oxygen di-
rectly.
If the sample contains significant salinity or if
the measurement is taken at a higher altitude
than sea level, the readout values must be
corrected (by taking into account the lower
degree of oxygen solubility in such conditions
-- see below).
Set the altitude and/or the salinity before cali-
bration and taking ppm measurements. The
meter will automatically compensate for these
factors.
% O
2
SATURATION READINGS
The % O
2
saturation reading provides the
rate of oxygen saturation with reference to
100.0% at sea level.
TEMPERATURE READINGS
The lower part of the dis-
play will show the
measured temperature in
degrees Celsius.
Allow the probe to reach thermal equilibrium
with the sample before taking any measure-
ment. The greater the difference between the
ambient temperature and the temperature of
the sample, the longer it will take the probe to
equilibrate to the sample.
ALTITUDE COMPENSATION
Press FACTOR and “F1”
will be displayed. Use the
UP and the DOWN keys to
set the altitude from 0-4000
m (0-13,123 ft.), in steps of
100 m (328 ft.).
SALINITY COMPENSATION
Press FACTOR twice and
“F2” will be displayed.
Press UP and DOWN to
set the salinity between 0
and 80 g/l. Press FACTOR
again to display the tem-
perature.
PROBE AND MEMBRANE MAINTENANCE
The dissolved oxygen probe body is made of
reinforced polypropylene for maximum dura-
bility. A built-in thermistor measures the
temperature of the sample. It is recom-
mended that the protective cap always be
kept on the probe when the probe is not in
use.
To replace the membrane cap
or refill it with
electrolyte, proceed as follows:
1.
Remove the protective
cap by gently twisting
and pulling it off the
probe (see Figure 1).
FIGURE 1