Hach Ultra ORBISPHERE 510, Operator'S Manual

Page: 57 / 144

Orbisphere 510/511/512 Analyzers - Measurement Menu 51 of 138
Operator Manual
ORBISPHERE
4.2.6 Interferences Configuration
These options are available to take into account the influence of some components or
gases in the sample during measurement. All available interference corrections are
disabled by default.
The following interference corrections are available:
• For oxygen measurements - CO
2
, H
2
S, Chlorine, Salt, H
2
• For hydrogen measurements - Temperature, H
2
O, He, O
2
• For nitrogen measurements - Temperature, H
2
O, O
2
, H
2
Note:
If you believe you need to enable any of the above, it is advisable to contact a Hach
Ultra Service Representative first.
4.2.6.1 Interferences in Oxygen Measurement
In some applications, like in the beverage industry, there can be high concentrations of
carbon dioxide in the sample. Hach Ultra recommends using the CO
2
interference option
if a carbon dioxide concentration of over 1% in gas phase, or 15 ppm in dissolved phase
is present.
In the petroleum industry, the detection of oxygen is sometimes hampered by significant
concentrations of hydrogen sulfide in the sample. Hach Ultra recommends using the H
2
S
interference option if the hydrogen sulfide concentration exceeds 0.15% in gas phase, or
5 ppm in dissolved phase.
To operate the oxygen sensor in these conditions
requires using a different sensor and electrolyte.
When using this mode your system
will experience sensitivity loss of about 50 times higher than the minimum sensitivity for
the membrane.
The instrument can also compensate for the presence of high hydrogen levels in the
sample.
CO2 or H2S: Select CO
2
, H
2
S or All disabled.
Chlorinity/Salinity: Select Chlorinity, Salt or All
disabled. For chlorinity or salt, it is required to enter
the actual concentration in the sample.
H2: Select H
2
enabled or disabled. It is required to
enter the interfering gas pressure, which is the partial
pressure of H
2
in the sample.
When enabled, the H
2
interference must be calibrated.
See “Interference Calibration (EC sensor)” on page 63 . A
warning pop-up window is displayed to remind the user of
this action.