Hach-Lange ORBISPHERE 6110 User Manual - Manual (Page 20)

18
Specifications
2.4 Instrument switches and buttons
2.5 Operation overview
1. Piercing
The reference volume is filled with the purge gas and the whole of the gas sampling path is fully
purged. The purge stops when the rubber seal of the piercing device contacts the top of the
package. Once the package is pierced, a pump injects an antifoam solution into the headspace.
2. Oxygen in headspace and CO
2
The pressure is measured, then the regulating valve is opened and the gas contained in the
headspace flows over the O
2
and the CO
2
sensors at a given rate. The quantity of O
2
in the
headspace is obtained by integrating the volumes of O
2
leaving the package per unit of time.
The temperature is measured and combined with the pressure to calculate the CO
2
P/T value.
3. Liquid analysis (O
2
)
The gas flow is stopped and the ultrasonic sonotrode is activated. The regulating valve is then
opened and the gas escaping the liquid mixes with the gas of the headspace. The O
2
signal is
an exponential function to which coefficients can be included and the total O
2
contained in the
bottle is calculated by integrating this function.
Note: For faster measurements, the liquid analysis step can be skipped and the O
2
value calculated from
the headspace by setting specific parameters for the package (see Package parameters on page 35 for
additional details).
4. Headspace volume
At the end of the run, the gas flow is stopped and the valve is opened. The gas of the reference
volume expands in the headspace and the pressure reaches a new value. The headspace
volume is calculated with the ideal gas law principle.
5. End of measurement
The piercing head assembly is lifted out of the package. A short burst of gas purges the gas
sampling path to flush out any residual liquid or foam. The system returns to the standby mode
where the sensors are kept under a slight purge gas flow.
The mains power switch is located at the rear left of the instrument (No. 2 in Figure 3 on
page 16 ). To switch the instrument on and off, press the rocker switch to the
required position: “O” for Off and “I” for On.
The measurement button is located at the front right of the instrument (No. 5 in Figure 2
on page 15 ). Press this button to start a package measurement.