At-line digital CO2 and O2 meter for beer and carbonated beverages, type OXI-GMD
The digital CO2 and O2 meter type OXI-GMD (CO2 / O2 GEHALTEMETER) is used to determine the content of dissolved carbon dioxide and oxygen in beer, carbonated beverages, soft drinks, and sparkling wines. Measurements can be carried out directly during the production process on production lines, in cylindroconical and pressure tanks, as well as in kegs.
The instrument is also suitable for laboratory use for determining oxygen content in beverages packaged in bottles and cans. For these measurements, in addition to the O2 meter itself, the ICAS sampler must be used. The sampler ensures safe sampling from bottles or cans without the risk of contamination by oxygen from the ambient air.
Measurement Principle:
The instrument for determining CO2 content operates on the principle of Henry’s law. The CO₂ content is determined by measuring the temperature and the partial pressure of CO₂ in equilibrium after mechanical shaking of the beverage. A piston allows carbon dioxide to be released very quickly, eliminating the need to shake the device.
For O2 measurement, an optical probe (electrolyte-free) is used, enabling accurate determination of dissolved oxygen in beverages. The O2 measurement is not affected by other dissolved gases and can therefore be used for reliable monitoring of oxygen content in beverages.
Working Procedure:
The instrument’s filling valve is connected, using the supplied tubing, to a sampling valve on the pipeline or to a tank in operation. The CO2 measuring chamber is then filled with a beverage sample, while the beverage simultaneously flows through the O2 meter measuring chamber.
The flow of the beverage through both the CO2 measuring chamber and the O2 meter measuring chamber can be finely and independently regulated using the drain valves, so that foam formation is prevented during filling. After selecting O2 measurement, the measurement is started by pressing the Enter key. The measured oxygen value should be read only after it has stabilized.
Once the measuring chamber is filled, the outlet valve is closed first, followed by the inlet valve. Then the pressure in the measuring chamber is zeroed by brief opening and closing of the outlet valve. Dissolved CO₂ is released by repeatedly pulling and pressing a piston in the upper part of the measuring chamber, increasing the pressure inside the chamber.
After this preparation and selecting CO2 measurement, the measurement is started by pressing the Enter key. The instrument automatically measures pressure and temperature, calculates the CO2 content, and displays the resulting values in g/L and volume percent on the display.
Technical description of the O2 meter:
- Highly sensitive optical O2 sensor providing excellent measurement repeatability.
- The instrument is supplied with two types of O2 sensors. The standard range is up to 10,000 ppb. Optionally, the O2 meter can be equipped with a sensor with a range up to 2,000 ppb, which offers higher accuracy and faster response time.
- No influence from other dissolved gases.
- O2 measurement is independent of the flow rate of the measured medium.
- User-friendly operation.
- Data Logger function: enables continuous monitoring of O2 content from a pipeline or tank.
- Measured values can be displayed on a mobile phone equipped with a Bluetooth interface and the ArcAir software installed. The ArcAir software is available for free download from Google Play or the App Store.
- Option for independent user calibration of the O2 sensor using a Bluetooth-enabled mobile phone with the ArcAir software installed.
- Regular calibration of the O2 sensor zero point (0 ppb) is required at least once every six months.
Technical data:
| Parameter | Values for the O2 meter sensor with a range of 0 to 10,000 ppb | Values for the O2 meter sensor with a range of 0 to 2,000 ppb |
| Oxygen measuring range | 0 až 10 000 ppb | 0 až 2 000 ppb |
| O2 Accuracy | 7 ppb | 1 ppb |
| Units O2 | ppb, ppm | ppb, ppm |
| Max.temperature | 700C | 700C |
| Max. operating pressure | 6 bar | 6 bar |
| CO2 measuring range | 2 to 9,99 g/l (1 to 5,15 vol) | 2 to 9,99 g/l (1 to 5,15 vol) |
| CO2 Accuracy | 0,1 g/l or 0,05 vol | 0,1 g/l or 0,05 vol |
| Temperature measuring range | -3 to +30 °C | -3 to +30 °C |
| Pressure measuring range | 0 to 600 kPa (0 to 6 bar) | 0 to 600 kPa (0 to 6 bar) |
| Temperature measurement accuracy | 0,1 °C | 0,1 °C |
| Pressure measurement accuracy | 0,5 % | 0,5 % |
| Instrument dimensions | 280 x 180 x 350 mm | 280 x 180 x 350 mm |
| Weight | 3 kg | 3 kg |
| Protection rating (with connector cover screwed on) | IP 54 | IP 54 |
| Interface | Bluetooth | Bluetooth |
| Memory | 200 measured values | 200 measured values |
| Power supply | AA 1,2V NiNH rechargeable batteries – 6 pcs | AA 1,2V NiNH rechargeable batteries – 6 pcs |
| Charging | AC/DC adapter 24V/200mA | AC/DC adapter 24V/200mA |
| Display | Digital, 4×20 characters | Digital, 4×20 characters |
Scope of Delivery:
Digital CO2 and O2 meter type OXI-GMD, filling hose made of polyurethane, silicone drain hose, charger, operating manual.
Accessories (optional):
- Sampling head for taking beverage samples from a keg
- Sampler for taking samples from packaging (bottles, cans), type ICAS
Advantages & Benefits:
- High accuracy and calibration capability: ideal for laboratories with an established ISO 9001/9002 quality system.
- Easy O2 sensor calibration using a Bluetooth-enabled mobile phone.
- No influence from other dissolved gases on O2
- O₂ measurement is independent of the flow rate of the measured medium.
- The O2 measuring chamber is equipped with a transparent window, allowing visual inspection to ensure that no CO2 bubbles are forming on the oxygen sensor, which could affect measurement accuracy.
- Release of bound CO2 from the beverage is ensured by a pressure shock generated by pressing the pump piston, resulting in faster and more reproducible measurement results.
- In addition to measuring CO2 and O2, the instrument also allows independent measurement of temperature and pressure.
- Many years of experience: we have been manufacturing CO2 and O2 content meters for more than 25 years and have produced thousands of units during that time. Our CO2 and O2 content meters are used by both large companies and small producers.
- Excellent price-to-performance ratio.
Downloads
Product sheets, catalogues and technical documentation.
Frequently asked questions
What are the differences between the O2 sensors?
The O2 sensor with a measurement range of up to 10,000 ppb is universal and covers all common measurement needs in production environments. This versatility, however, is offset by lower measurement accuracy.
The O2 sensor with a measurement range limited to 2,000 ppb offers significantly higher accuracy. It is therefore intended primarily for monitoring oxygen content in the final product, where very low O2 concentrations are present. However, the sensor with a measurement range of up to 2,000 ppb is more expensive than the sensor with a range of up to 10,000 ppb.
How often does the O2 meter need to be calibrated?
The O2 meter must be calibrated at least once every six months.
How often do the pressure and temperature sensors need to be calibrated?
The pressure and temperature sensors should be calibrated every two years.
What can affect the accuracy of oxygen measurement?
Measurement accuracy can be negatively affected, in particular, by using inappropriate tubing, through which oxygen may diffuse into the beverage. For example, silicone tubing is unsuitable because it is permeable to oxygen. In contrast, tubing made of polyurethane polyether is suitable, as it does not allow oxygen to pass through.
Another potential source of error is leakage between the inlet tubing and fittings, through which oxygen can enter the measured medium.
Is it possible to measure CO2 in bottles and cans with the OXI-GMD?
No, this instrument is not suitable for measuring CO2 in bottles or cans. The reason is the large volume of the CO2 measuring chamber, which cannot be sufficiently filled with the beverage from a bottle or can.
Is it possible to measure O2 in bottles and cans with the OXI-GMD?
Yes, this instrument is suitable for measuring O2 in bottles and cans. However, for these measurements, it is necessary to use the ICAS sampler, which allows a beverage sample to be taken from a bottle or can without contamination from oxygen in the surrounding air.