O2
| Gas | Oxygen |
| Formula | O2 |
| CAS number | 7782-44-7 |
| Relative density | 1.11  |
| Appearance | Colorless Odorless |
| Hazards O2 V% too low | Impairment until unconsciousness |
| Hazards O2 V% too high | Increased flammability of materials and gases |
The ME1250 Gas Sensor is a remote measuring unit for monitoring oxygen concentration. Lack of oxygen impairs health, up to unconsciousness and danger to life. Too high oxygen content poses a risk of fire and explosion, since materials and gases have a higher flammability with increased oxygen concentration.
The microprocessor-controlled electronics of the sensor, adapted to the specific properties of the measuring cell, enable fast and reliable signal processing. The measured gas con-centration is transmitted to a Gas Control Panel, which can manage a large number of distributed gas sensors.
Thanks to bus communication, only one cable is required, which can be continued from sensor to sensor. The ME 1250 Gas Sensor is also available with an analogue output signal of 4…20 mA. The measured gas concentration can thereby be processed by other PLC (Programmable Logic Controllers).
The optional relay module expands the ME 1250 Gas Sensor internally with 3 relays for direct switching of signal transmitters without the use of a control panel.
Advantages
- Automatic zero point calibration
- Active noise reduction on the measurement signal
- Linear measurement signal depending on the gas concentration
- High response sensitivity with short response time
- Selective and reliable measurement with a stable measurement signal and zero point
- Temperature-compensated measurement signal
- Long service life
Technical Specifications
Versions
| Article code | 12BUS-O2-21 | 1250-O2-21 |
|---|---|---|
| Description | Gas Sensor ME 1250 O2 Oxygen Bus communication | Gas Sensor ME 1250 O2 Oxygen Analogue |
| Output signal | Bus communication with gas control panel | Analogue 4…20 mA Load max. 800 Ω at 24V input |
| Connection | 4-core cable U72M 1x4x0.6 mm Shielded | 3-core cable U72M 1x4x0.6 mm or CY 0.5 mm2 Shielded |
| Topology | Bus, tree or star topology | Star topology |
| Power | < 0.15 W | < 0.8 W |
Signal Processing
with Gas Control Panel
for PLC processing
without Gas Control Panel
Accessories
| Article Code | Description |
| 1250-REL | Relay module for single sensor ME 1250 |
| 1250-AIR-BOX | Ventilation duct add-on box for gas sensor ME 1250 |
| 1250-AIR-FLOW | Fitting hose connection for gas sensor ME 1250 |
| 1250-SUP | Mounting plate round pillars for gas sensor ME 1250 |
| 1250-SCHUTZ | Sun and weather protection for gas sensor ME 1250 |
Consumables
| Article code | Description | Lifespan |
|---|---|---|
| CELL-O2-M100 | Measuring cell for oxygen | up to 3 years |
- The service life of the measuring cell can be shortened by high humidity
Cross sensitivity
| Gas | Concentration | Reading |
|---|---|---|
| Ethene C2H4 | 1’000 ppm | 0 % |
| Carbon Monoxide CO | 2’000 ppm | 0.05 % |
| Hydrogen H2 | 1’000 ppm | 0.1 % |
| Hydrogen Sulfide H2S | 500 ppm | -0.02 % |
| Sulfur Dioxide SO2 | 200 ppm | -0.01 % |
1250-O2-21
