140 kHz transducer for compact gas measurement paths
The BBFM-Q140K is an ultrasonic transducer for industrial gas flow meters, gas meters and gas velocity measurement. It can also be integrated into transit-time gas measurement modules. Its documented reference range is 0.12 to 1 m.
The acoustic specification gives an 18.2° ±10% half-power angle at -3 dB. The transducer operates from -40 to +80°C, supports pressure up to 3 kgf or 0.3 MPa, and has an IP68 protection rating.
Verified acoustic and electrical data
| Parameter | Specification |
|---|---|
| Model | BBFM-Q140K |
| Center frequency | 140 kHz ±5% |
| Recommended range | 0.12 to 1 m |
| Minimum impedance | 1,200 Ω ±20% |
| Capacitance | 250 pF ±20% at 1 kHz |
| Operating voltage | Peak voltage <1,200 Vpp |
| Operating temperature | -40 to +80°C |
| Pressure rating | ≤3 kgf or 0.3 MPa |
| Beamwidth | 18.2° ±10% half-power angle at -3 dB |
| Mounting | Refer to the dimensional drawing |
| Protection rating | IP68 |
| Weight | 8 g ±5% with a 38 cm cable |
Planning a short gas-flow acoustic path
The 0.12 to 1 m reference range and 18.2° ±10% half-power angle should be used together when positioning the transducers in the meter chamber. Final path length, target geometry, mounting space and interface dimensions must be checked for the intended instrument.
The electronics need to accommodate a minimum impedance of 1,200 Ω ±20%, a capacitance of 250 pF ±20% at 1 kHz and peak voltage below 1,200 Vpp. The listed weight of 8 g ±5% corresponds to the configuration with a 38 cm cable.
Details to establish before integration
- Gas medium and temperature range
- Required measuring distance or acoustic path
- Meter chamber and target geometry
- Mounting space and interface dimensions
- Operating pressure and protection requirements
- Drive/receive electronics, cable routing and connection method