BBFM-Q125K Ultrasonic Gas Flow Measurement Transducer

BBFM-Q125K ultrasonic gas flow transducer with cylindrical body, cable and circular acoustic face

Ultrasonic sensing for gas flow meters

The BBFM-Q125K is a 125 kHz ultrasonic gas flow measurement transducer. It is intended for industrial gas flow meters, gas meters, gas velocity measurement and transit-time gas measurement modules.

The specified reference range is 0.12 to 2 m. Its half-power beam angle is 13.5° ±10% at -3 dB.

Technical specifications

Parameter Specification
Model BBFM-Q125K
Center frequency 125 kHz ±5%
Recommended range 0.12 to 2 m
Minimum impedance 1,100 Ω ±20%
Capacitance 460 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
Half-power beam angle 13.5° ±10% at -3 dB
Dimensions Ø16 × 19
Protection rating IP68
Weight 12 g ±5% with 20 cm cable

Gas measurement applications

  • Industrial gas flow meters
  • Gas meters
  • Gas velocity measurement
  • Transit-time gas measurement modules

Electrical circuit matching

Transmit and receive electronics should be matched to a minimum impedance of 1,100 Ω ±20% and capacitance of 460 pF ±20% at 1 kHz. Peak voltage must remain below 1,200 Vpp.