BBDM-21KR25M Long-Range Air Ultrasonic Distance Transducer

BBDM-21KR25M air ultrasonic distance transducer with white PTFE body and black upper assembly

Medium-to-long-range sensing with a PTFE housing

The BBDM-21KR25M is an air-coupled ultrasonic transducer with a 21 kHz center frequency and a reference range of 1.0 to 25 m. It can be evaluated for large-tank level monitoring, industrial distance measurement, collision avoidance, area monitoring and long-range target detection.

The transducer body is specified as PTFE and the protection rating is IP68. The housing designation alone does not establish compatibility with every chemical environment.

Technical specifications

Parameter Specification
Model BBDM-21KR25M
Center frequency 21 kHz +/-5%
Recommended range 1.0-25 m
Minimum impedance 1,100 ohm +/-20%
Capacitance 11,000 pF +/-20% at 1 kHz
Operating voltage Peak voltage below 1,500 Vpp
Operating temperature -40 to +80 degrees C
Pressure rating Up to 3 kgf or 0.3 MPa
Beam characteristic -3 dB half-power angle: 13 degrees +/-10%
Housing material PTFE
Protection rating IP68
Weight 1,480 g +/-5% with 10 m +/-0.3 m cable

Tank geometry and echo clearance

The 13-degree half-power angle describes the acoustic field within the vessel. Fill pipes, ladders, braces and sloped surfaces can return echoes before the intended level surface. The lower end of the reference range is 1 m.