Air Ultrasonic Transducer - Enclosed Type
The Standard Enclosed type transducers, are designed to be hermetically sealed and can be used for outdoor installations, as well as dusty indoor atmospheres.
The transducers consist of a metal housing with integral metal diaphragm. They operate at resonance on the first harmonic overtone. The backs of these transducers are completely sealed with resin, protecting them from exposure to the environment.
Although it is constructed to be watertight, it is not recommended for use under water.

400ET250 Finite Element Analysis
Frequency: 40.52KHz
Click for motion animation

Model Number Description Center Frequency
(KHz)
Sensitivity or SPL
(min.)
Bandwidth
(-6dB)(KHz)
Dimensions
(mm)>
250ET250
250ER250
Transmitter 25.0¡Ó1.0 113dB 1.0 25.0£p x 12.0
Receiver -63dB
328ET250
328ER250
Transmitter 32.8¡Ó1.0 113dB 1.0 25.0£p x 14.2
Receiver -67dB
400ET080
400ER080
Transmitter 40.0¡Ó2.0 100dB 1.5 8.4£p x 4.6
Receiver -80dB 2.0
400ET180
400ER180
Transmitter 40.0¡Ó1.0 115dB 1.5 18.0£p x 12.0
Receiver -70dB
400ET250
400ER250
Transmitter 115dB 1.0 25.0£p x 12.0
Receiver -70dB

SPL: 0dB = 0.0002ubar, measured upon 10Vrms sine wave at 30 cm distance;
Sensitivity: 0dB re 1V/ubar, receiver in parallel with a 3.9K Ohm resistor