Ultrasound wattmeter

An ultrasound wattmeter. Netech UPM 2000 Radiometer.


An Ultrasound Watt-meter (Radiometer) are testing devices used in performing output measurement tests and performance verification on ultrasound equipment. Mostly, these multifaceted devices performs primary measurements of total-pulsed or continuous-average power (in watts) measurements. These devices are tested using either distilled and/or degassed water (never use regular tap water for performing measurement checks--will result in inaccurate readings). Lastly, technicians can store, print data, or possibly transfer it to an automated computerized maintenance management system for archival.


1. Use an ultrasonic cleaner to evaporate the bubbles from the distilled water for a minimum of 30 minutes. Alternative method is to boil distilled water for a minimum of 30 minutes.

2. Cool to a luke warm temperature of 95 degree Ferenheit before using

3. Using a glass/plastic container, fill transducer well to 30 ml level. Carefully replace the container's cap but take care not to trap any excess air under it.

4. Degassed water exposed to the air will soon begin absorbing the atmospheric gasses that were evacuated using the previously mentioned procedure. Therfore, for best results, make your measurements within a 10 minute time period. If the UMR-3D readings start to "drift" downward, the transducer well should be refilled with fresh degassed water. If an extended series of tests are to be made, replace the degassed water every 10 to 15 minutes. To ensure that air bubbles do not reside on the face of the transducer, carefully run a string across the face of the transducer as it rests in the degassed water.

Important: Many types of water, including sterile or bottled water, are typically found in a hospital. These types of water do not come in the degassed form and should not be used as the coupling medium without first following the above degassing procedure.


  • UW 5 - Fluke
  • UMR-3D
  • UW-3 - Bio-Tek
  • UPM 2000 - Netech



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