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MarkL

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Hi Guys I am recently new to Ultrasound testing and I want to get an idea of some optimal freq ranges for various types of detection, 
My Instrument has a variable range from 36khz upto 50 khz which I can adjust, I know I seen a table before giving guidelines for leak testing__ Bearing and gear detection and corona discharge, Just cant seem to recall where I seen it.
Any links or suggestions appreciated.

Mark.

ausconmon

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Reply with quote  #2 
Hey Mark,

Is this along the lines?

Regards.

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MarkL

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Reply with quote  #3 
Spot on Mr...your a star!! though I am concerned about the frequency range for the steam traps as Mine cant go that low.
Walt Strong

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Reply with quote  #4 
Mark,

You should use the frequency range recommended by the instrument manufacturer as a starting point. There are no standards for ultrasound, and every sensor and meter has different frequency response; even from same manufacturer. I recommend experimenting with different settings to see what works be best for your situation. You typically have to make a lot of measurements for a good sample size to make comparisons.

Walt
MarkL

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Reply with quote  #5 
Thanks Walt, I am starting to realize that, My instruments has me slightly confused though, when I reduce the gain to remove competing US noise, the displayed  db reading increases, is this normal?
Walt Strong

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"I reduce the gain to remove competing US noise, the displayed  db reading increases, is this normal?"
Questions like this are best answered by meter customer support.
I would not consider this normal, but there are a lot of US meters that work in different ways. I recall that an old UE-2000 required the addition of the gain and the meter dB value. My SDT-150 does display the same dB value for different ranges (gain) provided the signal is not overloaded. Don't continue to be confused, since it is hard enough to get good data!

Walt
cabrerajm33

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Reply with quote  #7 
Hello please i need your help, is possible to use an ultrasound contact sensor by vibration analyzer csi 2140 by configuring the data acquired in decibels
Walt Strong

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Reply with quote  #8 
The simple answer is yes, based on my use of an SDT 150 meter with a CSI 2120 analyzer. Most ultrasound meters use 1 microvolt as the dB reference and this is not a physical reference unit like g-acceleration or Pa-Pascals pressure. If the UT meter has several gain/attenuator settings, then a different volt per microvolt sensitivity would be needed for each meter setting that is used. The 2140 can be set to dB so the overall value on the analyzer would be close to the overall value on the UT meter. It can get very messy depending upon the UT meter that you have!

Walt,
cabrerajm33

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Reply with quote  #9 
Interesting, do you have any procedure to do it? I would like to trend in db of a low frequency point to increase the acquired signal, the MHM Software has the option of peakvue to a 500Hz filter or the SST but for I want to use several options that help me to take a decision when necessary
Walt Strong

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Reply with quote  #10 
The simple manual way is to setup UT measurement points and use the manual value sensor type. Then add Note Codes to describe the sound from headphone audio. The 2140 would then be used as a data logger for manually entered dB values from UT meter and Note Codes selected for the "sounds like" audio observations.

If your UT meter has an AC voltage signal output, and you have a cable with BNC connector, then you can connect to 2140.

Walt
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