Can WLS 9234 work on a metal rotating shaft with the rotation rate of up to 150 RPM?

[ylylyl]

I am going to measure sound transimitting through a metal rotating shaft. The plan is to attached an accelerometer (e.g. Endevco 7259B Isotron accelerometer) to the shaft and connect it to a WLS-9234. The acosutic signal (sound) is then picked up and recorded by a laptop.

My questions are: 1) Can WLS 9234 work on a metal rotating shaft with the rotation rate of up to 150 RPM? 2) Can an accelerometer, such as Endevco 7259B Isotron accelerometer, be sensitive enough to record the acoustic (including ultrasonic) signal?

[Margaret F.]

Hello!

Thank you for posting to the NI Forums! I can see no reason why you wouldn't be able to use the WLS-9234 for this application.  I am a little confused though on your use of the accelerometer. Will you be recording vibration data from that? I don't think I'm understanding where your sound data is coming from. Please clarify and I'll be happy to help!

Have a great day!

[ylylyl]

Dear Margaret,

Thank you for answering my questions. We are trying to record sound, not vibration, transmitted through a long rotating shaft. Let me explain what I plan to do. We need to monitor the condition of one end of a long (over 200 meters) rotating mental shaft. However we can not access to this end. For the clarity, let's call it "non-accessible end". Fortunately, sound is generated at the "non-accessible end" when the equipment is working and the sound is related to the condition of this "non-accessible end". We can access to the other end of the rotating shaft, the "accessible end". Therefore the idea is to listen to the sound at the "accessible end" transmitted from the the "non-accessible end" to monitor condition of the "non-accessible end". We need to record the sound as fully as possible in order to get as much information as possible. For this, we plan to record the sound using an acoustic transducer with a frequency range of 2 - 30 KHz.  The only way to record the sound is to attach an acoustic transducer to the rotating shaft. Obviously we cannot use a wired transducer. The ideal solution will be to use a wireless acoustic transducer. However we could not find any wireless acoustic transducer with the broad frequency range. Then I came across the NI's WLS-9234 wireless transmitter. We could connect an acoustic transducer, which is fitted on to the shaft, to the WLS-9234, the sound record by the acoustic transducer is then transmitted to a lap top by the WLS-9234.  We cannot use a microphone to record the sound since a microphone cannot be fitted to the shaft to record the sound directly. The sound signal is too weak near the shaft to be recorded by a microphone. We thought we might be able to pick up the sound by fitting a piezoelectric accelerometer, such as Endevco® model 7259B, directly on the shaft.  Now, my question is, can a piezoelectric accelerometer, such as Endevco® model 7259B pick up sound transmitted though a mental shaft? If not, what is the best type of acoustic transducer should I use? Best regards 

[Margaret F.]

Hello!

First of all as far as whether or not that particular accelerometer will be sensitive enough is not something that I can say. There are many variables here...materials used, noise generated from the spinning motion, etc. 

What sound will you be meauring? Is it sound ffrom the generated wind or sound coming from the rod?

Can you please attacha drawing of your setup so I can be sure I understand?

Thanks!

Have a great day!

[ylylyl]

Hi Margaret,

Thank you for your reply.

Best regards

yunlai