Previous in Forum: PID Tuning   Next in Forum: User Manual for Wheatstone Bridge
Close
Close
Close
4 comments
Anonymous Poster

Eddy Current Vibration Transducers ?

08/15/2009 9:42 AM

Could someone please tell me about bently nevada vibration monitoring system.

I have read about it that in the output of Proximitor DC portion is directly proportional to the gap and AC portion is directly proportional to the Radial Viabration.

So, my question here is, What kind of output does the proximitor give? AC or DC.

I connected proximitor, extension cable and Probe ( Complete Setup), with TK-3 ,

and run the Tk-3, the output was just like normal DC, (as according to gap). But when I turned Multimeter to AC, I noticed frequency in the output , it was about 178 khz ( or hz, I forgot exact one). Someone please tell me the reason of this.

Has anyone experience of connecting oscilloscope on the output of proximitor.

I wonder how would the shape of the output be in oscilloscope.

Thanks in Advance.

Reply
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
2
Commentator

Join Date: Dec 2007
Location: texas
Posts: 92
Good Answers: 8
#1

Re: Eddy Current Vibration Transducers ?

08/15/2009 7:47 PM

Hi, the output of the proximitor when it's looking at vibration is peak to peak ac voltage if you check the output of the proximitor with your meter on ac you will get rms ac voltage.

The dc voltage will only give the average out put which is useless when looking at vibration.

For example if you have 5 mils of vibration at 200 Mv per mil(you will have to shoot the curb to compare voltage to gap to find this value if you want to be precise) the out put from the proximitor will be 1 volt so you divide that value by 2 because you are going to read rms voltage (half of the wave) then multiply by the constant 0.707 which will equal to .3535 ac rms voltage.

We never use an oscilloscope to check our proximitors but if you connect one to a proximitor it is going to show an ac wave and then you can figure the peak to peak value. Hope this helps..... wrench puller "the nuts and bolts man"

__________________
"The older I get -The better I was"
Reply Good Answer (Score 2)
Anonymous Poster
#2
In reply to #1

Re: Eddy Current Vibration Transducers ?

08/17/2009 11:09 AM

Hey! Wrench puller, Thanks for your satisfactory reply.

So, you mean that the gap voltage only shows the distance between the probe and the shaft, and not the vibration.

Here is another related question:

What kind of modulation is used in proximitor? FM or AM and how is it behaviour on change of the gap?

I wonder howcome a "nut and bolt man" knows this much about vibration .

Thanks for you help.

Reply Score 1 for Good Answer
Guru

Join Date: Aug 2007
Location: Indiana, USA
Posts: 579
Good Answers: 61
#3
In reply to #1

Re: Eddy Current Vibration Transducers ?

08/18/2009 12:18 PM

Good Answer, wrenchpuller! I've often found that a "hands on" nuts & bolts guy is worth several engineers who have never had to actually fix anything.

__________________
Experience: The knowledge you gain just AFTER you needed it.
Reply
Commentator

Join Date: Dec 2007
Location: texas
Posts: 92
Good Answers: 8
#4
In reply to #3

Re: Eddy Current Vibration Transducers ?

08/19/2009 2:17 AM

Hi, Thanks for the compliments.

The proximitors are AM modulators. amplitude and voltage work together.

" you are nothing but a wrench puller" or "you are just the nuts and bolts man"

those are a few things that a have being told by some of the engineers I work with, when we have disagreements or when I make suggestions, They are good men and women and I respect them for what they are, but for some reason they always consult with the "wrenchpuller" and the "nuts and bolts man" when they feel lost or unsure of how things work in the real world. Thanks guys

__________________
"The older I get -The better I was"
Reply Score 1 for Good Answer
Reply to Forum Thread 4 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Copy to Clipboard

Users who posted comments:

Anonymous Poster (1); pwr2thepeople (1); wrenchpuller (2)

Previous in Forum: PID Tuning   Next in Forum: User Manual for Wheatstone Bridge

Advertisement