signal conditioning .

[Fayasoft]

I am measuring Torque signal (up to 80,000ft-lb) using Torque Trak Revolution System from Binsfeld  Engineering.

It gives 12­+8 mA or 4-20mA output. On the other hand I used Fieldpoint AI-100 from National instrument to measure mA.

Other parameters (RPM, Direction , Temperature) are OK in the program except Torque which is fluctuating and not giving even close values , lets say If the applied torque is 5000ft-lb , then I am getting reading anywhere between 4000 and 6500 .

What should I do in my Program , I heard we can use signal conditioner ? what is that? Or any thing else I can do in the Program…..

Any help will be highly appreciated ……

Many thanks in advance,..

Fayasoft.

[Brian_K.]

Hi Fayasoft,

Are you translating a voltage into a torque?  If so, can you confirm with a multimeter or some other device than the FieldPoint that the correct voltage corresponds to the torque?  Then make sure that the AI-100 is measuring the correct voltage.  This way you can isolate the torque transducer, and the FieldPoint.  Divide and conquer 🙂

[Fayasoft]

Hello Brian,

Thanks for reply.

The Strain gage at rotating shaft is generating 4-20mA signal against torque. I am reading this mA through AI-100 analog input module.

when I open MAX I can't see the mA fluctuation ( because of the high frequency I beleive) , but in my LabView Front Screen there is a lot of fluctuation. I did not check but even if I am going to put my multimeter I think I will not see the mA fluctuation.

Is there any thing I can do in the LabVIEW so I can see the average or filtered or signal conditioning will make some difference.

What do you suggest?

Fayasoft

[Brian_K.]

Hi Fayasoft,

I assume by fluctuations you mean "noise".  If you have a noisy signal, you can smooth your signal with lots of different methods.  The easiest is by taking a running average.  If you look at he running average example in the Example Finder that would give you a way to solve the issue in software.  If you need to do it in hardware, you may look into using a low pass filter.

Another idea is to use the FieldPoint Express VI in conjunction with the with the filter or statistics express VI.