Sensor needed

[dbday]

Hi,
What I need to do is to measure a dynamic pressure which oscillates around an average pressure.

My average pressure is 90 BarG whilst the oscillations are less than 1% (PTP) about this average.
My problem is that the sensors I have are 0-100 BarG, with an accuracy of +/-0.15% of full scale (output is 0-10V FS)
The sensor covers the range, but the accuracy does not meet my needs and I don't think it is practical to buy anything with a better accuracy (if such a sensor exists).

Has anyone ever heard of a pressure sensor that gives its full scale output over a limited elevated range, say in my case 0-10V over 80 to 100 BarG, or is such athing wishfull thinking.

Sorry if this is the wrong place to put this post, but I wasn't sure on the best forum.
Thanks

 

[GregLocock]

I'd try the one you have. +/-.15% doesn't sound very good if you are trying to measure to 1% but I wouldn't mind betting that the .15% error is more of a drift over the whole scale than a local effect.

That is, it may measure 90 true as 90.1, but I bet if the real pressure changes to 91 true the reading would be 91.1

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?

 

[Strong]

Take a look at piezoelectric dynamic pressure sensors that do not measure static pressure.

http://www.pcb.com/products/browse_productlist.asp?RequestType=Filter&CategoryType=Measurement

Type&CategoryId=35&app=1005&tech=&config=&SearchCriteriaWithin=

I have used these products on blowers and pumps.

Walt

 

[Compositepro]

Use a differential pressure sensor with a restrictive orifice in one sensor line so that line stays at the average pressure. The other line will respond to the fluctuations from average.

 

[Strong]

Making an accurate dynamic pressure measurement is more difficult than static pressure. Restrictive orifices and long lines will grossly change frequency response of dynamic pressure. Besides finding a suitable sensor, one needs a little study of fluid/pulsation dynamics.

Walt

 

[dbday]

Thanks Compositpro, that sounds like a "why didn't I think of that" idea.
Cheers