Ultrasonic flometer accuacy & prices

[aladili]

Hi,
I want to ask if there is some one knows about the capability of using ultrasonic flowmeter for determining water treatment plant production instead of electromagnatic one. what is the accuracy ( error percentage )of it what about the prices comparisons?

 

[bimr]

The manufacturer of the device is the best source of information on accuracy. The accuracy will depend on the application, the piping arrangement, the range of flow that you are measuring, the percentage of scale where you are operating, etc.

However, as a general statement, the magmeter is a little more accurate, slightly more expensive, and slightly more reliable than an ultrasonic meter.

 

[aladili]

is it correct that the reading error of most ultra sonic flowmeters reachs 40%!

 

[bimr]

No, properly installed, an ultrasonic flow meter is typically accurate to 1-5% of full scale.

http://www.omega.com/prodinfo/ultrasonicflowmeters.html

The magmeter is typically accurate to .5% of full scale.

 

[aladili]

THANKS alot bimr you are very helpfull.

 

[bimr]

Here is another link:

http://www.ianrpubs.unl.edu/epublic/live/g1426/build/g1426.pdf

 

[gsec]

Be careful, accuracy of different manufactures products vary greatly. Despite their own documentation. Ask for a demo on a known constant flowing pipe if possible.
Also placement is important as well as specifics on pipe dimensions, specific gravity of fluid measured, pipe material etc.

 

[mxmaciek]

1. Application of the ultrasonic vs magnetic is the option for the low conductivity water;
2. Accuracy varies from the piping, scale of the flow, water turbulence in the pipe.
3. Always (at least for some manufacturers, i.e. Endress + Hauser) you can verify the real flow by use of the external flowmeter and adjust the constant value, thus ensuring the proper metering;
4. You can consider the use of old, good orifice, and for some purposes it will be the best choice (not for all of course)