Level Sensor outputs

CAAJ

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C

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Dec 2014

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Fairhaven, Ma

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• Nov 6, 2015

• #1

Hello All,

Does anyone know if a 4-20ma signal would provide enough resolution for a level sensor. I want to make sure that the level recorded by our compactlogix controller is accurate.

We would like to utilize an ultrasonic level sensor.

Any feedback would be useful!

 

iggy

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May 2007

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FLORIDA

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• Nov 6, 2015

• #2

Not sure what, where, and how much you are measuring.
I use radar units with 4-20 measuring dry product and they work great.

 

rdrast

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Apr 2003

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South Carolina Lowcountry

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• Nov 6, 2015

• #3

Without any requirements for your "Resolution", or the accuracy of the sensor, I would say yes.

 

CAAJ

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C

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• Nov 6, 2015

• #4

Sorry about that. We're looking to measure high and low viscosity fluids in a rectangular storage tank. The unit is only 4.5' tall. And I would say we would like to shoot for about <2% accuracy.

 

Last edited: Nov 6, 2015

RoTaTech

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May 2003

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Cobourg, ON, Canada

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• Nov 6, 2015

• #5

Typical A-D cards

use 12 bit resolution. That's 4096 counts, much better than 2%.

If you ensure that your sensor range is reasonably close to the range of your tank levels, you will get sufficient resolution.
e.g. If you are looking to measure a 5' range, shop for a sensor with 6'-10' range, so your 4-20mA output will be maximized over your range.

 

CAAJ

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• Nov 6, 2015

• #6

Thank you all!