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Distance meters

1.3K views 8 replies 9 participants last post by  mitch65  
#1 ·
I was wondering if anyone out there knows of any kind of distance meter that would work for clear liquids. (I E coconut oil). It seems a laser reads right through the oil and I'm not sure if a sonar unit would work either. I have a stainless steal tank that we would like to know how full or empty it is as the product is being used. Thanks for any thoughts.
 
#7 ·
Laser probably isn't working because the clear liquid isn't reflecting enough back to register on the sensor. Utrasonic would work because the reflection is physical and the sensor will detect the echo off the surface.

There are lots of other options too, like pressure, GWR, capacitance... although ultrasonic is probably your best bet due to being non-contact, which is preferable in the food industry.

What about a flow monitor on the input and output pipes? And/or a simple float type transducer?
Although monitoring the flow in and out works in a perfect world, it's not a direct measurement and prone to developing an error/offset. Even then you'd need two Coriolis meters or something otherwise temperature/pressure corrected and it would end up being a lot more expensive. Floats only work for point detection, which is fine for simple fill/drain controls but not actual monitoring.
 
#9 ·
Differential pressure works well for level monitoring as long as you have the fittings on the vessel you are measuring, ultrasonic will work as well as long as the surface is calm and there is no foaming (may need stilling well) and has the benefit of having no contact with the fluid. Capacitance probe may work but needs to sit in the fluid.
Float columns with magnetic switches work but the float is in the fluid.