Float switches are simple enough, but what if you need continuous level measurement? The good news is, you can still get a simple float level sensor (we call them level probes) that has a number of advantages.
Advantage 1: Atmosphere
As in, it doesn’t matter. With non-contact sensors, such as ultrasonics, the atmosphere really matters. Anything that disrupts the air column between the sensor and the surface can, in turn, disrupt the sensor.
A continuous float level sensor, or a level probe, doesn’t care about the atmosphere above the liquid surface. Its physics are related to buoyancy.
In other words, heavy dusts and vapors, or anything else that can mess with non-contact sensors, will not affect a level probe. The float will just keep on floating.
Advantage 2: Surface
Floats are made to spec, and we can match specific gravity, or even design it to sit on top of foam if you’d like. We can also make it compatible with any chemicals present.
A few other surface-related factors include reflectivity, turbulence, and the dielectric constant of the media. All can cause problems with non-contact sensors. To get to the point, reflectivity and dielectric permittivity doesn’t matter with floats, and turbulence can be overcome by programmed hysteresis or with a stilling well. (Often, turbulence is a non-factor. Simply waiting for the liquid to settle is usually enough – as most tanks are not under constant agitation.)
Finally, continuous float level sensors are, because of specific gravities, capable of finding the interface between two liquids, such as oil and water. With two floats, a level probe can determine both the interface and top level – showing the level of both liquids.
Advantage 3: Linear Measurement
Because the float is mounted on a stem, or rod, accuracy is improved and variables are reduced. Level probes help control an environment, and can measure a change as little as a few millimeters.
Linear measurement is simpler and highly repeatable. Continuous level floats are a very dependable method for monitoring levels.
The Bottom Line
Above all else, a continuous level float, or a level probe, is very simple. It doesn’t always mean it’s the best solution; many level probes are more expensive to purchase, ship, and install. However, they are often a good answer when a less expensive sensor will not cut it.
If you have questions about if a continuous level float sensor is right for your application, contact our application engineers at 888-525-7300.