Well you’re not alone. This liquid level sensor is very easy to install and set-up, is inexpensive, rugged, and widely applicable. So what is it? Before I give you the answer, let’s discuss what it is not.
(Disclaimer: In the world of sensor selection, application is always king, and will ultimately determine which sensor is best.)
Ultrasonic sensors are great, but they require careful mounting, sometimes complex set up, and are affected by a number of variables that can hinder performance. While ultrasonic sensors are a great solution for those who need non-contact level measurement on a budget, we’ll never recommend one in an environment where it won’t perform well.
Continuous level floats, or level probes, are very accurate, but they can be rather expensive. For those who need the accuracy, and especially the hazardous location ratings that our level probes come with, we recommend these high performing sensors.
However, they cost a bit more. The price tag is higher, and everything from shipping to installation costs more because of the size and weight of the sensors. Even a relatively small one is bigger than, say, and ultrasonic.
Radar is popular in difficult applications for good reason, but they are very expensive – even more so than our level probes. If you need one, we suggest you find a good one, but in most cases you can find acceptable performance in a much less expensive sensor.
Radar sensors are also complex. Set up requires a bit of expertise – which means you’ll have to put the best person on the job when he/she might be needed elsewhere. Therefore, it’s best to look elsewhere unless you run out of options.
Are you finally ready for the answer? I’m dying to tell you about it! Okay, here goes.
Pressure sensors are the simplest, most versatile tech for continuous level measurement. They can be built to handle extremely harsh conditions (I know ours are!), and various materials are available for chemical compatibility.
There are really two main options here: measurement in units of level (such as gallons, inches of water, volume, etc) or units of pressure (such as psi, bar, etc).
If you want units of level, then you should look for a submersible pressure transducer such as our PT-500. Don’t be fooled by the name – it doesn’t have to be submerged. It can certainly tie into a process connection at the bottom of the tank. You can mount it however you need to, and still get the units of measure you want.
If you want units of pressure, then you’re looking at traditional pressure transducers. We recommend our PT-400 because it’s very rugged and versatile. These sensors cannot be submerged in liquid (to be honest, our sealed PT-400 is tested under water and it works fine). They should be mounted on the exterior of your tank in a process connection located at the bottom.
Do it right and you’ll have an inexpensive level measurement tool that is accurate up to 0.1% full scale, and requires very little set up. To learn more, you can check out our above mentioned pressure sensors or contact us for help.