If you’re interested in building a tank level monitoring solution, you’ve probably already investigated your options–from sensors and products to packaged end-to-end solutions. Before we delve into some of those offerings, let’s take a look at some of the things you’ll need to consider about your use case: ‍

Network Infrastructure 

LoRa 

Shorthand for Long Range, uses license-free sub-gigahertz radio frequency bands to transmit small packets of data over a larger geographic area. To deploy a network, you’ll need to install LoRa gateways (e.g. MultiTech, MachineQ, Tektelic) near your sensors and rely on them to backhaul your data into the cloud, oftentimes using cellular data or a physical ethernet connection. ‍

Cellular 

Use existing cellular network infrastructure (cell towers) to backhaul data into the cloud. No gateways required, however regions and locations with poor cellular connectivity / coverage, such as large buildings and underground facilities. ‍

Sensors

• Ultrasonic - Uses the reflection of high frequency sound waves to determine how far away an object is. Works with centimeter level resolution on targets that are ideally large, smooth and flat. Functional at ranges of up to 20m. 
  

• Lasers - Uses the reflection of focused pulse of light to determine how far away an object is. Works with millimeter level resolution on targets that are poorly suited for ultrasonic sensors (e.g. narrow pipe). Functional at ranges of up to 200m. 
  

• Hydrostatic Devices - There are many more traditional solutions using a variety of techniques, from simple water displacement to changes in capacitance or clever use of magnets that make up the bulk of sensors currently on the market. While they do provide accurate and reliable data, they don’t always come packaged as a connected solution. As a result, they may be more difficult to integrate to build a connected IoT solution. ‍

‍Products‍

Now that we’ve covered connectivity and sensors, let’s talk about products. Keep in mind, this is just a shortlist of some products available on the market, and is not intended to be a comprehensive purchasing guide. ‍

ELT-2-HP + Maxbotix Ultrasound Sensor‍

At a price-tag of €255 Euros or $280 USD, this is an American sensor product integrated with a Swedish LoRa adaptor. As the name suggests, it is a LoRa-based sensor that transmits distance data based on the ultrasonic sensor embedded at the center of the cone piece. 

CleanFLEX Ultrasonic Fill-level Sensor

Similar to the previous device, this product operates using an ultrasonic sensor and can transmit its data over LoRa as well. It is also capable of transmitting data over 2G/3G networks, and NB-IoT networks as well, which makes it an adaptable option across a wide variety of use cases. 

KST 3320 Distance Sensor 

This device can measure distances of up to 2m with a 1cm level of resolution. It measures distance using pulses of light and communicates that data over Bluetooth and LoRa.

‍Pricing

As you may have noticed, while the technology has already existed in separate pieces for many years, productized versions of these devices are relatively uncommon, undeveloped, and much more difficult to find. Pricing information is not always easy to find, or publicly available, and often requires navigating through sales and marketing channels. 

Hopefully, this overview was helpful in guiding you towards building a tank level monitoring solution of your own. As always, feel free to reach out with any questions.