When it comes to picking a level sensor for remote tank monitoring, you have an important choice to make: do you get a level sensor that uses a wired Ethernet connection or one with a self-contained cellular connection? As everything seems to be headed towards wireless these days, the knee-jerk response would be to buy the cellular sensor. It may be a good choice if conditions are ideal, but it's not always that simple.
So, here are a few things to consider before buying a cellular connected sensor:
Remote level sensors with a self-contained cellular connection rely on cell networks to function just like your cell phone. And as your recent bill for your smart phone might tell you; data can be expensive.
Some plans offer 1 MB per month for $10. To give you an idea, a single LOE ultrasonic sensor with a cellular modem works great with a 1 MB per month plan if you are calling in once every hour. This may not seem like much for a single sensor, but things can get expensive really quick when you need to monitor hundreds of tanks.
A medium sized business may have 500 tanks to monitor and a large company could have 5000 or more. That's a lot of monthly overhead. The only way to lower costs at this point is to have your sensors call in less often, which quickly erodes the quality of your remote monitoring program.
Even a small operation can incur large costs if they need their sensors to be more responsive - like calling in every 15 minutes or so.
On the other hand, data is relatively cheap when you have a hi-speed internet connection available. With all of that bandwidth, you can put hundreds of sensors online for less than $50 per month - no matter how often the sensor calls in and regardless of how much data is transmitted.
As I said before, cellular sensors are great for some applications when conditions are ideal. When these conditions are not ideal the sensor isn’t either.
For example, we recently had a customer approach us that had tanks installed where cellular networks were not available. Instead, they were using satellite communication. While they liked the cellular sensor they initially considered, it was useless at that particular location.
So they were introduced to our wired Ethernet solution, Tank Cloud. Since our sensors do not rely on a particular communication technology, they just needed some means to connect to the internet, whether it is landline, cellular, or satellite. In this case, satellite was the only option.
Some of our customers have multiple sites across the country. In some of these locations a landline is available. In locations that are remote, satellite may be the only available technology. So instead of using multiple vendors based on different communication technologies, they would rather use the same sensor for all sites. This way they have a one size fits all solution, and only the internet connection differs.
This simplifies the way that data is accessed and viewed and it streamlines the process of maintaining the sensor network through interchangeability. You don't have to train your employees on multiple platforms. You don't have to call multiple vendors when something needs to be replaced.
Southwest Airlines is thriving with a single plane model when American Airlines is in constant financial trouble. Why? Maybe they have too many different airplane and parts suppliers.
So before you make your decision between wired and wireless, do your due diligence and know what Internet connection options are available. If everything works with a cellular connection, then you can take advantage of the convenience of a built-in cellular connection, but at steeper data costs.
If you can bundle many sensors on the same landline Internet connection (such as at a tank farm), or if your remote sensors will need a few different Internet connection technologies, then you should go with a solution that works with any Internet connection.
If you have any questions on whether to use a wired or wireless remote level sensor, please contact us.
